CLYDE F. E. ROP

and WALTER L. BRUNDAGE, JR

Cirrate Octopods

with Associated

'Deep-Sea Organisms:

New Biological

Data Based on Deep

Benthic Photographs

(Cephalopoda)

SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY NUMBER 121
SERIAL PUBLICATIONS OF TH E SMITHSONIA N INSTITUTION

The emphasis upon publications as a means of diffusing knowledge was expressed

by the first Secretary of the Smithsonian Institution. In his formal plan for the Institution, Joseph Henry articulated a program that included the following statement:

"It is proposed to publish a series of reports, giving an account of the new discoveries

in science, and of the changes made from year to year in all branches of knowledge."

This keynote of basic research has been adhered to over the years in the issuance

of thousands of titles in serial publications under the Smithsonian imprint, commencing with Smithsonian Contributions to Knowledge in 1848 and continuing with

the following active series:

Smithsonian Annals of Flight

Smithsonian Contributions to Anthropology

Smithsonian Contributions to Astrophysics

Smithsonian Contributions to Botany

Smithsonian Contributions to the Earth Sciences

Smithsonian Contributions to Paleobiology

Smithsonian Contributions to Zoology

Smithsonian Studies in History and Technology

In these series, the Institution publishes original articles and monographs dealing

with the research and collections of its several museums and offices and of professional

colleagues at other institutions of learning. These papers report newly acquired facts,

synoptic interpretations of data, or original theory in specialized fields. These publications are distributed by mailing lists to libraries, laboratories, and other interested

institutions and specialists throughout the world. Individual copies may be obtained

from the Smithsonian Institution Press as long as stocks are available.

S. DILLON RIPLEY

Secretary

Smithsonian Institution

INTERNATIONAL WOK YEAR • 1*72
SMITHSONIAN CONTRIBUTIONS TO

ZOOLOGY

NUMBER 121

Clyde F. E. Roper GlTate OctOpods

and Walter L. Brundage, Jr. with AssOCiatPfl

Deep-Sea Organisms:

New Biological

Data Based on Deep

Benthic Photographs

(Cephalopoda)

SMITHSONIAN INSTITUTION PRESS

CITY OF WASHINGTON

1972
ABSTRACT

Roper, Clyde F. E., and Walter L. Brundage, Jr. Cirrate Octopods with Associated

Deep-Sea Organisms: New Biological Data Based on Deep Benthic Photographs

(Cephalopoda). Smithsonian Contributions to Zoology, number 121, 46 pages, 53

figures. 1972.—Twenty-seven photographs from seven deep-sea localities in the North

Atlantic reveal cirrate octopods in their natural habitat. The photographs demonstrate that these octopods are benthopelagic, living just above the bottom at depths

of 2,500 to greater than 5,000 m. Typical cephalopoda locomotion is exhibited as

well as a drifting or hunting phase, and possibly a pulsating phase. Animals range

in size from approximately 10 to 128 cm in total length, and up to 170 cm across

the outstretched arms and webs. Scale size was determined mainly by a new technique

termed shadow geometry, introduced here. Observations on shading ("coloration")

indicate the possibility of "reverse coloration" on some specimens. Cirrates are more

abundant in the Virgin Islands Basin than in other areas sampled. Additional photographs of plant debris, animals and lebensspuren (evidence of organisms in the sediment) suggest that the abundance level of benthic and benthopelagic organisms is

related to the presence of plant material of shallow-wat^r origin.

Library of Congress Cataloging in Publication Data

Roper, Clyde F. E., 1937-

Cirrate octopods with associated deep-sea organisms: New biological data based on deep

benthic photographs (Cephalopoda).

(Smithsonian contributions to zoology, no. 121)

Bibliography: p.

1. Octopoda. I. Brundage, Walter L., 1931- joint author. II- Title. III. Series: Smithsonian

Institution. Smithsonian contributions to zoology, no. 121.

QL1.S54 no. 121 [QL43O.2] 591.08s [594'.56] 72-476

Official publication date is handstamped in a limited number of initial copies and is recorded

in the Institution's annual report, Smithsonian Year.

For sale by the Superintendent of Documents, U.S. Gover nmen t Printing Office

Washington, D.C. 20402 - Price 65 cents (pap" cover)
Contents

Page

Introduction 1

Background of Study 1

Location of Photographs 2

Virgin Islands Basin 2

Other Localities 4

Acknowledgments 5

Techniques 5

Photography 5

Cameras 5

Lights and Control 6

Film and Processing 6

Photogrammetry 6

Known Altitude 6

Known Reference 6

Non-stereo Overlap 7

Shadow Geometry 7

Errors 7

Oceanographic Setting—Virgin Islands Basin 7

Bathymetry 7

Water Mass and Currents 7

Sediment 11

Systematics 11

Description of Photographed Octopods 12

Discussion 13

Biology of Cirrates 14

Habitat 14

Depth Distribution 16

Size 17

Locomotion 17

Water-ejection Style 19

Pulsating Style 23

Droguelike or Umbrella Style 24

Cirri 25

Coloration 26

Relative Abundance 31

Additional Cirrate Photographs 32

Observations 32

Photographs 33

Associated Organisms 33

Animals 33

Lebensspuren 39

Plant Detritus 40

Biomass 42

Literature Cited 44

Clyde F. E. Roper

and Walter L. Brundage, Jr.

Cirrate Octopods

with Associated

Deep-Sea Organisms:

New Biological

Data Based on Deep

Benthic Photographs

(Cephalopoda)

Introduction

BACKGROUND OF STUDY

Cirrate or finned octopods are among the rarest and

least known of all cephalopods. Not only are these

deep-sea animals relatively rare in collections, but

photographs of living specimens in their natural habitat have been nearly nonexistent. In November 1969,

during a 9-day search mission aboard the USNS

Mizar (T-AGOR-11), a total of at least twelve cirrate octopods was noted in a series of 20,000 exposures

made by the Naval Research Laboratory (NRL)

personnel. The purpose of the Navy mission was to

conduct a photographic survey north of the island

of St. Croix in the Virgin Islands Basin, Caribbean

Sea, at depths of 1,900 to 2,200 fm (3,480 to 4,020 m)

(Figures 1 and 2).

Clyde F. E. Roper, Division of Mollusks, National Museum

of Natural History, Smithsonian Institution, Washington,

D.C. 20560. Walter L. Brundage, Jr., Ocean Technology

Division, United States Naval Research Laboratory, Washington, D.C. 20390.

1

 Sea-floor photography has been practised by NRL for

purposes of search and inspection since the loss of the submarine Thresher in 1963. Approximately 10* photographs

have been taken during missions in the North Atlantic

Ocean and the Mediterranean and Caribbean Seas.

The cameras and other instruments which make up

a precision deep-sea search vehicle1 were towed from

the Mizar at speeds of between 1 and 2 knots and at

a nominal altitude above the bottom of about 5 m.

The value of large numbers of bottom photographs

from relatively small areas for assessing the environment and its inhabitants has been noted by Brundage

etal. (1967).

A search through photographic files at NRL and

several recent photographic cruises have produced

additional photographs of specimens from the North

Atlantic that now can be confirmed as cirrate octopods. Two of these photos, taken during the search

for the Thresher and at the time unidentified, were

published in Brundage et al. (1967, Figures, 6—19,

6-20). Two other finned octopods were photographed

in the Thresher search area and other photos came

from southwest of Bermuda, the Blake Basin and the

Canaries Basin. The photographs were taken in

depths that ranged from about 2,500 to 5,100 m. No

octopods have been noted in NRL collections of

photographs from shallower areas. Several additional

underwater photographs of cirrate octopods have

been brought to our attention by colleagues, some of

whom supplied copies for use in this report (e.g.,

Figures 8, 28, and 30-33). Figures 30-33 were taken

from the submersible Alvin at a depth of 1,300 m.

A lack of well-preserved specimens has led to a

1
SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

FIGURE 1.—Locations in the Atlantic Ocean of bottom photographs containing cirrate octopods

(Figures 7 through 33).

^—Virgin Islands Basin (VIB)

•—Bermuda (BDA)

O—Northeast Channel (NEC)

•—Canaries Basin (CAB)

D—Blake Basin (BLB)

A—Sohm Abyssal Plain (SAP)

X—Martha's Vineyard Slope (MVS)

present confusion in the literature concerning both

the systematics and the biology of cirrate octopods.

The unusual set of photographs presented here provides new information on the following aspects of

the biology of these animals: habitat, depth distribution, locomotion, "coloration," size, and relative

abundance.

In addition, a technique is discussed for calculating size and distance off the bottom of objects in

deep-sea photographs.

LOCATION OF PHOTOGRAPHS

Virgin Islands Basin.—The majority of our photographs were taken in a small area at the bottom of the

Virgin Islands Basin (VIB) in the vicinity of

17°52'N, 64°48'W (Figure 1).

The tracks of the towed camera vehicle ("fish") are

indicated by fine lines in Figure 2. The hachures indicate areas of concentrated track coverage. Locations

of the photographs of cirrate octopods are shown by

numbers which correspond to figure numbers 7, 9,

14-20, 22, 23, 25-27. The numbers 34 and 35 locate

two photographs of fish with corresponding figure

numbers. A count was made of selected animals along

a track located within the southwestern hachured area

(see page 39). Figures 36 through 50, 52 and 53 were

taken in that same area.
NUMBER 12 1

2 \

FIGURE 2.—Locations of bottom photographs in the Virgin Islands Basin. Thin lines indicate

tracks of towed instrument vehicle which yielded almost continuous photographic coverage.

Hachured areas represent dense concentration of tracks. Numbered symbols (except numbers

34 and 35) locate octopod photographs figured in this paper. Figures 36 through 50, 52 and

53 are confined to southwestern hachured area. Isobaths in fathoms (thick lines) developed

from acoustic tracking data (see text). Thick dashed lines locate sections of seismic profile

(see Figure 6). Inset chart adapted from Frasetto and Northrup (1957:139).

Mizar's surface navigation was obtained through a

radio voice linked between the ship and two theodolite

stations on St. Croix (see Figure 2, insert map).

The location of the cameras relative to Mizar was obtained by an underwater acoustic tracking system

(Andrews, 1965). The overall accuracy of location of

the photographs is estimated to be ± 80 m. The isobaths were developed from the same data using a

harmonic mean sound speed of 4,950 ft/sec (1,509

m/sec).

A triangular array of three hydrophones mounted

on Mizar's hull and a responder installed on the fish

were the essential acoustic components of the tracking system used on this cruise (Figure 3). The computer-controlled system began a cycle when an electrical signal was transmitted down the coaxial towing
SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

OCEAN SURFACE

TRACKING HYDROPHONES

TOWED

INSTRUMENT

VEHICLE

OCEAN BOTTOM

FIGURE 3.—Diagram of acoustic navigation system used to measure depth and to locate photograph with respect to ship which navigated precisely from theodolite stations on St. Croix

(see Figure 2, inset). Electrical signal sent down coaxial towing cable initiates acoustic reply

(upward expanding arcs) from responder on camera-equipped vehicle. Time of the interrogation (outgoing) signal and arrival times of reply at tracking hydrophones are processed by

computer along with roll, pitch, and heading data to give location of towed vehicle in three

dimensions.

cable to the responder on the camera vehicle. The

automatic acoustic reply from the responder was received by the three hydrophones. Interrogation time

and the times of receipt of the replies were processed

by the computer, taking into account roll, pitch, and

heading of the ship. This resulted in a print-out of the

camera's N/S, E/W and vertical coordinates relative

to the ship.

Other localities.—Other photographs come from

scattered areas in the North Atlantic. A number of

cirrates were photographed in the Blake Basin (BLB)

at about 29°20'N, 76°W. A single photograph was

taken southeast of Bermuda (BDA) at 31°43/N,

64°48'W. Four photographs of cirrates were taken

in the vicinity of Northeast Channel (NEC) at the

base of the continental slope off New England at

41°45'N, 65 °W, one was taken in the Canaries Basin

(CAB) at about 33°N, 33°W, another was photographed on the Sohm Abyssal Plain (SAP) at

32°42'N, 57°H'W and four exposures (one specimen) were obtained from the submersible Alvin on

the continental slope south of Martha's Vineyard
NUMBE R 12 1

(MVS) at 39°46'N, 70°32'W. These locations and

the Virgin Islands Basin locality are shown by different symbols on the chart of the North Atlantic

(Figure 1).

ACKNOWLEDGMENTS

We express our gratitude to a number of people who

have helped measurably during the preparation of this

report: C. L. Buchanan, NRL, for the opportunity

to study and publish the majority of the photographs;

V. J. Linnenbom, NRL, for two of the Blake Basin

photographs (Figures 12 and 13); J. Lamar Worzel, Lamont-Doherty Geological Observatory, for the

Figure 8 photograph; R. Bridge, J. J. Gennari,

D. Clamons, F. Heemstra and H. Barnes, NRL, for

aiding in the preparation of the navigation, bathymetric and scale data; G. L. Voss, Institute of Marine

Sciences, Miami, for providing records of Cirrothauma murrayi and for attempting to trawl specimens in

the Virgin Islands Basin; E. S. McSweeny, IMS, for

supplying data and checking specimens; R. E. Young,

Department of Oceanography, University of Hawaii

for valuable suggestions concerning cirrate systematics and biology; D. Cohen, Systematics Biology

Laboratory, Bureau of Commercial Fisheries, for

discussions about the benthopelagic habitat and fauna

and for identifying some fishes; N. B. Marshall,

British Museum (Natural History) ; R. H. Gibbs, Jr.,

Smithsonian Institution; J. Nielson, Zoological Museum, Copenhagen, and E. Bertelsen, Denmark

Fisheries, for identifying fishes and for discussions

about deep-sea organisms; D. Stanley, Smithsonian

Institution, and H. Ladd, United States Geological

Survey, for information concerning the sediments;

T. Bowman, Smithsonian Institution, for data concerning the habitats of certain deep-sea crustaceans;

H. J. Humm, University of South Florida, for confirming the identity of the sea grasses and for the

suggestion concerning Laurencia; G. Mead, Los Angeles County Museum of Natural History, for identifying the bathysaurid fish; J. Allen, Dove Marine Laboratory for comments on mollusk identities; H. L.

Sanders, Woods Hole Oceanographic Institution, for

information about the deep-living sea urchin Echinus

in the Western Atlantic; and J. R. Brown, Naval Air

Development Center, for the unpublished data on

the movements of deeply moored buoy systems in

the Virgin Islands Basin.

Additional photographs taken from the submersible

Alvin, along with observations on the specimen, were

kindly supplied by R. R. Hessler, Scripps Institution

of Oceanography. We acknowledge B. C. Heezen,

Lamont-Doherty Geological Observatory, C. D.

Hollister, Woods Hole Oceanographic Institution, and

Oxford Press for permission to publish a photograph

from their book (our Figure 28).

Comments on the identity of organisms shown

in the photographs were made by colleagues in the

Department of Invertebrate Zoology, Smithsonian Institution: I. Canet, F. Chace, M. Jones, R. Manning,

D. Pawson, J. Rosewater and K. Ruetzler.

R. Gatton and M. Sweeney, Smithsonian Institution, prepared Figure 1 and provided technical assistance. R. Sibley and G. Baker of the Naval Reconnaissance and Technical Support Center assisted

with the preparation of some photographs.

All or parts of the manuscript were read by C. L.

Buchanan, R. H. Gibbs, Jr., J. B. Hersey, C. C. Lu,

R. J. Menzies, J. Nielsen, W. Pearcy, R. Swim,

G. L. Voss and R. E. Young. Their comments and

criticisms were especially appreciated. The manuscript was edited and typed by Mrs. V. Macintyre

to whom we express our thanks.

This study was supported in part under NRL problem number 84-G01-03.

Techniques

PHOTOGRAPHY

Cameras.—All of the NRL photographs in our

study were taken with EG&G (Edgerton, Germeshausen and Grier) 35-mm cameras using the Hopkins

water-corrected f 4.5 lens (Hopkins and Edgerton,

1961) or modified to accept a Kinoptic® wide-angle

(WA) lens behind a hemispherical view port (Patterson, 1967)2

. The normal angle (NA) Hopkins

lens covers an underwater field of approximately 34°

by 48° compared with the WA lens which has an effective coverage of about 106° in a circular image.

Lens apertures generally were set at f 4.5 on the NA

and f 4 on the WA cameras. With the exception of

Figures 10, 11, 13 and 18, which are oblique photographs, all exposures were made with vertically oriented cameras. Other obliques supplied by col1

 Use of trade names does not imply product endorsement.
SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

leagues were Figures 8 and 28 taken with the Thorndike camera (Thorndike, 1959), and Figures 30-33

taken with standard EG&G cameras mounted on the

submersible Alvin.

The WA camera does not have the resolving power of the NA camera but serves well in its capacity

as a search tool. Fortunately, most of our photographs

of Virgin Islands Basin cirrates were taken with NA

cameras. Data frames are photographed simultaneously with each bottom image; one type of EG&G

camera (model 207A) projects the data image of

clock, frame count and written information directly

through a portion of the photograph, resulting in occasional interference (e.g., Figure 7).

Lights and control.—Light for the photographs

was supplied by two EG&G 250 watt-second electronic flash lamps located side by side at the trailing

end of the "fish." Remotely operated, deep-sea cameras normally function with open shutters, permitting

the short duration (approx. 1 millisecond) flash to

take the picture.

During the Virgin Islands Basin cruise the interval

between photographs usually was 10 seconds for the

NA camera and 30 seconds for the WA camera, a

procedure which required a shutter on the WA camera. Separate control for the cameras was provided

by signals telemetered (Buchanan and Isaacson,

1968) down the insulated core and coaxial shield of

the towing cable.

Height (altitude) of the camera off the bottom

was monitored with a 12 kHz acoustic pinger. The

sonar signals were received at a hull hydrophone and

displayed alongside remote winch controls on a precision depth recorder (PDR). Electrical analogs of

the same signals were telemetered directly up the

cable and displayed on a nearby oscilloscope. Undesirable altitude changes, therefore, could be rectified

immediately. Extra long "pings" were registered on

the PDR at the time each exposure was taken. Timing

of all signals was controlled by a digital clock

aboard Mizar.

Film and processing.—All cameras were loaded

with black and white 35 mm Kodak Linagraph shellburst film which has a "qualified" ASA rating of

400. Development was carried out aboard Mizar

using a two-bath developer (Diafine®) that tends to

enhance image details near the edges of photographs

were illumination is normally reduced (see Brundage

and Patterson, 1966, Fig. 13).

PHOTOGRAMMETRY

Accurate scale is easily determined with a matched

pair of (stereo) cameras aligned to form an overlapping field of view (Boyce, 1964; Pollio, 1969).

Priorities established for the NKL-Mizar search camera system have rarely permitted the use of stereo;

therefore other methods of measuring scale had to be

worked out. The photograph in Figure 21 is one of

a stereo pair, the only one presented in this study.

The methods used to determine the 30-cm scale mark

shown in the other photographs (Figures 7—53, except 28 and 30-33) are discussed below. The mark is

shown at the midwater level of the octopods in photographs preceding Figure 30 and as a bottom scale in

Figures 36-53. Because of a lack of information,

scale could not be calculated for Figures 9, 14, 15, 18,

and 31-35.

Known altitude.—Estimates of bottom scale in

single photographs are usually based upon knowledge of the angle of view of the camera and altitude

above the sea floor. Angle of view for a lens behind

a flat port can be calculated from the simple relationship:

tan x-0.5b f—» n- 1

where x is one-half the view angle, b is the image size

on the film plane, f is the calibrated focal length of the

lens in air and n is the index of refraction of the

water.3 Altitude is more difficult to establish and

usually entails correlation with simultaneously recorded acoustic data. Record matching is eased if the

"blank ping" method of Hersey (1967:61) or some

other system (see above) is used to mark the

time of exposure directly on the acoustic record.

Difficulties in reading the record often result in scale

measurement errors of up to plus or minus 20% at

the altitudes usually "flown." This method was applied for Figure 51.

Known reference.—An accurate but usually fortuitous method of measuring scale makes use of an object of known size in the field of view. For example

when a 34-cm-long EG&G model 260 compass is

suspended from the camera vehicle it frequently

strikes the bottom at the moment an exposure is

made, thereby allowing establishment of scale. Such

a compass appears in many photographs presented

*The typical index for sea water of 1.34 is accurate

enough for these methods.
NUMBER 12 1

here and it was used to measure the scale in Figure

24. In Figure 12 the swimming octopod was scaled

from the known sizes of the compass and magnetometer to either side of its position. White sea

urchins4, so common in the Thresher search area,

were measured on or near objects of known size and

provided a secondary comparative scale (see Brundage et al., 1967: 77-78) because the population had

a very narrow size distribution. This method was

applied in Figures 8 and 11.

Non-stereo overlap.—Simultaneous photographs

taken by non-stereo cameras can be used to accurately measure scale when the optic axes of the

cameras are parallel. Displacement of the same object measured from the centers of each photograph

is plotted as the known separation between the

cameras. The method works best if the plane of reference is normal to the optic axes. This technique

was applied in Figures 13, 25, 26 and 29.

Shadow geometry.—Relatively accurate scale in a

single photograph can be determined from the position of a shadow cast by an object suspended in the

field of view. Care must be taken to measure the

light-to-camera distance and to place the suspended

object so that its image will appear near the side of the

photograph toward the light. In the typical arrangement shown in Figure 4, a 34-cm-long EG&G model

260 compass is suspended about 3 m beneath the

vehicle/' Light from a pair of flash lamps casts a

double shadow (image) easy to distinguish at high

altitudes. The distance between images of shadows

and compass (H on Figure 4) becomes a measure of

altitude and hence of bottom scale. Figure 5 illustrates

a determination of scale by shadow geometry in

which the size of an octopocl in midwater is determined using an extension of the method. Details of

the method are beyond the scope of this work and

are reported elsewhere (Brundage, in press). Scale in

Figures 7, 16, 17, 19, 20, 22, 23, 27, and 36 through

53 was determined by shadow geometry. The scale

in Figure 10, an oblique photograph, was determined

by a complex combination of the above and other

methods.

Errors.—No systematic treatment of errors can

' These all appear to be members of a single species of

Echinus (Howard L. Sanders, pers. comm.).

11

 Distance below the vehicle should be about one-half

the expected altitude.

be made for the above photogrammeteric methods

short of duplicating the measurements over a known

bottom grid. The fpllowing estimate of errors is

based on experience gained while applying and comparing the methods and by taking the occasional opportunity to measure an object of known size (e.g.,

the vaned compass) on the bottom:

± 10% known reference

±15 % known secondary reference (e.g. "urchin

scale")

± 3 % non-stereo overlap

± 5 % shadow geometry

These should be regarded as maximum estimates of

error.

Oceanographic Setting—Virgin Islands Basin

BATHYMETRY

All camera runs were made near the base of a steep

escarpment that was contoured by Frasetto and

Northrup (1957). These isobaths are in good agreement with those constructed from the NRL data

(Figure 2 and inset) but the photographs indicate

that the area is more complex than is shown by either

study. Many small erosion channels, ledges and rock

outcrops were photographed especially in the central and eastern sections. This study area borders on

the flat floor that begins with the 2,300-fm (4,210-m)

contour. The basin is completely encompassed by

sills that rise more than 1,200 fin (2,200 m) above

the floor.

A recent seismic reflection study (Perry and Massingill, 1971) revealed a small ridgelike feature which

parallels our contours and behind which the seismic

reflection surfaces look somewhat disturbed (Figure

6). The location of the crest of the ridge coincides

approximately with our longest continuous 2,200-fm

(4,020-m) isobath. The companion troughlike feature has a relatively flat floor and is located between

the ridge and the 2,100-fm (3,840-m) contour (see

Figure 2).

WATER MASS AND CURRENTS

Below sill depth the basin water has nearly uniform

physical parameters characterized by temperatures

between 3.7° and 3.9°C and a salinity between 34.96

and 34.98%, (Wiist, 1964). Westerly currents domi-
SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

CAMERA J LIGHTS

PROJECTED

COMPASS

IMAGE

FIGURE 4.—Spatial relationship of camera system components essential for measurement of

bottom scale using "shadow geometry." Electronic flash lamps located at trailing edge of

vehicle cast double shadow of suspended compass. "Area photographed" represents the hypothetical maximum coverage in a single photograph of a flat bottom when camera is vertical.

Distance between image of compass head and its shadow (H), measured on a line parallel to

the camera-lights axis, changes linearly with altitude of camera above sea floor. Details in

Figure 5 and text.
NUMBE R 12 1

Instrument vatticl*

outlin*

GRAPHIC SOLUTION

OF

SCALE PROBLEM

FIGURE 5.—Scale determination by "shadow geometry." The octopod photograph (left) is

marked with reference points X and Y for measurement of camera altitude and with points

A, B, C, D and E for determination of the midwater location and scale of the animal. The

simplified graphic solution to the problem (right) shows the most important relationships.

Angle FOG is camera angle of view in the camera-light plane. Location of compass on camera

arc permits a rough correction for vehicle pitch. For a detailed explanation of the method see

Brundage, in press.

nate the surface waters but a section of potential

temperature (Wiist, 1964, Plate L) through the Virgin Islands Basin exhibits isotherms bending upwards toward the perimeter indicating a possible

rotary circulation pattern below sill level. While it

can be argued that such non-synoptic data are often

misleading, the data from three other stations

(Worthington, 1966:737-738) taken over a period

of about two days disclosed a similar upward bending of potential temperature isotherms. Direct measurements of deep currents are lacking in this region.

However, Naval Air Development Center personnel

experienced what appeared to be a northeasterly current at depth in the southeast corner of the basin for

several days following the November 1968 deployment of deep-moored experimental buoy systems

(J. R. Brown, per. roinm.), some of which were

sunk and later photographed during the NRL survey.

A northeasterly current in that corner of the basin

fits a pattern of cyclonic circulation.6

* Two sets of observations are pertinent regarding the

buoy systems which failed to anchor themselves (see Hal-
10 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

5 0 0

1000

1500

LETTERS LOCATE

MAJOR COURSE

CHANGES AND

ENDS OF TRACK

(SEE FIGURE 2)

2000

FIGURE 6.—Reconstruction of seismic profile (after Perry and Massingill, 1971). Area of interest is around sharp ridge and gentle depression. Ridge apparently acts as a dam, impounding

large quantities of organic debris. A 2,150-fm (3,931-m) isobath (not plotted on our figure)

between 2,100 fm (3,840 m) and 2,200 fm (4,023 m) outlines several closed depressions.

Depths corrected for sounding speed of 4,950 ft/sec (1,509 m/sec).

Although we seem to have given undue attention

to probable deep currents we show later that a

reversal of flow at depth could play a role in the concentration of organic detritus in the area where the

octopods were photographed.

Near-bottom current evidence in the form of ripple

marks was lacking in thousands of bottom photographs studied even though there was an abundance

of particles in the medium to coarse sand-size range

(0.25 to 1.0 mm), the size most easily transported

berg and Meyers, 1966, for description of similar buoy

system) : (a) surface floats with mooring cables which

parted at lengths shorter than 2,000 m moved immediately

westward at close to the half-knot speed of the surface

current and, (b) surface floats with cables which broke

near the bottom (ca. 4,000 m) appeared at first to be

firmly anchored. However, after several days of careful

position checks they were observed to have been moving

towards the north-northeast at a rate of approximately

1.1 km/day.

Atlantic water cascading periodically into the eastern end

of the basin through the Anegada Passage might supply the

impelling force for a gyral much as the cold water flowing

over the sill between Iceland and Greenland imparts cyclonic

angular momentum to the bottom water of the basins to the

south (Bjerkness, 1960).
NUMBE R 12 1

(Inman, 1963:126). The filling of numerous animal

trails and depressions in the bottom by light-colored

surface sediment indicates however that either sporadic bottom currents of variable direction do occur

or that the movement is caused by the stirring action

of the relatively numerous bottom and near-bottom

animals.

SEDIMENT

A grab sample was recovered from the western edge

of the study area at 17°51.2'N, 64°49.5'W in 2,130

fm (3,895 m) of water. The primarily calcareous

sediment consists of material of shallow-water origin

(from the reef front platform and possibly from the

margin) and of pelagic origin (D. Stanley, pers.

comm.). The results of a size analysis on this sample

are presented in Table 1 along with a commentary

on the composition of the particles within each size

fraction. Shallow-water influence is evidenced especially by constituents of the coarser sand and fine

gravel sizes which include a whole polyp of a solitary

scleractinian coral. Photographs of whole shallowwater gastropod shells, a brain coral head, mangrove leaves and sea grass fragments are additional

evidence of shallow-water materials.

Although the grab sample contained very little

material finer than sand ( < .062 mm) other evidence indicates that clay and silt-sized sediment occurs in the area. One sample of opportunity was

packed into the cup-shaped hollow fitting on the end

11

of one of the cylindrical arms which jut out from the

grab sampler. The innermost unwashed portion of

this sediment was composed of a light-tan-colored,

sticky calcareous clay. Photographs show that the

clay was picked up when the sampler plunged sideways into the bank of an erosion channel about

20 cm below the rim. Evidence of other fine sediment

on the bottom comes from many photographs of

clouds of silt stirred up by the vaned compass which

was suspended beneath the camera vehicle.

Systematics

Knowledge about the systematics of the finned octopods (suborder Cirrata) is fragmentary, and an understanding of the relationships of the numerous nominal entities, even at the familial level, is lacking. This

is a result of several related factors. (1) Relatively

few specimens exist in research collections. (2) The

animals are semigelatinous and fragile; therefore few

complete, undamaged specimens exist. Material generally comes out of collecting nets damaged, undergoes shrinkage and distortion during fixation and

preservation, and continues to deteriorate during

storage. (3) Few reliable taxonomic characters have

been delineated in this group. (4) No modern systematic treatment of the cirrates has been undertaken.

The most comprehensive information on the cirrate octopods is found in Robson's monograph

(1932). Robson compiled all known records and

TABLE I.—Sediment Size Analysis and Description

Size (mm)

>2

1 to 2

0.5 to 1

0.25 to 0.5

0.125 to 0.25

0.062 to 0.125

<0.062

Percent by

Volume

11

12

29

24

10

5

9

Composition

Coral, pelecypod, gastropod, sea urchin and bryozoan fragments from shallow water and chips

of dark volcanic rock with pelagic pteropod and heteropod shells. (Fine calcareous granules.)

Pteropods and foraminifera shells with fragments of pelecypod and gastropod shells plus 3%

volcanic and other terrigenous lithic fragments.

Coarse foraminiferal sand mainly of planktonic origin with lithic constituents which include

black shale-slate.

Medium pelagic foraminiferal sand (75-80% globigerina), shells and fragments of forams and

pteropods—terrigenous fragments present but rare.

Fine fragmented foraminiferal sand and shells with fragments of sponge spicules—rock fragments increase to about 10%.

Very fine fragmented foraminiferal sand (3-5% whole tests)—terrigenous fragments present

but rare.

Not examined.
12 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

species and attempted to characterize species and

delineate the systematics of the group. In spite of this

effort, with few exceptions, e.g. Cirrothauma murrayi

and Opisthoteuthis species, identification of finned

octopods remains a difficult if not impossible task. At

the present time the suborder Cirrata is comprised of

about 8 nominal genera and nearly 30 nominal species

distributed in the families Cirroteuthidae, Stauroteuthidae and Opisthoteuthidae.

DESCRIPTION OF PHOTOGRAPHED OCTOPODS

The description is based on an analysis of most of

the photographs through Figure 29. A figure reference

is given for each described character. We recognize

the possibility that more than one species may be represented in the series of photographs.

The mantle, or body, is a relatively long, bluntly

rounded, cylindrical sac (e.g. Figures 7, 8, 9, 11, 13).

The head is well defined and is the widest part of the

body as a result of the large somewhat bulging eyes

(Figures 7-9).

The fins are long and broad; each is as long (axis

perpendicular to the body) as or longer than the

width of the mantle (Figures 9, 11, 20, 22, 25). The

posterior borders of the fins are attached at or slightly

anterior to the midpoint of the mantle, so that the

fins extend anteriorly nearly to the posterior border

of the eye openings (Figures 7-9). The posterior

borders arise perpendicular to the body axis and reTABLE II.—Data for Photographs of Cirrate Octopods

Specimen

Figure No.

Area • Location Date

North West

Bottom AltiDepth tudeb

(meters) (meters)

7 ....

8

9

10

11

12 ...

13

14-15

16

17 ...

18

19

20

21

22

23

24

25-26

27 ....

28

29

30-33

VIB

NEC

VIB

BDA

NEC

BLB

BLB

VIB

VIB

VIB

VIB

VIB

VIB

BLB

VIB

VIB

CAB

VIB

VIB

SAP

BLB

MVS

17°50.8'

41°45'

17°50.8'

31°43'

41°44'

29°23'

29°23'

17°51.8'

17°51.6'

17°51.2'

17°51.0'

17°51.6'

17°52.6'

29°22'

17°51.9'

17°51.0'

33°

17°51.0'

17°51.2'

32°42'

29°22'

39°46'

64°47.8'

64°56'

64°48.5'

64° 48'

65°56'

75°58'

75°58'

64° 48.4'

64°47.1'

64°48.2'

64° 49.4'

64°47.1'

64°46.9'

75°58'

64°46.6'

64°48.5'

33°

64°48.6'

64°48.3'

57°11'

75° 58'

70°32'

20.XI.69

15.VI.63

21.XI.69

19.IV.65

10.IX.64

12.X.7O

14.X.70

25.XI.69

19.XI.69

27.XI.69

21.XI.69

19.XI.69

20.XI.69

19.VI.71

20.XI.69

26.XI.69

28.VIII.68

26.XI.69

27.XI.69

16.11.67

19.VI.71

26.IX.67

3480 c

2500

3620

4250

2500

5030

5030

3990

3660

3770

3790

3620

3970

5110

3770

3710

3500

3730

3770

5202

5110

1300

1.1

1.1

1.7

0.5

1

1.8

1

0.5

0.8

0.5

0.5

• Areas are located on chart (Figure I) by the following abbreviations:

VIB — (Virgin Islands Basin)

BDA — (Bermuda)

NEC — (Northeast Channel)

CAB — (Canaries Basin)

BLB — (Blake Basin)

SAP — (Sohm Abyssal Plain)

MVS— (Martha's Vineyard Slope)

b

 Altitude = average altitude of specimen above bottom.

c

 VIB depths corrected to nearest 10m.
NUMBER 12 1 13

main straight or slightly convex nearly to the bluntly

rounded anterior angle (Figures 9, 25). The anterior

borders are lobed or convex so that a small notch is

formed at the anterior basal attachment (Figure 25).

The arms are long and comprise about 2/3 the

total length of the animal (Figures 8, 9, 11, 14). Arm

pairs I and II appear to be the longest (Figures 7—9).

The arms are drawn out into fine, attenuate tips

(Figures 8, 9, 20, 22). Long cirri are present along at

least the distal i/3 to i/2 of the arms (Figure 20). All

the arms are connected by a thin, membranous interbrachial web (Figures 20-22, 25, 27) that is attached

to the dorsal (aboral) surface of each arm by an intermediate or secondary web (Figures 20—22). The interbrachial web reaches nearly to the tips of the arms

when fully expanded (Figure 22).

DISCUSSION

Many of the characters that have been used in classifying the cirrates are internal features. The primary

character for distinguishing genera (or families) is

the configuration of the cartilaginous shell-vestige or

fin support that is embedded in the posterodorsal

part of the mantle (body) and serves as a base for

the attachment of the fins. The support can be "saddle shaped," with or without limbs, U- or V-shaped.

Other internal characters include the presence or absence of the median adductor muscle, the presence

or absence of a crop, the size of the gills and the arrangement of gill filaments.

External characters that have been utilized in the

past are, chiefly, the presence or absence of a secondary or intermediate web between the primary interbrachial web and the arms, the extent of the mantle opening, relative proportions (and shapes) of the

body, fins, head and arms, and configuration of suckers

and cirri.

In attempting to identify the specimens in the

photographs presented here it is possible to eliminate

some of the more distinctive cirrates solely on the

basis of external characters. Members of the monotypic family Opisthoteuthidae are eliminated because of

their flattened or belllike shape characterized by the

absence of a well-developed body posterior to the

head, as well as small, short fins. Comparison of our

photos with the illustrations in Berry (1952, Figure

1) and especially with living specimens of Opisthoteuthis californiana shown in Pereyra (1965, Figure 3)

emphasizes these differences.

Grimpoteuthis (Stauroteuthidae) also has a short

body (although it is not as flattened as in Opisthoteuthis), relatively short fins—shorter than the width

of the head, and no intermediate web. Fin size may be

too variable to be a dependable character in this

genus, but the short body and the absence of an intermediate web in Grimpoteuthis appear to preclude a

close relationship with the photographed specimens.

Although Cirrothauma murrayi (Cirroteuthidae)

is known only from the original specimen, a second

specimen noted by Voss (1967) and Mohr and Geiger

(1968), and three additional specimens reported in

this paper (courtesy of G. L. Voss, pers. comm.), it is

readily distinguished from other known cirrates by its

extremely reduced eyes that are embedded in and

covered over by gelatinous tissue (Chun, 1914, Figures 7, 9; 1915, Pis. 92, 93). Three of our specimens

show distinct eyes and large eye openings (Figures

7—9) which are sufficient to preclude their identity

with Cirrothauma.

So little is known of most of the remaining genera,

e.g. Stauroteuthis Verrill, 1879, Frokenia Hoyle,

1904, and Chunioteuthis Grimpe, 1916, that comparison is fruitless. In fact, future systematic studies may

well show that considerable generic overnaming has

occurred in the Cirrata.

Cirroteuthis muelleri Eschricht, 1838, was the first

citrate octopod to be described, and it has been reported from the North Atlantic on several occasions

(see Robson, 1932). Cirroteuthis possesses an elongate body, a "prominent" head, a secondary or intermediate web, a moderately narrow mantle aperture,

large, broad fins set closer to the eyes than to the apex

of the body (or at least at the midpoint between eye

and apex in some specimens), and arms about y$ the

total length of the animal.

Reinhardt and Prosch (1846) published an account of Cirroteuthis muelleri and included good illustrations. Some of the specimens in our photographs

(e.g., Figures 9, 25) very closely resemble their illustrations.

On the basis of the current status of systematics in

cirromorph octopods, it is impossible to definitely

place the specimens in our photographs in one of

these genera. However, the general features of these

octopods are in many ways similar to those of Cirroteuthis and we tentatively assign our animals to this

genus.
14 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

The following table lists the described characteristics of Cirroteuthis that are also visible in our photographs:

Character

Elongate body

Prominent head

Intermediate web

Long fins

Anteriorly placed fins

Long arms

Prominent eyes

Figures

7-11, 13, 27

7-9

16, 20, 22

9-11, 20, 22, 25, 27

7-10

8-10, 13, 20, 22, 25, 27

7-9

Whether the photographed specimens are indeed

Cirroteuthis must await a systematic revision of the

suborder as well as the capture of specimens so that

internal as well as external characters can be studied.

Biology of Cirrates

HABITAT

Considerable discussion appears in the literature concerning the habitat of cirrate octopods (see reviews in

Robson, 1932; Voss, 1967). It is now fairly well established that Opisthoteuthis is a benthic form, first

on the basis of morphological interpretation, and

more recently through the more direct observations of

Pereyra (1965). All except one of Pereyra's specimens of O. californiana were taken in bottom-fishing

trawls; the exception was captured in a net set to fish

6 meters above the bottom. As Pereyra described the

swimming capability of O. calijorniana, occasional

off-bottom excursions and captures may be expected.

Chun (1914:16, 21) described Cirrothauma murrayi from a single specimen taken at Michael Sars

Station 82 with a pelagic trawl with 3,000 meters of

wire out (Murray and Hjort, 1912:xix). The bottom

depth in that locality (48°24'N, 36°53'W) generally exceeds 4,000 m, so clearly the net almost certainly was not on or near the bottom. A series of seamounts occurs about 2° eastward of the recorded

locality along the 35° meridian between 38° and 40°

N Latitude so that the possibility that the net fished

over an uncharted seamount—therefore closer to the

bottom—cannot be completely ruled out. Bruun

(1943:15) suggested that fishing depths for pelagic

trawls used on the Dana Expeditions could be estimated as one-half the amount of wire out for tows

with greater than 1,000 m of wire out and one-third

the amount for shallower tows. Most pelagic trawls

do not achieve so low an angle, so that in the absence

of wire angle or other data from the Michael Sars,

we may take one-half as the maximum estimate.

Chun's specimen, therefore, probably was captured

in less than 1,500 m, and he stated (p. 21) that the

species is pelagic. Robson (1932:84) mistakenly

listed the depth of capture as 3,000 m (1,641 fms).

Additional specimens of Cirrothauma are in the

collections of the Institute of Marine Sciences, Miami

(Voss, 1967; and pers. comm.). The records of capture are tabulated here as a further indication of

depth range, habitat and geographic distribution of

the species:

40

57

55

86

Location

°46'S

°39'S

°25'S

°N

76°

52°

78°

173

48'W

02'W

28'W

°E

Sampling Depth

(meters)

2893

3980-4136

3440-3705

0

Bottom Depth

(meters)

3700

4013-4136

4337

-

Gear

3m IKMT

10'Blake

3m IKMT

dipnet

Vessel-Station

Eltanin-175

Eltanin-\b\A

Eltanin-878

Arliss II

(Ice Island)

The Eltanin specimens come from off southern

Chile, in the Drake Passage, and in the Scotia Sea;

two were caught in midwater trawls at least 630

meters above the bottom. The third specimen was

captured in a Blake trawl that was set to fish on the

bottom at over 4,000 m. Whether the specimen was

captured on the bottom or in midwater during the

long period required for set and retrieval, which

seems more likely, cannot be known. The specimen

from the Arctic Ocean was dipped at the surface

from a hole in the ice on drift station Arliss II. The

specimen was noted to be "alive" at the time of capture (Ronald McPeak, University of Southern California, collector). These records verify the pelagic

habitat and broad geographic range of the genus. The

surface capture of the Arctic specimen certainly contradicts the otherwise very deep records. This may,

however, be an example of polar emergence.

Knowledge about the habitat of remaining cirrates,

however, is contradictory. Robson (1932:19) believed that it was safe to infer a benthic habitat for a

deep-water member of a group if its shallow-water
NUMBER 1 2 1 15

relatives were benthic dwellers. This type of inference,

whether valid or not, is not applicable to the cirrates

since no shallow-water representatives are known.

(Opisthoteuthis, the shallowest living cirrate genus,

has been recorded as shallow as 125 m [Pereyra,

1965:429] and as deep as 2,251 m [Verrill, 1885:

446] with the great majority in excess of 400 m; it can

hardly be considered shallow living.) Robson (1932),

after considerable discussion, was inclined to assign

a benthic or near-bottom habitat for the cirrates,

while Voss (1967:522) considered them abyssopelagic organisms (except Opisthoteuthis). Dollo

(1912) and Abel (1916) attempted to determine the

habitat of some cirrates on the basis of structure.

Dollo (p. 129) thought that Cirroteuthis muelleri

was nektonic because of its fins. Abel (pp. 18, 55,

72, 105) regarded C. muelleri and several other Cirroteuthis-\\Ve species as nektonic or planktonic because of the fins (as balance structures) and webs.

He considered other species benthic because they had

depressed bodies and dorsal eyes, or because they

resembled Sepiola, a sepioid squid. The last reason,

especially, is untenable. Abel (p. 55) also believed

that Cirrothauma murrayi was a benthic form that

burrows in the mud (hence, the atrophied eyes). In

his attempt to derive function and habitat from morphological considerations alone, Abel led himself

astray, since the only recorded specimen of this species was captured at a maximum estimated depth of

1,500 m in a water depth of over 4,000 m.

Chun (1914:16, 20) considered that Grimpoteuthis umbellata was a bottom dweller because it was

captured only in bottom trawls.

Inference of habitat on the basis of type of gear

which captured cirrates was inconclusive. Although

most captures have been made in non-closing benthic

trawls, this could not preclude the possibility of capture in midwater while the net was being retrieved.

Personal observations (G. F. E. Roper and R. E.

Young) as a result of occasional captures in the

Antarctic Ocean in 1963-1964 of cirrates in deepfishing midwater trawls that approached the bottom

led to the conjecture that some cirrates must be

benthopelagic organisms that spend their lives in association with, but not restricted to, the bottom.

Stomach contents from a Grimpoteuthis species

from 2,425 fms (4,438 m) included remains of 9

species of benthic crustaceans (Scott, 1910:52) and

Robson (1930:378) reported fragments of polychaetes from the stomach of G. glacialis; presumably

these food items were captured on or near the bottom. The isopods, amphipods, and one of the copepod species identified by Scott are known to be deepliving benthic form*. Single specimens of species of

copepods, known to be shallower living pelagic species, may represent contamination (e.g. in the mantle

cavity), secondary ingestion, or misidentification

(since the specimens were minute and in poor condition) (T. Bowman, pers. comm.).

All of the photographs presented here, plus several

others in our files, show the octopods above the bottom. All but three specimens are within two meters of

the bottom; the remaining three are 3—4 meters above

the bottom (see Table II). While it is possible that the

approaching camera and lights aroused the specimens from the bottom, the attitude of the animals

with outstretched arms in many photos, as well as the

lack of a tell-tale puff of sediment (as is frequently

noted in photographs of deep-sea benthic fish), suggests that this is not the case in these photos.

Two photographs (Figures 12 and 29) show specimens in close proximity to the compass and magnetometer; the specimen in Figure 12 is 2 meters

above the bottom and that in Figure 29 is 3—4 m

above the bottom. A stereo pair in our files (BBIII—

1-123-427 and BBIII-1-13-432) shows a specimen

just over 2 m above the bottom and within 1 m of the

compass at the same level. Figures 25 and 26 depict

a specimen 3—4 m above the bottom and only 150 cm

from the camera. Only one specimen which is more

than 2 m off the bottom does not appear to be in close

proximity to the equipment. This seems to suggest

that these specimens may have been attracted further

off the bottom by the camera vehicle. While this observation could merely be a sampling bias due to a

reduced areal coverage close to the camera, it is

noted that specimens closest to the equipment (Figures

12, 25, 26, 29) exhibit attitudes that no other specimens show.

On the basis of current photographs and previous

experience with trawls, it seems reasonable to conclude that at least some cirrate octopods (exclusive

perhaps of Opisthoteuthidae) are indeed benthopelagic. Furthermore, the gelatinous consistency of

these cirrates suggests that they are neutrally buoyant,

which would allow them to "float" above the bottom; and their fragile structure is more similar to

that of a bathypelagic cephalopod than to that of a

benthic form. Finally, we have no evidence to even

suggest that these animals do live on the bottom.
16 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

The term benthopelagic was introduced by Marshall and Bourne (1964:226, 237, 240) to apply

to species of deep-sea fishes with swimbladders that

are able to attain neutral buoyancy and to hover and

swim over the deep-sea floor. Marshall (1965:302)

extended the definition: "Benthopelagic fishes (and

other organisms) are those that swim freely and

habitually near the ocean floor." This concept, for

fishes however, was introduced earlier by Marshall

(1960:97 et seq.). The term applies equally well to

the cirrate octopods which are able to remain off the

bottom by "hovering" or by normal swimming techniques.

DEPTH DISTRIBUTION

All known records of cirrates are from open nets except one closing net capture of Grimpoteuthis (Robson, 1924:682), and with only one known exception

(Pereyra, 1965:429), these nets fished on the bottom.7

 This, of course, does not preclude the possibility of capture higher up in the water column. Since

our photographs indicate that the species of Cirroteuthis that we are concerned with is benthopelagic, we infer that at least some of the other cirrates

share a similar habitat. If this is so, then depths of

capture are assumed to approximate the recorded

bottom depths. With these conditions in mind, the

depth records for cirrate octopods in general range

from 125 m to 2,251 m for Opisthoteuthis (Pereyra,

1965:429; Verrill, 1885:446)8 and from 339 m to

5,270 m for cirrates identified as species of Grimpoteuthis (Massy, 1916:186; Joubin, 1924:9).

Cirrothauma, originally known from about 1,500

m, is now recorded from the surface in the Arctic (in

7

 Robson (1932:2!, 83) misinterpreted Chun's (1914)

capture record of G. umbellata from Michael Sars Station

53. Robson thought that the specimen was caught in a

trawl at 1,430 fms (2,615 m), 137 fms above the bottom

depth of 1,567 fms (2,865 m). Actually, the Michael Sars

station data indicate that Station 53 was a benthic tow that

fished on the bottom over the depth range of 1,430-1,567

fms (2,615-2,865 m) (Murray and Hjort, 1912:xviii).

"During our search of the literature we have noted an

incorrect depth record which has been perpetuated since one

of the earliest citations of the genus. Verrill (1885:408)

reported and described the second-known specimen of

Opisthoteuthis agassizii Verrill, 1883, which was captured in

Albatross Station 2196 from 1,058 fms (1,934 m) off New

Jersey. In the list of deep-sea species on p. 446, Verrill

listed the depths for this species as 1,230 fms (2,251 m)

without referring to a station number. The 1,058-fathom

Voss, 1967:527) to a maximum of 4,136 m in the

Antarctic (see discussion and records in "Habitat"

section). Specimens of Cirroteuthis species have been

captured at depths that range from 2,342 m to

4,072 m (Apellof, 1892:3; Hoyle, 1886:56). Therefore, the large majority of captures of cirrates (except Opisthoteuthis) have been at depths in excess of

1,000 m.

All of the specimens from the Virgin Islands Basin

were photographed at a depth of 3,500 to 4,000 m.

Other specimens were photographed in the Thresher

search area at 2,500 m (Figures 8 and 11), in the

Blake Basin at 5,000 m (Figures 12, 13, 21 and 29),

SW of Bermuda at 4,250 rn (Figure 10), in the

Canaries Basin at greater than 3,000 m (Figure 24),

and on the Sohm Abyssal Plain at 5,200 m (Figure

28). The majority of the specimens represented here,

therefore, were photographed in depths that approach

the deepest known records of cirrate octopods.

During the past several years a number of NRL

photographic surveys have been made in depths of

less than 2,500 m. No photographs of cirrate octopods have been noted from the extensive collections

of photographs. The following table lists the area surveyed, the depth range, and the number of photographs taken:

Area

Blake Plateau

Tongue of the Ocean

Eleuthera

Western Mediterranean*

(Toulon)

Depth Range

(meters)

400-800

1500

200-1500

1000-2300

No. of Photos

7500

3000

2000

70,000

82,500

'Warm water (>13°C) may account for the absence of

cirrates here.

depth subsequently has been recorded as the deepest record

for O. agassizii (e.g., Robson, 1932:84, 167; Pereyra, 1965:

430), while the 1,230-fathom record has been overlooked.

(Robson, p. 167, had noted the 1,230-fathom record, but

apparently discounted it because no station number was

included by Verrill.) A check in the original dredging records of the Albatross (Townsend, 1901) indicates the source

of the confusion: Albatross Station 2196 actually was taken

at a depth of 1,230 fms (2,251 m), while the preceding

station, 2195, was taken at a depth of 1,058 fms (1,934 m).

Verrill had inadvertently recorded the wrong depth (and

the wrong latitude) and introduced a 317-m error in the

depth distribution of O. agassizii. The correct station data,

from Townsend (1901:395), are as follows: Albatross Station 2196: 6 Aug. 1884, 39°35'N, 69°44'W, Bottom temperature 38°F, 1,230 fms, green mud, LBT (large Blake

trawl).
NUMBE R 12 1 17

On the basis of photographic data and capture records in the literature, it appears that these cirrate

octopods are most abundant at depths in excess of

about 2,300 to 2,500 m and that they range beyond

5,000 m.

SIZE

The cirrate octopods that have been recorded in the

literature are, in general, rather small. Rarely have

specimens been recorded greater than 30 cm in total

length

 9 and most are around 20 cm total length or

smaller (see Robson, 1932). The largest cirrate on

record is the holotype of Cirroteuthis magna Hoyle

which measured 115.5 cm in total length (Hoyle,

1886:58). Robson (1932:154) mentioned a large

specimen of Grimpoteuthis species taken by Discovery that "may have been 3-4 feet long" (91—122

cm), but it was "lost overboard."

Measurements of preserved specimens of the semigelatinous cirrate octopods are particularly suspect

since, in time, specimens undergo a great amount of

shrinkage in preservative (alcohol). This problem

was mentioned by Verrill (1885:406-^07) in comparing preserved with fresh specimens, and later

by Robson (1932:159), who, after a period of several years, remeasured a specimen and noted up to

about a 23% reduction in size. Observations by recent workers indicate that shrinkage can be more

severe than that (R. Young, E. McSweeny, pers.

comm.; C. F. E. Roper), and Voss (1967:522)

claimed that it reaches 50% of its original size.

The size of the photographed specimens varies

considerably. The shadow geometry technique for calculating size is discussed in an earlier section (p 7).

Since it is not always possible to measure directly the

total length of the specimens in the photographs, the

calculated sizes (the greatest diameter across the

outstretched web and arms) have been interpolated

to a measurement of total length where feasible.

From measurements in the literature and from certain photographs (Figures 8, 9, 11, 13, 14) it is estimated that the arms comprise about 2/3 of the total

length of the animal and the body (mantle and head)

the remaining i/s- So, if one value is known, an approximation of the total length can be made. If the

photographed specimen has the arms and web

straightened out to its fullest extent normal to the body

axis, the arm length is taken to equal one-half the

calculated size less the body radius, and this value accounts for two-thirds of the total length. (Where arm

tips are curled up, arm lengths are extrapolated by

estimating the amount of curl and adding that to the

measured diameter.) Table III shows the calculated

size in the greatest dimension and the estimated or

interpolated total length.

In the photographs where measurements are possible, the estimated total length of specimens ranges

from 10 cm to 128 cm (4 to 50 inches). Four specimens are in the 90-103 cm (35-41 inch) range. The

largest span across the arms is about 170 cm (67

inches). This specimen, at a total length of 128 cm,

represents the largest known cirrate octopod to be

recorded (Figure 24). The literature to date records

predominantly small specimens, but the photographs

indicate that specimens of a meter or longer in total

length and with arm spans approaching a meter and

one-half are relatively common. As larger nets are

used in deep-sea benthic sampling, large specimens

of cirrate octopods should become more common in

collections.10

LOCOMOTION

Previous studies speculating on the mode of locomotion by cirrate octopods have assumed, on one hand,

that cirrates are ineffectual swimmers owing to weak

funnel development, gelatinous consistency of mantle

and funnel tissues, and reduced or absent mantle

opening. It has also been suggested that cirrates use

their fins and webs for providing locomotion, or that

the fins are merely balance organs, and the web is

used as a net for securing food. The lack of observations on living specimens has hindered a satisfactory

interpretation of the various adaptations that may

have a locomotory function, e.g., the web and the

fins, as well as the mantle and funnel. By 1932, at

least, Robson (pp. 22, 28, 57) was of the opinion

•Total length is measured from the posterior tip of the

body (mantle) to the tip of the longest arms, where the

arms are extended straight anteriorly parallel to the body

10

 It is suggested to potential collectors that cirrate octopods be fixed and preserved in a 7—8% solution of formalin

(buffered fresh water or sea water). Alcohol should not be

used if at all possible since it dehydrates the semi-gelatinous

tissue, so that specimens rapidly become shrunken and distorted. Specimens can be frozen if formalin is unavailable.
18 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

TABLE III.—Sizes of Citrate Octopods (cm)

Figure

7 ....

8

9

10 ....

11 ....

12 ....

13 ....

14-15

16

17 ....

18

19 ....

20 ....

21 ....

22 ....

23 ....

24

25-26

27

28

29

30-33

Calculated

Size*

50

103

_

26

64

17

43

_

25

13.3

_

13

98

25

125

53.5

170

111

36.6

_

48

-

Estimated Diameter

Arms Normal to Axis

_

_

_

_

_

_

35

19

_

17

129

35

146

59

170

120

46

_

64

30c

Estimated Total

Length

50

103

_

26

64

17

43

-

24

12

-

10

90

26

102

39

128

90

32

75b

• 48

22

a

 The various techniques employed for determining size

are discussed in the section on Photogrammetry (p. 6).

*> Estimate by C. D. Hollister.

c Estimate by R. R. Hessler.

that the cirrate octopods use their large webs for swimming. Earlier, Verrill (1882:373) had mentioned

that the deep-living non-cirrate octopod, Bathypolypus arcticus, swims by a pulsating or opening and closing motion of the arms and web. A similar mode was

suggested for Opisthoteuthis by Ijima and Ikeda

(1895:329) on the basis of their morphological studies and again by Berry (1952:184).

Direct observations on living material were reported for the first time by Pereyra (1965:430)

who observed Opisthoteuthis californiana in a shipboard aquarium. Pereyra established that Opisthoteuthis does use the interbrachial web in locomotion by

opening and closing the web in a manner analogous

to the movement of a jellyfish. Ejections of water

from the funnel are simultaneous with the contraction

or closing of the web, but Pereyra felt that this aided

little in the overall movement. The fins were very active primarily as balance and orientation structures,

and secondarily they appeared to aid in movement

(p. 437).

Swimming behavior in Vampyroteuthis infernalis

also has been observed (R. E. Young, pers. comm.).

Although Vampyroteuthis is not an octopod (it belongs to a separate order—Vampyromorpha), its

general appearance is quite similar to that of cirrate

octopods. It is entirely bathypelagic. According to

Young, three methods of swimming have been observed in Vampyroteuthis: (1) moderate swimming with arms pointing forward in the direction of

motion and propulsion provided by the fins; (2)

rapid swimming or escape reaction with a medusoid

action of the arms and web; (3) slow swimming with

water ejection through funnel and fins spread as stabilizers. Young stated that the first is the primary

method, while the second is rarely used; the third

method needs verification.

When the series of photographs that are presented

here were originally accumulated, little could be made

of the several positions depicted. With the exception

of Figures 14, 15 and 18, no sequential shots of

octopods were made; therefore, each of the remaining photographs represents a different specimen.

While the large number of specimens is interesting in

itself, the near absence of sequential shots makes it

difficult to determine the functional significance of

the various individual positions represented in the

photographs. Furthermore, in view of Pereyra's

(1965:436) observations that Opisthoteuthis completes a stroke cycle once every four seconds or more

rapidly, it is very unlikely that sequential shots taken

once every 10 seconds would record parts of the

same stroke cycle in cirrates. Since all specimens

were photographed above the bottom and since no

small organisms are visible in the photos showing

specimens with outstretched arms and web, we assume that the octopods are not in the act of feeding

per se but are swimming, hovering, or drifting above

the bottom, perhaps in a "hunting" position.11

A system of locomotion has been proposed on the

basis of the photographs. We conclude that several

11

 A study of recently acquired WA photographs from the

BLB (June 19, 1971) reveals two specimens each of which

was photographed twice. In both instances the interval

between exposures was 16 seconds. The cirrates remained in

essentially the same umbrella attitude and position relative

to the bottom as the towed "fish" approached and passed

above. This observation lends additional support to our

thesis that a hunting or drifting mode is utilized by cirrates

in the open umbrella attitude and that the animals usually

appear undisturbed by the "fish."
NUMBER 1 2 1 19

styles of locomotion are employed either singly or

concurrently: (1) the water-ejection (jet propulsion) type typical of other octopods, (2) the pulsating type using the web and arms, and (3) the

droguelike or umbrella phase utilizing outstretched

web and arms.

Water-ejection style.—This type of locomotion,

typical of other cephalopods, apparently occurs in the

cirrate octopods as well. The propulsive stroke, as

illustrated in Figures 7 and 8, is characterized by contraction of the mantle which forces water out of the

mantle cavity through the funnel, and results in a

true jetlike action that generally propels the animal

body-end first. While the relatively small mantle

cavity in these octopods probably does not exchange

a large volume of water with each pumping action, a

FIGURE 7.—Cirrate octopod in typical jet propulsion or

water-ejection swimming mode with mantle contracted, arms

in streamlined posture, and fins wrapped ventrally just posterior to left eye. An image of the photographic data partly

overlaps primary image. Table II presents additional information on Figures 7-33. (NA.3480.VIB) (The legends to

Figures 7-53 terminate with a parenthetical abbreviated

code which signifies: type of camera, depth of bottom in

m, and location. Length of scale mark on photographs equals

30 cm.)

large volume of flow would not be necessary to propel an animal that is neutrally buoyant or nearly so.

Simultaneous with, the ejection, the fins are brought

down (ventrally) in a stroke that terminates with the

fins wrapped tightly around the ventral surface of

the body. The arms are held tightly together to form

a surface of favorably low hydrodynamic drag. The

webs are completely concealed in the tightly held

arms. In these figures, the body is noticeably contracted as water is expelled (particularly Figure 7) in

contrast to the fuller, more rounded bodies in other

figures (e.g., Figures 20, 25). This propulsive ejection

stroke may occur following an initial pulsating

stroke, and it probably is used when more rapid locomotion, such as an escape reaction, is required.

Between propulsive ejections, a short glide period

occurs during which the arms are relaxed somewhat,

particularly at the tips, and the fins straighten out

perpendicular to the body. Figures 9, 10, 11, and 12

illustrate this glide mode. During the glide mode the

mantle expands and draws water into the mantle

FIGURE 8.—Cirrate in water-ejection mode. Sea urchin in

lower right provided a known size reference for determining

size of octopod. (TH.2500.NEC) (Bottom photograph

courtesy of J. Lamar Worzel)
20

SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

FIGURES 9-12.—9, Swimming cirrate with fins extended probably as stabilizers during a glide.

Specimen executing a "right-hand" turn. (NA.3620.VIB). 10, Photo of swimming cirrate

from starboard-looking camera of a trimetregon arrangement. Center (vertical) camera photographed compass striking bottom at uniformly sized linear depression (bottom), providing a

measure of the shadows of gliding cirrate and of camera altitude. Distance between shadows

was used to determine camera-to-cephalopod range which permitted calculation of animal's

size. On the bottom are a clump of Sargassum sea weed (lower right near depression), numerous

burrows and mounds, and fan-shaped radial lebensspuren (upper left). (NA.4250.BDA).

11, Attitude and shadow of cirrate with extended fins suggest an upward glide from a position

close to the bottom. The rocks are characteristic of this site at the top of the continental rise off

New England (see also Figure 8). (NA.25OO.NEC). 12, Curate at uncommon altitude above

bottom (2 m) and its position between instruments suspended from camera vehicle suggest a

possible attraction to the equipment. (WA.503O.BLB)

cavity. Possibly minor, more gentle ejections occur

during this period so that the animal can maintain

course and altitude; the large fins may aid in this

function. The specimen in Figure 9 with outstretched

fins is arched as though it were making a right-hand

turn.
NUMBER 12 1 21

14

k

15

FIGURES 13-15.—13, The dorsally extended fins on this cirrate may indicate the onset of a

downward stroke or possibly completion of a recovery stroke. Note distinct coloration at base

of the arms not accountable as shadows (see also Figure 10). (NA.5030.BLB). 14, The cirrate

in this and the following photograph is believed to be employing a water-ejection mode of locomotion at a calculated speed of 1.2 knots. (WA.3990.VIB). 15, The light-colored object

at left edge of this and preceding figure is a Shipek sediment sampler which was suspended

from the lead end of the vehicle. (WA.3990.VIB)

The cirrate in Figure 13 is in the water-ejection

phase with closed arms. The fins, however, are extended dorsally rather than ventrally, judging from

the location of the bases of the fins (compare, e.g.,

Figure 7 and 9) and the absence of any indication of

the funnel. The far-dorsal extension of the fins may

represent the initiation of a downward fin stroke,

or the completion of an upward stroke.
22 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

FIGURES 16-18.—16, Attitude of cirrates in this figure and in Figures 17 and 18 may represent

initiation of or full recovery from a pulsating stroke (see text). This position with curled arms

nearly perpendicular to the bottom is typical of the smaller specimens photographed (see Table

III). (NA.3660.VIB). 17, This small cirrate may have gone unnoticed had it not been for its

distinctive shadow (19 cm estimated diameter). The small (0.8 by 0.4 mm) size of the original

image on the negative indicates the great clarity of the water in the Virgin Islands Basin. (NA.

3770.VIB). 18, Montage of two photographs taken at a 12-second interval. The similar positions and apparent lateral progress suggest that the cirrate is in the same stage of the pulsating

stroke cycle or is holding a fixed position. (NA.3790.VIB)

Neither the interbrachial nor the intermediate webs

seems to play an active role in this dynamic, waterejection mode of swimming.

Figures 14 and 15 are sequential shots that indicate

the progress of a specimen across the bottom in the

30-second interval between shots. Using the distance
NUMBER 1 2 1 23

traveled and the known towing speed of the camera,

the average speed of advance of the octopus across

the bottom is calculated to be about 63 cm/sec, or

about 1.2 knots. The arms are in nearly the same

anteriorly directed position in both photographs, so

that it is difficult to determine which method of propulsion is being employed. Unless both shots were

taken at about the same position during the pulsating cycle, it seems probable that the water-ejection

method is being employed, especially in view of the

apparent speed of the animal.

Brundage et al. (1967, Figures 6-19 and 6-20)

published photographs of two swimming organisms

at 2,500 m in the vicinity of the Thresher. The specimens were tentatively identified as a "nektonic octopod," but more precise identification was impossible

at that time. Our present experience based on the

several photos now available leads to the conclusion

that both earlier specimens were the same type of cirrate octopod that occurs in the current series. Each

specimen is in the water-ejection mode of swimming.

An additional unpublished photograph of the specimen in Figure 6—20 permitted calculation of its speed

across the bottom as about 0.25 knots.

Pulsating style.—The pulsating phase begins as

the arms are curled or arched back aborally, so that

the plane of the basal portion of the arms and the interbrachial web is perpendicular to the longitudinal

axis of the body and the distal portion of the arms

are arched posteriorly so that the tips are nearly in line

with the posterior end of the body (Figure 16, 17,

18). The interbrachial web is contracted proximally

along the arms and greatly reduced in surface area

as the arms are curled back. The intermediate webs

form a broad, tightly stretched membrane between

the posteriorly arched arms and the contracted interbrachial web. The large fins, although not visible in

photos 16, 17, and 18, probably are arched dorsally

to the maximum extent of their recovery (as in

Figure 13).

The propulsive stroke begins as the arms are

brought anteriorly through an arc; the down-stroke is

initiated from the base of the arms and is carried out

smoothly to the tips. The arm tips arch and straighten

laterally, thus reducing the intermediate webs. This

action also pulls the interbrachial web distally along

the arms and expands its surface area. The fins swing

ventrally in their stroke, providing stability and

balance.

The stroke continues as the arms pass through the

perpendicular and curve anteriorly. The interbrachial

web remains expanded to its maximum surface area

so that only the tips of the arms are visible; the intermediate webs remain contracted. The fins have

moved well ventrally in their power stroke.

The propulsive stroke ends as the arms swing together into a straight, anterior position, bringing the

arm tips close to one another. The interbrachial web

is relaxed, and the fins have completed their stroke

and are wrapped ventrally around the body. During

the pulsating stroke it seems probable that a simultaneous expulsion of water from the funnel would

take place, although this cannot be detected in the

photographs.

The arms arch posteriorly for the recovery stroke

while the interbrachial web remains relaxed, so that

as the arms and web sweep in the direction of motion

of the animal—a minimum of surface area—a minimum resistance is offered. The fins move dorsally in

their backstroke. All components return to the original positions.

Figure 19 may represent a stage of the return

stroke since the interbrachial web is deeply billowed

anteriorly (orally), a condition that would result as

the arms are swept posteriorly. The same configuration could also occur during the transition between

water-ejection and drogue modes.

No photographs are available that confirm the

steps between the radial position of arms and web

(i.e., arms and web perpendicular to the body axis)

and the completed power stroke with the arms together. It is possible that the pulsating mode may

consist of shorter strokes that begin with arms curled

posteriorly and end with straightened arms and expanded interbrachial web perpendicular to the body;

each pulse may be followed by a short period in the

drogue position.

If the complete pulsating technique of swimming

does occur in cirrates in the manner that has been

observed in the related Opisthoteuthis and in Vampyroteuthis, complete photographic confirmation is

lacking. With the exception of Figure 20, and to a

lesser extent Figure 21, no photos show the interbrachial web strongly billowed in the posterior direction which would be expected during the powerstroke

—especially as the extended arms pass anteriorly

through a plane normal to the body axis. The interbrachial web in Figures 20 and 21 is billowed, but the
24 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

FIGURE 19.—A stage in the recovery portion of the pulsating

stroke is suggested by the inward curve of the arm tips and

orally billowed interbrachial web. (NA.3620.VIB)

arm tips are strongly curved posteriorly (prior to the

horizontal position), and the intermediate webs are

greatly expanded.

In the absence of the photographic evidence we

have less confidence in the existence of a full-stroke

pulsating mode than we do in a short-stroke pulsation and in the water-ejection and the droguelike

modes.

Droguelike or umbrella style.—Several photographs show the arms* stretched out perpendicular to

the body axis and the web almost completely or fully

expanded (Figures 22—27 and others in our files).

The plane of the brachial crown in these specimens is

parallel, or nearly so, to the bottom, and all specimens except the one in Figures 25 and 26 are within

1 meter of the bottom. The relatively large number

of photos of specimens in this particular position,

rather than in other possible positions to be expected

during the pulsating phase, suggests that the cirrates

are able to maintain a more passive attitude The outstretched arms and expanded web certainly create a

large surface-area-to-weight ratio which would further enable a nearly neutrally buoyant animal to

maintain a passive or drifting position above the sea

floor with a minimum expenditure of energy.12 Both

the buoyancy and viscosity

 13

 of cold water make a

droguelike or umbrella style of locomotion more effective than in warm water.

As most specimens in the droguelike position are

close to the bottom, this attitude probably represents

a food-hunting mode. If the bottom were approached

too closely, the animal could regain altitude by gently

pulsing the arms and web or by use of the fins. The

erect cirri on the outstretched arms, as in Figure 20,

which may have a sensory function for food gathering,

would most effectively cover a maximum area just

above the bottom where small planktonic organisms

may concentrate.

The hunting-drifting mode is further suggested by

the absence of puffs of fine sediment which surely

would be present if the animals in the photos had

just left the bottom. The passive droguelike mode

could begin with a short pulsating movement of the

arms which serves to gain altitude for the succeeding

drogue phase, or it could be integrated with the

dynamic ejection mode.

Certainly a few feet of good quality motion picture footage of some of the specimens shown here

would answer many questions about cirrate locomotion. The large number of still photographs, however,

has enabled us to suggest a plausible explanation of

attitudes in this cirroteuthid in terms of locomotion.

We believe that the photographs demonstrate several

points: (1) typical octopodan water-ejection locomotion occurs; (2) a pulsation mode of swimming occurs

occasionally in these cirrate octopods (somewhat

11 Cephalopods, in general, are negatively buoyant and

must either swim continuously or possess a buoyancy mechanism if they are to remain at their level in the ocean.

Several buoyancy mechanisms have evolved in the cephalopods including gas vessels, gelatinous tissues, light-weight

ammonium ions (see Den ton and Gilpin-Brown, in press)

and oil reservoirs (Roper, personal observation). Cirrate

octopods have no gas vessels or oil reservoirs, but they are

very gelatinous. Whether they concentrate ammonium ions

has not been established experimentally, but Pearcy (personal communication) has observed that freshly caught

cirrates have gelatinous arms that appear similar to the

NH4Cl-filled ventral arms of Chiroteuthis.

13

 Viscosity doubles during a temperature change (pressure effect negligible) from 30°C to 3°C (Dorsey, 1940:

182-188).
NUMBE R 12 1 25

20

FIGURE 20.—The erect cirri, clearly visible on most arms, probably have a sensory function in

hunting for prey. (NA.397O.VIB)

similar to that observed in Opisthoteuthis) ; (3) a

passive droguelike attitude is common with outstretched arms and interbrachial web, probably with

a hunting function—the umbrella is held in an open

attitude such that any natural water movement might

act to transport the animal just above the bottom;

(4) the interbrachial web and the intermediate webs,

in concert with the arms, function as the driving

force of the pulsating movement and as the planing

surface during the drogue phase.

CIRRI

The function of the papilla-like cirri on the arms of

cirrate octopods has long been a topic of discussion

among cephalopod workers. Suggestions in the literature for their function include: tactile or ciliary for

setting up currents to carry food to the mouth

(Hoyle, 1886:56); sensory (Meyer, 1906:201);

tactile (Abel, 1916:27). Robson (1932:120) suggested, though not too strongly, that the cirri may be

the homologues of the trabeculae or Seitenbrucke

that support the protective membranes in decapod

cephalopods. Berry (1952:187) suggested that the

cirri are used to sweep microplankton or detritus

down the disk toward the mouth of Opisthoteuthis.

One photograph in the present series (Figure 20)

shows the cirri. The distal position of the arms are

curled back aborally and the cirri appear to stand

erect and nearly perpendicular to the surface of the

arms. Little else can be added, except that perhaps the

erectness of the cirri may suggest a tactile-sensory

role. The tips of the arms on the swimming specimen

in Figure 9 are shown very clearly, but no cirri can

be detected.

Since the cirri appear to be erect when the arms and

web are expanded, perhaps they function as sensory

probes during the search for prey. Possibly the cirri

act as receptors to detect movement of water displaced by potential prey organisms. As such, the cirri

would have the maximum sensitivity when the octopod was not moving, that is when it was drifting with

outstretched arms. If prey were detected in this manner, it could be effectively enveloped by the out-
26 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

FIGURE 21 .—Light-colored aboral surface on interbrachial

web and dark arms seen here was noted on five of the six

specimens photographed with open umbrellas in the Blake

Basin. Dark banding on web sectors nearest top and bottom

of photo is apparently an effect of light and shadow rather

than true coloration (NA.5110.BLB)

stretched arms and web in a fashion similar to preycapturing by shallow-water octopods.

Again, more observations, including histological

studies, are needed to determine the function of the

COLORATION

The coloration of preserved specimens of cirrates

has been described variously as being from cream

white to black, but mostly in hues of red, purple, and

brown (see Robson, 1932). While specimens preserved in alcohol and even in formalin lose their true

lifelike colors, some coloration does remain and the

relative intensities of the coloration on different parts

of the body generally persist. Where color is recorded, for instance, most cirrates have a much more

darkly pigmented oral surface of the web and arms.

The photos presented here also indicate variation in

shading, some of which may be attributable to the distance the specimen is from the light sources, to the

angle of the specimen in relation to the light rays, and

to differences caused by backscattering from the water column and reflection from the bottom. Other differences may well be natural, but we will restrict our

discussion to gross differences that persist regardless

of the size of the organism and location of the specimens relative to light, camera and bottom.

Deep-sea octopods apparently are not as well supplied with chromatophores as their shallow-water

counterparts, and they may lack them altogether.

Deep-sea cephalopods in general, however, tend to

have a basic nearly continuous covering of pigment

that may vary in intensity on different parts of the

animal. Meyer (1906:188-189) stated that Opisthoteuthis has no true chromatophores on the outer surfaces of the animal. The large pigment cells present

are not expandable and contractile. True chromatophores occur interiorly only on the intestine,

gonads and mantle cavity.

Differences in coloration14 are apparent in the

photographs. In this discussion of coloration we have

attempted to eliminate differences due to light and

shadow on the basis of our knowledge of the location

of the light source in relation to the location of the

specimen. In Figures 20, 23, 24, and 27 the body,

head, fins and arms are dark and the aboral surface

of the web is lighter, probably as a result of light reflected off the light-colored bottom passing through

the thin membranous web. The arms appear dark

because of their thickness and opaqueness in relation

to the web. The specimen in Figure 25 is well off

the bottom and close to the camera vehicle. The body

and fins, which appear to have an almost velvety texture, are dark; the arms are highlighted by the strobe

light; the web is lighter than the body but appears to

be pigmented nonetheless (this is true of Figure 22

also). Figure 26 shows the same specimen as does

Figure 25, but it is a double exposure and makes the

specimen look transparent. In Figures 14 and 15, the

body, head, and basal portion of the arms are light,

while the arm tips are dark.

14

 In a strict sense the use of "color" and "coloration" in

this discussion is inaccurate because all photos are black and

white prints. We assume, however, that the photos register

grades of shading in proportion to (intensities of) the pigmentation known to exist in cirrates.
NUMBER 1 2 1 27

23

FIGURES 22-24.—22, Open umbrella-like posture of cirrate in Figures 20-27 occurs in nearly

half of the cirrate octopod photos in our files. This posture is interpreted as a passive driftinghunting mode that requires little energy expenditure. (NA.377O.VIB). 23, Cirrate in droguelike mode with outstretched arms and web. Lack of resolution in this and other WA photographs from the Virgin Islands Basin is due to use of an aerial lens mounted behind a transparent hemisphere and not to unclear water. (WA.3710.VIB). 24, Largest cirrate octopod

known to date is seen in this photograph from Canaries Basin (170 cm estimated diameter).

Dark object (lower left) is probably a fragment of sunken algae (possibly Sargassum). (WA.

3500.CAB)
28 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

FIGURES 25 and 26.-25, The utility of an NA and WA camera combination is demonstrated in this

close-up view and the simultaneous

full view shown in Figure 26. Note

detailed marks and texture particularly on interbrachial web. Specimen only 150 cm from camera.

(NA.3730. VIB). 26, Double compass image and apparent transparency of cirrate are artifacts created

by double exposure caused by shutter malfunction. (WA.3730.VIB)

25

The specimens in typical swimming position (Figures 7 and 8) are very light; the arm tips in both

are pigmented and the body in Figure 8 shows dark

shading. The swimming specimen in Figure 9 has a

moderately to lightly pigmented body and head; the

fins appear pigmented around the edges but lighter

toward the bases. The aboral surface of the arms and

interbrachial web proximally are quite light, whereas

the surfaces of the arm tips and the border and oral

surface of the web are pigmented. The specimen in

Figure 11, although far less distinct, shows a similar

coloration. The body, head and proximal portion of
NUMBE R 12 1 29

FIGURE 27.—Smallest cirrate photographed in the droguelike posture (46 cm estimated diameter). It has a translucent web through which details of its own shadow can be

seen. (NA.377O.VIB)

the arms of the specimens in Figures 10 and 13 are

darkly pigmented; the distal tips of the arms are

lightly pigmented; the fins are light, with slightly pigmented borders in Figure 13. The relatively small

specimens in Figures 16—18 appear to be heavily pigmented.

In Figure 21 the body, fins and arms are darkly

pigmented; the web is very light and apparently

opaque.

The specimen in Figure 28 has a dark pigmentation

over the entire body with an elongate light patch on

the dorsal surface of the mantle at the base of each

fin. Similar light patches appear to be present also in

Figures 9, 10, possibly 16, 29 and others in our files.

The distal edge of the interbrachial web also appears

to be very lightly pigmented in Figure 28. Other light

patches on the left side of the specimen at the posterior end and along the head may be explained as

FIGURE 28.—This cirrate apparently had been injured,

judging from its torn interbrachial web and unusual markings along its left side. Photo from Heezen and Hollister,

1971, fig. 2.64 [specimen misidentified in figure and in text,

p. 86, as "vampire squid"], by permission of Oxford University Press (scale estimated by Hollister, pers. comm.).

(TH.5202.SAP)

damaged areas, since the web has a large tear distally

between left arms I and II.

Figure 29 shows a specimen in an unfamiliar attitude in that its oral surface is directed diagonally
30 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

away from the bottom; this represents the only photograph we have showing the oral surface of the brachial

crown complex. The dorsal surface of the mantle,

head, tips of arms and oral surface of arms and web

are darkly pigmented. The distal edge of the interbrachial web is lightly pigmented. The proximal suckers, where visible on four of the arms, also are lightly

pigmented in comparison with the surrounding tissues. Distal suckers are not visible so apparently they

match the pigmentation of the darker arms and web.

The dark pigmentation in the photographed specimens probably includes several shades of reddishor purplish-brown if it resembles that of most described material (see p. 26- Live Opisthoteuthis

californiana are a dark reddish-brown (Pereyra,

1965).

"Reverse coloration" has been described in some

animal groups. For instance, Hansen and Madsen

(1956:57 et seq.) discussed deep-sea holothurians

FIGURE 29.—Cirrate at calculated height of 4.5 m above

the bottom (see Table II) and only 10 cm below approaching compass. Note light colored suckers on oral surface of

brachial crown. (NA.5110.BLB)

that are a darker brown or purple ventrally than

dorsally. Hansen and Madsen (p. 56) present a translated quote from Ostergren (1938:89) which advances

the theory for deep-living (benthopelagic and pelagic) holothurians that the dark ventral surface absorbs light and gives protection from below, while

the same holds true for the light dorsal surface against

the bottom when viewed from above. According to

Hansen and Madsen (1956:56), "Most psychropotids and species of Paelopatides are of a violet color

and often with the ventral side the darker."

Forster (1967) described a new species of deepsea ray, Breviraja pallida, which is characterized in

part by a very pale brown dorsal surface and a dark

brown ventral surface (p. 284). At least three other

species of ray from deep water have the ventral surface more darkly pigmented than the dorsal surface,

although they are not as pale dorsally as B. pallida

(Forster, p. 286).

While it is difficult to interpret the large variety of

color patterns shown in the photographs, the following discussion presents an interpretation that seems

to parallel the observations concerning reverse coloration in some other animals cited above.

In most cirrates the oral surface of the web is more

heavily pigmented than the aboral surface. The oral

surface would face the bottom if the animal spread

open its arms and web while in the pulsating or

drogue modes of swimming, or preparatory to pouncing on prey. If viewed from below by bioluminescent

light, the only source of light at great depths, the dark

oral surface would not reflect light but instead would

absorb it and blend into the black background overhead. Similarly, if the animal were being approached

by a luminescing predator, either from below or horizontally, the outspread arms and web with very dark

oral surface, which would face the predator, would

blend with the dark background. The cirrate could

either splay the arms and web initially when perceiving an attack, then undergo the typical octopodan

escape reaction, or it could escape and then hang unseen in the water with dark oral surface of arms and

web spread out facing in the direction of the attacker.

Furthermore, cirrates entirely lack an ink-sac which

functions effectively as a defense mechanism in shallower dwelling incirrate octopods. The splaying of

the arms and blending into the dark background by a

cirrate would be the analog of the ink-ejection and
NUMBE R 12 1 31

blanching out of chromatophores to blend with the

light background of the shallow-water octopods. The

survival value of each technique seems well suited to

the particular habitat.

If these cirrates are lightly pigmented aborally or

dorsally, as indicated in some photos (Figures 7—9,

11, 14, 15, 21 and others on file), the light coloration

would also provide survival advantage when viewed

from above. The animal would reflect bioluminescent

light from above and would blend in with a lightcolored sediment in the background.

Functional coloration in deep-sea animals is an

interesting subject and one in which further investigation may shed light on other aspects of the biology of

these organisms.15

RELATIVE ABUNDANCE

Although it is difficult to derive a picture of true

abundance of a mobile benthopelagic deep-sea species, it is possible to get an idea of relative abundance

or population density of a species on the basis of a

large series of photographs from different localities

(Marshall and Bourne, 1964:226, 237, 240).

The technique of assessing deep-sea populations

by towing a camera about 5 m above the bottom may

provide more accurate estimates than deep benthic

sampling devices such as dredges, Blake trawls and

otter trawls. This would be particularly true of some

of the more mobile benthic and benthopelagic spe15

 This speculation concerning the observed coloration

pattern in cirrates, which is included here to stimulate interest and discussion about this phenomenon in some deepliving animals, must assume several points. First, sufficient

bioluminescent light must be available to make the countershading of value. To our knowledge no detailed studies exist

that give information about the quantity or quality of bioluminescent light on and just above the bottom of the deep

sea. Second, a predator, or predators, presumably fish, should

be large enough to be able to capture the octopods which

may exceed one meter in length, and should have eyes functional enough to utilize the available light to detect potential

prey (image formation is not necessarily required). While

the largest known deep-sea benthopelagic fish, brotulids of

the genus Parabassogigas, grow to a length in excess of 1

meter and have functional eyes, their weak tooth structures

indicate that they are scavengers rather than predators (D.

Cohen, pers. comm.). (Highly developed teeth, however,

would seem not to be requisite for ingesting the soft-bodied,

semi-gelatinous cirrates.)

cies, e.g. fishes, cephalopods and prawns, which may

be able to detect and avoid the nets. In addition,

firmly attached forms such as some sponges, crinoids

and anemones for example, may not get scraped off

the substrate. The camera tends to be indiscriminate

while nets are selective.

When the "fish" operates 5 m above the bottom

taking pictures at 10-second intervals, the photographs represent a discontinuous 4.5 meter-wide

swath across the bottom (each photo covers an area

of 3.1 X 4.5 meters). The areal coverage is similar to

that expected from a sampling device of equivalent

width, e.g. a 15-foot (4.5 m) Blake or otter trawl, but

the photographs are undoubtedly more representative; in addition to the losses due to net avoidance by

swimmers and to firmly attached organisms, it has

been shown that deep benthic sampling devices move

very erratically across the bottom (Aumento and

Lawrence, 1968:11).

We recognize, of course, the possibility that the

flashing light source, clicking sonars and other disturbances of the towed "fish," may attract or repel

some organisms. In the case of the octopods some

were photographed in the hovering position, apparently undisturbed; others were photographed in

typical jetting attitudes, possibly having been disturbed or attracted. If the instrument vehicle does

have a disturbing effect on the octopods, it is possible

that some escaped detection by the camera. The lack

of multiple photographs of the same specimen indicates that the octopods are not strongly attracted to

the camera vehicle.

We have series of photographs from four different

localities that can be used to estimate relative abundance. Only NA camera photographs were used in this

comparison. Although several WA photographs show

cirrates, these have been excluded from the calculation of abundance, because this WA camera does not

resolve sharply enough in the peripheral area to assure an accurate count. Areal coverage per unit photograph differed greatly throughout the series because of different camera altitudes and angles of bottom view. The Virgin Islands Basin and Blake Basin

series are almost entirely vertical views. Those from

Bermuda and Northeast Channel areas comprised

about two-thirds oblique and one-third vertical views

arranged in an overlapping format. The resulting bottom area covered resembled a bow tie in outline (see

Figure 6-2 in Brundage et al., 1967). In calculating
32 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

the area the assumption was made that the towed

instrument vehicle remained horizontal and that the

bottom was flat. The following table presents comparative data from only those NA films which were

of sufficient quality for examination for the presence

of cirrate octopods:

Locality

Virgin Islands Basin

Blake Basin

Bermuda

Northeast Channel

Average

Depth

(meters)

3900

5000

4300

2500

No.

Photos

5300

10,000

10,300

38,400

Total Area

Covered (km*)

.061

.187

.896

2.36

No. of

Cirrate

Octopods

6

6

1

3

Abundance

Value*

98

32

1.1

1.3

'Abundance value = No. cirrate octopods/kms.

The Virgin Islands Basin and the Blake Basin

have abundance values at least one order of magnitude greater than the other two areas where sufficient numbers of photographs are available for

study. The Virgin Islands Basin area is unique among

the four in being quite close to land (islands) and

being an enclosed, steep-sided basin with a relatively

shallow sill depth. The basin appears to have an internal anti-cyclonic circulation. Erosion channels produced by turbidity currents and subsequent density

flows are evident in some photographs (e.g., Figure

51). Perhaps a combination of these factors contributes to an unusual enrichment of the basin from

shoal water by organic material such as sea grasses

(Thalassia and Syringodium), mangrove leaves and

other debris, as seen in a number of photographs

(Figure 39, 43, 49, 52, 53) (see discussion on p. 42).

The Blake Basin is also enclosed, but the maximum relief of the sill above the 5,000-m deep basin

is less than 300 m (Pratt, 1968, pi. I). While this

readily distinguishes the Blake Basin from the Virgin

Islands Basin there are similarities which may account for the relatively high abundance value. Contour currents in the area north of the basin would

tend to transport plant debris southward into the

basin. Menzies and Rowe (1969:219) have suggested that such currents transport algae southward

on the slopes north of the Blake Outer Ridge.

Bathymetric contours directly north of the Blake

Basin indicate that a similar mechanism occurs in the

basin. We have a number of photographs in our

files which show both grass blades and Sargassum

clumps on the floor of the basin. We also have photographs of an erosion channel along which there is a

broad accumulation of plant debris, primarily Sargassum.

Finally, there is an apparent northward decrease

in the abundance value of cirrate octopods. Whether

this reflects geographic, topographic, trophic or some

other factors cannot be determined at this time.

ADDITIONAL CIRRATE PHOTOGRAPHS

After this manuscript was completed, we received a

set of very fine photographs of a single cirrate from

R. R. Hessler, Scripps Institution of Oceanography.

The photos were taken during a dive of the Woods

Hole Oceanographic Institution's submersible Alvin

at about 39°46'N 70°32'W (90 miles south of

Martha's Vineyard) at a depth of 1,300 m. We are

most grateful to Dr. Hessler for supplying us with the

photos and his observations, and we acknowledge

the WHOI deep submersible program.

The photographs were taken with an externally

mounted EG&G camera/strobe combination. Locality data are:

Alvin Dive No. 225, 26.IX.1967

Start of dive: 39°47.4'N 70°31.9'W

End of dive: 39°43.8'N 70°32.9'W

Depth: 1300 m

Pilot: Val Wilson

Scientists: Robert R. Hessler, George R. Hampson

Although the specimen appears to be a different

species than that shown in our other figures, the photographs are included here becuase they show features not observed previously and because of Hessler's informative direct observations of the octopod.

Observations.—The following is based on the ob-
NUMBE R 12 1 33

servations made by R. R. Hessler (pers. comm.).

The octopus apparently had perceived the submersible before the observers sighted the specimen.

When first observed out of a side port, the cirrate

was hanging motionless in the water about 2 m above

the smooth sedimentary bottom with its tentacles

and web spread out so that the oral surface faced

the vehicle. The plane of the arms and web was

oriented normal to the bottom, so the body was not

visible to the observers. The submersible was turned

so the specimen could be photographed with the forwardpointing cameras. The first photographs show

the cirrate with arms still in the spread-out position

(Figure 30) ; in later shots the arms are closed

(Figures 31-33). Once the submersible was turned

toward the octopod, the specimen could no longer be

seen by the observers, so direct observations of its

locomotion and behavior from that point on could

not be made.

Hessler estimated that the specimen was about one

foot in diameter across the outstretched arms, although size determination is difficult from a submersible without a scale reference.

The color of the cirrate was a "deep brownishred" over the entire surface of the animal. The suckers, as shown in Figure 30, were very light, almost

white—"actually a light cream color" (quoted from

Hessler). The photographs indicate that the color

intensity was nearly uniform over the entire animal.

The bottom depth of 1,300 m is considerably shallower than that of our other photographs, but it is

well within the range recorded in the literature for

cirrates in general.

Photographs (Figures 30-33).—In Figure 31 the

animal appears very long and slender with a short,

conical mantle. The fins are not visible as they are

tightly wrapped ventrally around the mantle. The

head is broader than the mantle, and the large right

eye protrudes from the surface so that the whitish

lens is clearly visible. The arms are very long and

held together so that the web is relaxed.

In Figure 32 the specimen is in much the same

position as in Figure 31, but this is a ventral aspect

that shows the fins wrapped ventrally around the

mantle with the right fin overlying the left. The tips of

the arms extend beyond the margin of the interbrachial web, and cirri are lacking from the visible

portions of the arm tips.

The funnel can be seen in the ventral view of the

specimen in Figure 33; it appears as a dark spot on

the ventral surface of the head nearly in line with the

anterior borders of the fins. The fins appear to be in

different positions: the right fin looks to be nearly

perpendicular to the body while the left fin is swept

further ventrally and appears to be rotated slightly

on its axis. This indicates the capacity for independent movement of the fins and that the fins may

serve as stabilizers in position-holding as well as driving oars in swimming.

In Figures 31, 32, 33, the specimen appears to be

in the more or less typical cephalopoden swimming

mode with arms held together in line with the body

axis and with fin action, and possibly water ejection,

used to hold position or to move slowly.

Figure 30 is an unusual shot of the entire oral

surface of the outstretched arms and interbrachial

web directed at the camera. The suckers in a single

row along each arm appear very light-colored in contrast to the dark background of the web. The location

of the mouth can be seen at the confluence of the

bases of the arms. The long cirri are clearly visible

along each side of the arms. They appear to originate

very near the proximal end of the arms and continue nearly to the level of the margin of the web

where they terminate, leaving the free distal tips of

the arms devoid of cirri.

The intermediate or secondary web, so frequently

visible in our other photographs, appears to be entirely lacking on the specimen in this set of photographs (4 published here, and 4 unpublished).

Initial observations and subsequent photographs

(Figure 30, plus one other in the series) reveal the

animal with arms and web outstretched so that the

plane of the oral crown is facing the vehicle and

camera. This may be a defensive attitude, as suggested

in an earlier section. Subsequent photographs (Figures 31-33 plus others in the series), taken when

the vehicle and camera were very close to the specimen, show the specimen in a jetting attitude heading

away from the camera, but making very slow progress.

Associated Organisms

ANIMALS

The series of photographs from the Virgin Islands

Basin contains a number of shots of organisms other

than cirrate octopods. During the operations the bottom structure ranged from a smooth, relatively finely
34 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

31

FIGURES 30-33.—30, View of oral surface of arms and interbrachial web of cirrate showing

suckers (white dots) and cirri along arms. (Photo and estimated scale from submersible Alvin;

R. R. Hessler) (NA.1300.MVS). 31, Swimming cirrate with fins folded ventrally. Note

bulging eye and lens. (Alvin photo; R. R. Hessler) (NA.1300.MVS). 32, Ventral view of

swimmnig cirrate showing folded fins and location of funnel (dark spot immediately anterior

to fin). {Alvin photo; R. R. Hessler) (NA.1300.MVS). 33, Ventral view showing fins expanded and location of funnel (dark spot on ventral surface of head between bases of fins)

(Alvin photo; R. R. Hessler) (NA.1300.MVS)
NUMBE R 12 1 35

;'f

34

3 6

FIGURES 34-37.—34, The large-headed, slender-bodied, unidentified fish was the most common fish photographed in the Virgin Islands Basin. (NA.3950.VIB). 35, An unidentified

species of the fish family Alepocephalidae. (NA.3810.VIB). 36, A species of Bathysaurus.

(NA.3870.VIB). 37, A brotulid near the edge of the field of view. (NA.3790.VIB)

sedimented bottom, to a coarse gravel and boulder

bottom, to deeply cut turbidity channels in compact

sediment, to undercut and exposed rock outcroppings

 i e

 along the steeply sloping portions of the

bottom. Photographs of the various habitats show a

variety of organisms—both attached and mobile

benthic forms, benthopelagic species, and lebensspuren.

" We define outcroppings as rocks that appear to be uncovered portions of larger rock masses as distinguished from

boulders that appear as isolated, unattached rocks.

Several different species of fishes were photographed. A common hindrance to the identification

of deep-sea fishes from photographs is that the majority of photos view the fish from the dorsal surface,

an aspect from which ichthyologists seldom examine

their material. The most commonly photographed

fish from the Virgin Islands Basin (Figure 34) is

unidentifiable because it is always seen in dorsal

aspect, from which it looks like any of several different groups. (In tabulations we refer to this as

"Big head", realizing that several species may be represented.) The unusual dorsolateral view in Figure
36 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

FIGURES 38-41.—38, A morid or deep-sea cod. (NA.3880.VIB). 39, A species of Ipnops. The

brilliant spot on the head is a reflection from the highly modified, nearly fused eyes. Note

accumulation of sea grasses on bottom. (NA.3780.VIB). 40, This unidentified species of

penaeid (or caridean) decapod crustacean was often photographed close to the bottom. (NA.

3880.VIB). 41, The galatheid crustacean to the right of compass vane is a species of Munidopsis. The dark rectangular shape is evidently a piece of waterlogged wood encrusted with

serpulid polychaete worms. (NA.3880.VIB)

35 shows a species of the family Alepocephalidae.

Other identifiable fishes include a bathysaurid (cf.

Bathysaurus) (Figure 36), a brotulid (Figure 37), a

morid (Figure 38) and an unidentified species of

Ipnops, a genus characterized by highly modified,

nearly fused, dorsally located "eyes" (Figure 39)

(Authority: R. H. Gibbs, Jr., G. Mead, N. B. Marshall, D. Cohen, J. Nielsen, pers. comm.). Most fish

were photographed swimming within a few centimeters of the bottom

Several photos of a species of penaeid or caridean

decapod crustaecean are available (Figure 40; I.

Canet, pers. comm.). This species appears to be

benthopelagic since all specimens (more than 50 in

two camera runs) were photographed just above the

smooth sediment of the open bottom. A commonly
NUMBER 12 1 37

seen crustacean was the galatheid Munidopsis (Figure 41; F. Chase, R. Manning, pers. comm.). This

photograph also shows what appears to be a piece

of water-logged wood settled on the sediment, heavily

encrusted with serpulid polychaete worm tubes

(M. Jones, pers. comm.). Galatheids are abundant

in some portions of the area (Figure 42) (not all

are verifiable as Munidopsis) and generally seem to

be associated with a solid substrate such as rock,

small boulders or wood; few photos show them on

the open bottom.

At least two species of elasopod holothurians were

FIGURES 42-44.—42, Galatheids were photographed primarily on or near firm substrates.

(NA.3850.VIB). 43, Holothurians common to the area were Psychropotes species (left) and

a laetmogonid (right). Note the density of sea grass fragments. (NA.3860.VIB). 44, A laetmogonid cuts a trail near a polyethelene wrapper. Animal trails have been traced on a series

of photographs over distances of several hundred meters. (NA.3880.VIB)
38 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

commonly photographed on the finely sedimented

open bottom generally devoid of rocks. Psychropotes

species and a species of Laetmogonidae (D. Pawson,

pers. comm.) occur together in an area of concentration of organic debris, consisting of sea grasses

(Thalassia and Syringodium [Cymodocea]) (Figure

43). Figure 44 shows a laetmogonid and its lebensspur across the sediment; evidence of man's contribution to the deep benthic environment also is present

in this figure.

Several photos show what appear to be anemones

(Figure 45), although a species of curved- and longspined echinoid cannot be entirely ruled out because

only appendages and no bodies are visible. Figure 46

FIGURES 45-47.—45, Tentacles of a sea anenome (or possibly a curved-spined urchin) protrude

from behind the center boulder in this varied cluster of rocks. (NA.3920.VIB). 46, A lightcolored anenome is attached to the upper edge of the dark boulder. (NA.3860.VIB). 47, Four

species of sponges are affixed to vertical edge of outcrop. Scale is for level area at bottom of

photo. (NA.3920.VIB)
NUMBER 12,1 39

shows another species of anemone or possibly a

solitary coral.

In some photographs showing rock outcrops and

boulders, attached organisms are very numerous, e.g.,

sponges, coelenterates and brachiopods. Figure 47

shows a partially scoured rock outcrop with four different species of sponge attached along the vertical

face (K. Ruetzler, pers. comm.). Most sessile organisms seen in numerous similar photographs are

located on the vertical face of the outcrops or boulders; seldom are organisms seen on the horizontal surface. This common orientation may be a response to

more favorable position in the slight currents or to

avoid sedimentation.

Many photographs (about 40 on a single camera

lowering) were taken showing one or more irregularly

shaped, debris-covered organisms at the end of a

lebensspur (Figure 48). The organism appears to be

a mollusk (J. Rosewater, J. Allen, pers. comm.), but

photos do not reveal sufficient detail to settle the question of whether it is a gastropod or a bivalve. A small

portion of light-colored material (shell?) is seen beneath or surrounded by each clump of plant debris;

the photo shows small tendril-like appendages extending from the periphery of the light material. Each

specimen and its accumulated "trappings" left a distinct meandering trail through the soft, sedimented

bottom. Some photographs show accumulated clumps

of plant debris, probably Sargassum, around which

are gathered numbers of these curious organisms and

their lebensspuren (Figure 49).

We have attempted to make an estimate of the relative abundance of some of the more commonly photographed motile, epibenthic and benthopelagic macroorganisms. The count estimate is based upon 2,500

photographs taken on a single run by the same

camera on 27 November 1969 with an average altitude of the camera of 4 m. The total area surveyed

by these 2,500 photographs was approximately 26,-

000 m2. The photographs were all located in the

SW hachured area of Figure 2. The following counts

were obtained:

Sea Cucumbers

Laetmogonidae—5 0

Psychropotes—54

Crustaceans

Shrimp—34

Galatheidae (including Munidopsis) —13

Fish

Ipnops—3

"Big Head"—5

Others—9

Other organisms17—7.

LEBENSSPUREN

The term "lebensspuren" is defined in its simplest

sense as ".. . structures in the sediment left by living

organisms" (Hantzschel, 1962:W178). The term

applies equally to fossil and recent tracks, burrows,

and other marks made by animals and plants on or

in the sediment. Although ''lebensspuren" has been

utilized primarily by paleontologists, it is a convenient, descriptive word that can apply to numerous

features seen in deep-sea photographs.

The surface sediment in the Virgin Islands Basin

appears ideally composed for revealing trails and impressions made by the benthos. The coarse, lightcolored and easily moved constituents of the sediment settle readily into depressions in the contrasting

darker background composed of finer sediment.

Holothurians were frequently photographed at the

end of plainly marked meandering trails (Figures 39,

40), which form complicated patterns extending hundreds of meters over the flatter parts of the area. Other

trails made by less easily identified organisms are

also common, e.g., Figures 48, 49.

Another common type of lebensspuren consists of

a radial arrangement of straight lines or grooves extending out from a shallow, round, central depression

(Figure 50). The radial pattern frequently encompasses a full 360°, but occasionally lesser arcs occur

(Figure 27). Invariably a smooth, widely conical

mound is located close to or within the radial pattern

of grooves. An indistinct depression generally can be

detected at the summit of the mound of sediment.

These lebensspuren are very abundant along the edges

of erosion channels, generally in rock-free areas

(Figure 51). Some, however, have been noticed on

large rock surfaces that have been mantled with a

layer of sediment.

Despite the abundance of the radial patterns in

bottom photographs, no organism or part of an organism responsible for the marks has been detected.

It seems likely, however, that they mark the location

of burrows, possibly of polychaete worms. The cen17

 Other organisms include 3 asteroid starfish, a lightcolored holothurian, and 3 unidentified dark animals that

may have been echinoids or sea anemones.
40 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

tral depression and mound arrangement in deep-sea

photographs, but not necessarily the radial patterns,

are reminiscent of some polychaete burrows found

on sedimented bottoms in undisturbed shallow waters. If this is so, then the central depression is the

entrance of the U-shaped burrows; the radial lines

(grooves) are made as the organism extends part

of its body and drags it back across the sediment,

presumably collecting food; the mound is the effluent

pile where ingested silt and wastes are deposited.

The large number of photographs that contain

these radial lebensspuren indicates that several different kinds occur. The radial lebensspuren photographed in the Virgin Islands Basin seemed to be

much more abundant than is indicated in the summary of such benthic features reported by Ewing

FIGURES 48-51.—48, White object (upper right) with light tendril-like appendages is part of

an unidentified animal, probably a mollusk, which drags accumulated bits of debris across the

bottom. (NA.3890.VIB). 49, Accumulations of plant debris were often photographed surrounded by lebensspuren (life-trails) and trailmakers (as that seen in Figure 48). This large

clump probably is Sargassum. (NA.3920.VIB). 50, Radial grooves extending out from a

central depression (light fan-shaped patch) were a type of commonly photographed lebensspuren (life-trail). (NA.3880.VIB). 51, Several radial lebensspuren on terraced side of

erosion channel. Note block of compact sediment recently calved from edge of upper terrace.

Scale mark to left is for uppermost terrace, to right for lowest level. (NA.3970.VIB)
NUMBE R 12 1 41

and Davis from the deep sea floor more remote from

land (1967, see especially Figures 24—53 through

24—63). These authors proposed a scheme of classification for lebensspuren.

PLANT DETRITUS

Several types of detrital plant material occur in the

photographs. Two different sizes of long, thin, grasslike fragments can be seen in nearly every bottom

photograph. The most common fragments are those

with an average width of 1.5 mm, while others between 6 and 12 mm in width are present in much

smaller numbers (Figure 52). The latter closely resemble the foliage leaves of the turtle grass, Thalassia

testudinum, which at maturity has a tendency to

break off just above the sheathed portion at the base

(see Tomlinson and Vargo, 1966:758 and Figures

9, 10, 11). The broad fragments are decidedly bladelike, while the thin detritus is usually curved and apFIGURE 52.—Wide grass fragment (upper right center) is

blade of Thalassia, while thin fragments are more abundant

Syringodium. A psychropotid holothurian lies at top of

photo. (NA.3850.VIB)

pears uniform in cross section throughout its length.

These thin fragments probably are pieces of manatee

grass, Syringodium filiforme, rather than the similarly

sized but flat shoal grass, Diplanthera wrightii. Both

of these grasses grow in the same shallow-water

habitat as Thalassia (Stephens, 1966:265; Welch,

1963). A survey of the shallow waters of the nearby

island of St. John revealed extensive areas of both

turtle grass and manatee grass with the latter dominant at greater depths, some even to more than 20 m

(Kumpf and Randall, 1961:548). H. J. Humm (pens,

comm.) has confirmed the identification of both

Thalassia and Syringodium fragments in our photographs (e.g.: Figures 39, 52, 53 and others on file).

No closely examined photograph from the Virgin

Islands Basin was found devoid of these detrital

grasses and a count of greater than 10 fragments per

square meter was typical in hundreds of photographs.

The large number of sea grass fragments in our

Virgin Islands Basin photographs is an order of

magnitude greater than those recorded from similar

depths in other works. Pratt (1962:495) presented

a photograph from the Puerto Rico Trench showing

two blades, and Menzies and Rowe (1969:219) reported highest concentrations of % to 1 blade per

photo at abyssal depths off North Carolina.

Clumps of a fucoid-type seaweed, probably Sargassum, were noted in several photographs (see Figure 49 and p. 32). Humm (pers. comm.) has concurred with the identity of Sargassum and also has

suggested that possibly some of the clumps may consist entirely or in part of some of the common large

red algae from seagrass beds, especially Laurencia.

Fragments and entire leaves, apparently of terrestrial origin also were photographed on several occasions. At least one of these is identifiable as a mangrove leaf (Figure 53), possibly from one of the

three common tropical species found on the nearby

island of St. John (Kumpf and Randall, 1961:551).

Plant debris also was noted in photographs from

the Blake Basin, particularly along an erosion channel. This consisted primarily of Sargassum clumps,

and, less commonly, of single blades of Thalassia.

The importance of shallow-water plant debris as a

source of food for the abyssal benthos has been suggested by a number of investigators (see Menzies, et

al., 1967:111). Mortensen (1938:225 et seq.) listed

a number of species of deep-sea echinoids collected

from as deep as 3,000 m that had gut contents consisting of plant material, some of terrestrial origin
42 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

FIGURE 53.—One mangrove leaf and probably a fragment

of a second can be seen in center of this view along with

many sea grass fragments. (NA.377O.VIB)

and some marine, such as fucacean algae. Mortensen

(p. 228) concluded that many deep-sea echinoids

are "facultative vegetarians" in regions where rich

plant material is available to be carried out to sea.

Moore (1963:1234) has pointed out the probable

significant importance of sea grass as a source of

energy for West Indian deep-sea organisms. The deposition of grass probably occurs continuously, but

it is expected to be especially heavy following storms

and hurricanes during which time great quantities of

grass are broken off or uprooted. Further indication

that deep-sea organisms ingest algae of shallow-water

origin was given by Okutani (1969:34) who discovered quantities of littoral and sublittoral "kelp"

in the stomachs of the deep-sea urchin, Hygrosoma,

from Sagami Bay and Oshima-Miyake Region, Japan.

Our photographs indicate that at least two species

of holothurians, a laetmogonid and Psychropotes

species, are relatively more abundant in those areas

where plant fragments are most numerous (Figures

43, 52). Another species, possibly an unidentified

mollusk, visibly utilizes plant material from the surface by gathering and transporting fragments. The

animal leaves a distinct trial in the soft sediment

(Figures 48, 49).

Several photos show clumps of seaweed, probably

mainly Sargassum, which are surrounded by conspicuous lebensspuren (Figure 49). Similar observations have been made from photographs taken in the

open Hatteras Abyssal Plain (Rowe and Menzies,

1969:536). Such clumps probably provide a concentrated source of organic material for foraging

benthic organisms in the enclosed Virgin Islands

Basin, either from the alga itself or from the organisms attached to it.

The point that we wish to emphasize is that there

seems little doubt that plant materials of shallowwater origin are utilized by deep-sea organisms, and

that the degree of utilization and the overall importance of this material in deep benthic food webs

previously may not have been properly appreciated

or emphasized.

BIOMASS

The Virgin Islands Basin appears to be a relatively

organically rich area judging from the photographs

available. Cirrate octopods are significantly more

abundant than in other areas sampled, and a high

incidence of other benthopelagic and benthic macroorganisms has been noted above.18

It is perhaps more significant that fragments of

plant material, especially sea grasses, were identified

in each one of the thousands of closely examined

photos from the Basin. Counts of up to 10 pieces per

square meter were recorded; this value is an order

of magnitude greater than previously recorded in

photos from other areas at comparable depths.

Certainly there appears to be a positive correlation

between abundance of plant material and abundance

of organisms in the deep sea. This correlation has

been discussed by, among others, Heezen, Ewing and

Menzies (1955:174) and Schoener and Rowe

18

 Several attempts were made to arrange to sample the

Virgin Islands Basin with deep benthic trawls in an effort to

capture specimens of cirrate octopods and other benthic organisms. After our own efforts to secure a vessel with adequate trawling capabilities met with little success, G. L. Voss,

Institute of Marine Sciences, Miami, kindly agreed to divert

the R/V Pillsbury to the Basin during a cruise to the Caribbean Sea in June 1970. Adverse circumstances prevented

trawling in the bottom of the basin at 4,000 m. One tow,

however, was made along the steep southern slope of the

basin. The net fished between about 400-2,000 m, and

while it caught no finned octopods, other forms of benthic

life were extremely abundant. Although the analysis of the

sample is incomplete, Voss (pers. comm.) has the impression

that the basin has a very rich benthic fauna that surpasses

the faunas from the same depth stratum in other areas

sampled by the Pillsbury during the current deep-sea biology

program aboard this ship.
NUMBE R 12 1 43

(1970:923) (see their references). Numerous observations are recorded in the literature, and more

have been made during deep-sea trawling activities

that strongly support the concept of the relationship

between plant debris and animal abundance.19

Our Virgin Islands Basin photographs indicate that

holothurians, for instance, are most numerous where

sea grass is abundant (Figures 43, 44, 52), and that

organisms and lebensspuren are abundant around

clumps of Sargassum (Figure 49).

The question of the nutritive value of sunken sea

grasses and weeds to benthic organisms and, indeed,

the question of whether these animals can utilize

plant material are important points that need answering. Some protoplasm remained in ectoproct

tests attached to Sargassum retrieved from stomachs

of deep-sea brittlestars (ophiuroids). This point led

Schoener and Rowe (1970:923) to suggest that the

nutritive value of Sargrassum to the deep benthos may

derive from the attached fauna rather than from the

alga itself. On the contrary, Vinogradov (1961:1441)

presented data indicating the degree of decomposition in pteropods at increasing depths; below 2,000—

3,000 m little or no protoplasm remained in the tests

as a source of food to benthic organisms. Although

pteropod tests were noted in the sediments of the

Virgin Islands Basin (see Table I), they probably

do not contribute food to the benthos. The situation

with other small organisms may be similar if the

transport is by passive sinking, commonly termed the

"rain" of dead organisms.

More rapid means of transport of organic material

to the deep sea do exist: (1) terrigenous material

that is rafted or current carried, and (2) near-shore,

estuarine, or terrestrial material transported by turbidity currents (Heezen, et al., 1955:176), or by

migrations of animals.

It is possible that both of these active transport

mechanisms function in the Virgin Islands Basin, but

"Neither plant debris nor organisms (visible in photographs) were found to be nearly as abundant in the Blake

Basin as in the Virgin Islands Basin. It is interesting, however, that out of a recent series of five camera runs, all

eight citrates that were photographed occurred during the

single run which traversed an erosion channel along which

was deposited a broad band of plant debris, primarily Sargassum. This run took place about a mile south of the area

covered by the other four runs, where no erosion channels

were photographed. We are not suggesting a direct correlation between abundance of plant debris and cirrate octopods.

the broad distribution of plants suggests that the

rafting or current-carried method is more important.

As pointed out on p. 9 there are data to suggest that

a cyclonic circulation occurs beneath sill level in the

basin. On the south side of the basin this circulation

would appear as a reversal of the westerly surface

flow. Sea-grass debris from the shallows on the north

coast of St. Croix would first be carried westward

until it sank beneath about 2,000 m, after which it

would be transported back towards the east, where

the relatively rich fauna was photographed. In addition, sinking organic matter, e.g., Sargassum and sea

grasses, from the north and east would tend to be

trapped by the relatively shallow sill at the western

end of the basin.

Many photographs taken at the base of the slope

show distinct erosion channels that probably are the

result of turbidity currents. Small-scale density flows

down the slope probably follow the channels and

carry in shallow-water materials. Several photographs

show small down-slope lineations of plant debris,

primarily sea grasses, accumulated along the edges of

rock outcroppings. Furthermore, the detailed acoustic

records show that a ridge approximately 200 meters

in relief, occurs along the base of the steeply sloping

south side of the basin (Figure 6). The ridge may

act as a dam to trap organic materials carried down

the slope.

In general the productivity in the surface waters

of the Caribbean Sea is regarded as relatively low

(Fleming and Laevastu, 1956:183), and this is reflected in the midwater fauna. The benthic fauna is

rich in near-shore areas along the continental margins where enrichment from river runoff occurs. We

suggest that the Virgin Islands Basin, isolated from

continental enrichment but exposed to Atlantic water intrusion through the Anegada Passage and to sea

grasses and organic materials from the neighboring

islands and reef flats, serves as a bowl of concentration of organic materials with a resultant unusual

abundance of deep-sea benthic and benthopelagic

organisms.

Literature Cited

Abel, O.

1916. Paldobiologie der Cephalopoden aus der Gruppe

der Dibranchiaten. 281 pages. Jena: Gustav

Fischer.
44 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

Andrews, F. A.

1965. Search Operations in the Thresher Area—1964.

Section I. Naval Engineers Journal, 77(4):549-

561.

Apellof, A.

1892. Teuthologische Beitrage. III. Bemerkungen iiber

die auf der norwegischen Nordmeer-Expedition

(1876-78) gesammelten Cephalopoden. Bergens

Museums Aarborg, 1:1-13, 1 plate.

Aumento, F., and D. E. Lawrence

1968. Photographic Control of Deep-Sea Dredging.

Geological Survey of Canada Paper 68-9. 13

pages.

Berry, S. S.

1952. The Flapjack Devilfish, Opisthoteuthis, in California. California Fish and Game, 38(2): 103-

188.

Bjerkness, J.

1960. Ocean Temperatures and Atmospheric Circulation. World Meterological Office Bulletin,

IX(3): 151-157.

Boyce, R. E.

1964. Simple Scale Determination on Underwater Stereo

Pairs. Deep-Sea Research, 11:89-92.

Brundage, W. J., Jr.

In press. Scale in Single Ocean Floor Photographs by

Shadow Geometry. Photogrammetric Engineering

Journal.

Brundage, W. L., Jr., and R. B. Patterson

1966. Ocean Bottom Photography from a Deep Towed

Camera System. Journal of the Society of PhotoOptical Instrumentation Engineers, 4:156—160.

Brundage, W. L., Jr., C. L. Buchanan, and R. B. Patterson

1967. Search and Serendipity. In J. B. Hersey, editor,

Deep-Sea Photography. Pages 75-87. Johns

Hopkins Oceanographic Studies (3).

Brunn, A. F.

1943. The Biology of Spirula spirula (L.). Dana Report, number 24, 46 pages. Copenhagen.

Buchanan, C. L., and R. Isaacson

1968. A General Purpose, Frequency Multiplex, Telemetry Design for Oceanographic Instrument Systems. Proceedings of the 5th U.S. Navy Symposium on Military Oceanography, pages 309—332.

Chun, C.

1914. Cephalopoda from the "Michael Sars" North Atlantic Deep-Sea Expedition 1910. Report on the

Scientific Results of the "Michael Sars," North

Atlantic Deep-Sea Expedition 1910, 3(1): 1-21,

2 plates.

1915. Die Cephalopoden. II. Teil: Myopsida, Octopoda. Wissenschaftliche Ergebnisse der Deutschen Tiefsee-Expedition, "Valdivia," 18(2): 1-

150, plates 62-95.

Denton, E. J., and J. B. Gilpin-Brown

In press. Buoyancy Mechanisms in Cephalopods. In F.

A. Aldrich, editor, The Biology of the Squid.

New York: John Wiley.

Dollo, L.

1912. Les Cephalopodes adaptes a la Vie Nectique Secondaire et a la Vie Benthique Tertiaire. Zoologische Jahrbucher, 1(15) : 105-140. Jena.

Dorsey, N. E.

1940. Properties of Ordinary Water-Substance. American Chemical Society, Monograph Series No. 81.

673 pages. New York: Reinhold Publishing Corporation.

Ewing, M., and R. A. Davis

1967. Lebensspuren Photographed on the Ocean Floor.

In J. B. Hersey, editor, Deep-Sea Photography,

pages 259-294. Johns Hopkins Oceanographic

Studies (3).

Fleming, R. H., and T. Laevastu

1956. The Influence of Hydrographic Conditions on

the Behavior of Fish. Fisheries Bulletin, F.A.O.,

9(4):181-196.

Forster, G. R.

1967. A New Deep-Sea Ray from the Bay of Biscay.

Journal of the Marine Biological Association of

the United Kingdom, 47(2) :281-286.

Frasetto, R., and J. Northrup

1957. Virgin Islands Bathymetric Survey. Deep-Sea

Research, 4:138-146.

Halberg, P. V., and C. S. Meyers

1966. Mooring Apparatus. United States Patent No.

3,291,092, December 13, 1966.

Hansen, B., and F. J. Madsen

1956. On Two Bathypelagic Holothurians from the

South China Sea, Galatheothuria n.g. aspera

(Theel) and Enypniastes globosa n. sp. Galathea

Report, 2:55-59, 1 plate.

Hantzschel, W.

1962. Trace Fossils and Problematica. Treatise on Invertebrate Paleontology. Part W:W177-W249.

Heezen, B. C, and C. D. Hollister

1971. The Face of the Deep. New York: Oxford University Press. 659 pages.

Heezen, B. C, M. Ewing, and R. J. Menzies

1955. The Influence of Submarine Turbidity Currents

on Abyssal Productivity. Oikos, 6(2) : 1 70-182.

Hersey, J. B.

1967. The Manipulation of Deep-Sea Cameras. In J.

B. Hersey, editor, Deep-Sea Photography, pages

55-67. Johns Hopkins Oceanographic Studies

(3).

Hopkins, R. E., and H. E. Edgerton

1961. Lenses for Underwater Photography. Deep-Sea

Research, 8:312-316.

Hoyle, W. E.

1886. Report on the Cephalopods Collected by H.M.S.

"Challenger" during the Years 1873-76. Report

on the Voyage of the "Challenger." Zoology,

16(44): 1-246, 33 plates.

Ijima, I., and S. Ikeda

1895. Description of Opisthoteuthis depressa n. sp.

Journal of the College of Science, Imperial University, Tokyo, 8(2):323-337.
NUMBER 1 2 1 45

Inman, D. L.

1963. Sediments: Physical Properties and Mechanics of

Sedimentation. Chapter V, 101-151. In F. P.

Shepard, editor, Submarine Geology. 2nd edition.

New York: Harper and Row.

Joubin, L.

1924. Contribution a l'etude des Cephalopodes de l'Atlantique nord. Resultats des Campagnes Scientifi.qv.es du Prince Albert I de Monaco, 67(4): 1-

113, 16 plates.

Kumpf, H. E., and H. A. Randall

1961. Charting the Marine Environments of St. John,

U. S. Virgin Islands. Bulletin of Marine Science

of the Gulf and Caribbean, 11:543-551.

Marshall, N. B.

1960. Swimbladder Structure of Deep-Sea Fishes in Relation to Their Systematics and Biology. "Discovery" Report, 31:1-122.

1965. Systematic and Biological Studies of the Macrourid

Fishes (Anacanthini-Teleostii). Deep-Sea Research, 12:299-322.

Marshall, N. B., and D. W. Bourne

1964. A Photographic Survey of Benthic Fishes in the

Red Sea and Gulf of Aden, with Observations on

Population Density, Diversity and Habits. Bulletin of the Museum of Comparative Zoology, Harvard University, 132(2):223-244.

1967. Deep-Sea Photography in the Study of Fishes.

In J. B. Hersey, editor, Deep-Sea Photography,

pages 251-257. Johns Hopkins Oceanographic

Studies (3).

Massy, A. L.

1916. The Cephalopoda of the Indian Museum. Records of the Indian Museum, 12(16): 185-247.

Menzies, R. J., and G. T. Rowe

1969. The Distribution and Significance of Detrital

Turtle Grass, Thalassia testudinum, on the DeepSea Floor off North Carolina. Internationale

Revue der Gesamten Hydrobiologie, Berlin, 54:

217-222.

Menzies, R. J., J. S. Zaneveld, and R. M. Pratt

1967. Transported Turtle Grars as a Source of Organic

Enrichment of Abyssal Sediments off North Carolina. Deep-Sea Research, 14:111-112.

Meyer, W. T.

1906. Die Anatomie von Opisthoteuthis depressa (Ijima

and Ikeda). Zietschrift fur Wissenschaftliche

Zoologie, 85(2): 183-269, 6 plates.

Mohr, J. L., and S. R. Geiger

1968. Arctic Basin Faunal Precis—Animals Taken

Mainly from Arctic Drifting Stations and their

Significance for Biogeography and Water-Mass

Recognition. In J. E. Sater, coordinator, Arctic

Drifting Stations—A Report on Activities Supported by the Office of Naval Research. The

Arctic Institute of North America.

Moore, D. R.

1963. Turtle Grass in the Deep Sea. Science, 139

(3560)=1234-1235.

Mortensen, Th.

1938. On the Vegetarian Diet of Some Deep-Sea Echinoids. Annotations Zoologique Japan, 17(3,4):

225-228.

Murray, J., and J. Hjort

1912. The Depths of the Ocean. 812 pages. London:

Macmillan and Company.

Okutani, T.

1969. Synopsis of Bathyal and Abyssal Megalo-Invertebrates from Sagami Bay and the South off Boso

Peninsula Trawled by the R/V Soyo-Maru. Bulletin of the Tokai Regional Fisheries Research

Laboratory, 57:1-62.

Ostergren, Hj.

1938. Studien iiber die Seewalzen. Goteborgs Vetenskaps-och Vitterhets-Samhalles Handlingar, 8(4):

1-151, 10 plates.

Patterson, R. B.

1967. A Wide Angle Camera for Photographic Search of

the Ocean Bottom. Proceedings of the Underwater Photo-Optics Seminar, Santa Barbara, October 1966, C-XII-1 to C-XII-8.

Pereyra, W. T.

1965. New Records and Observations on the Flapjack

Devilfish, O pisthoteuthis calif or niana Berry. Pacific Science, 19(4) :427-441.

Perry, R. K., and J. D. Massingill

1971. Seismic and Bathymetric Survey of the Anegada

Trough. Paper 0-91 Presented at the American

Geophysical Union Meeting April 13-16, 1971,

Washington, D.C. Abstract in: E.OS., 52(4)-

1971.

Pollio, J.

1969. Application of Underwater Photogrammetry.

Marine Technology Society Journal, 3:55-72.

Pratt, R. M.

1962. The Ocean Bottom. Science, 138:492-495.

1968. Atlantic Continental Shelf and Slope of the

United States—Physiography and Sediments of

the Deep-Sea Basin. Geological Survey Professional Paper 529-B, 44 pages.

Reinhardt, J. T., and V. Prosch

1846. Om Sciadephorus mulleri (Eschr.). 40 pages, 5

plates. Kjobenhavn: Bianco Lunos.

Robson, G. C.

1924. On the Cephalopods Obtained in South African

Waters by Dr. J. D. F. Gilschrist in 1920-21.

Proceedings of the Zoological Society of London,

3(l):589-686, 2 plates.

1930. Cephalopoda. I. Octopoda. "Discovery" Report, 2:371-402, 2 plates.

1932. Monograph of Recent Cephalopoda. Part II.

The Octopoda (Excluding the Octopodinae). 359

pages. London: British Museum (Natural History).

Rowe, G. T., and R. J. Menzies

1969. Zonation of the Large Benthic Invertebrates in

the Deep Sea off the Carolinas. Deep-Sea Research, 16:531-537.
46 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

Schoener, A., and G. T. Rowe

1970. Pelagic Sargassum and its Presence Among the

Deep-Sea Benthos. Deep-Sea Research, 17:923-

925.

Scott, T.

1910. Notes on Crustacea Found in the Gizzard of a

Deep-Sea Cephalopod. Annals and Magazine of

Natural History, 5(25) : 51-54.

Stephens, W. M.

1966. Life in the Turtle Grass. Sea Frontiers, 12:264-

275.

Thorndike, E. M.

1959. Deep Sea Cameras of the Lamont Geological Observatory. Deep-Sea Research, 5:234-237.

Tomlinson, P. B., and G. A. Vargo

1966. On the Morphology and Anatomy of Turtle

Grass Thalassia testudinum (Hydrocharitaceae).

I. Vegetative Morphology. Bulletin of Marine

Science, 16(4): 748-761.

Townsend, C. H.

1901. Dredging and Other Records of the U.S. Fish

Commission Steamer "Albatross" with Bibliography Relative to the Work of the Vessel. Report of the U.S. Commissioner of Fish and Fisheries for 1900, Section 2, Number 2:387-562.

Verrill, A. E.

1882. The Cephalopods of the Northeastern Coast of

America. Part II. The Smaller Cephajopods Including the "Squids" and the Octopi, with Other

Allied Forms. Transactions of the Connecticut

Academy of Arts and Sciences, 5(6): 259-446, 30

plates.

1885. Third Catalogue of Mollusca. Transactions of

the Connecticut Academy of Arts and Sciences,

6:395-452, 3 plates.

Vinogradov, M. Ye.

1961. Food Sources for the Deep Water Fauna. Speed

of Decomposition of Dead Pteropoda. Dokl

Academii Nauk SSSR, 138:1439-1442. [in Russian]

Voss, G. L.

1967. The Biology and Bathymetric Distribution of

Deep-Sea Cephalopods. Studies in Tropical

Oceanography, 5:511-535.

Welch, B. L.

1963. Aspects of Succession in Shallow Coastal Waters

of the Caribbean. Dissertation Abstracts, 24(5).

Worthington, L. V.

1966. Recent Oceanographic Measurements in the Caribbean Sea. Deep-Sea Research, 13:731-739.

Wiist, Georg, and A. Gordon

1964. Stratifications and Circulation in the AntilleanCaribbean Basins. Part I. Spreading and Mixing

of the \yater Types, with an Oceanographic Atlas.

201 pages. New York: Columbia University

Press.

' U.S. GOVERNMENT PRINTING OFFICE: 1972 • »B4-317/23


Publication in Smithsonian Contributions to Zoology

Manuscripts for serial publications are accepted by the Smithsonian Institution Press, subject to substantive review, only through departments of the various Smithsonian museums. NonSmithsonian authors should address inquiries to the appropriate department. If submission is

invited, the following format requirements of the Press will govern the preparation of copy.

Copy must be typewritten, double-spaced, on one side of standard white bond paper, with

IY2" top and left margins, submitted in ribbon copy with a carbon or duplicate, and accompanied by the original artwork. Duplicate copies of all material, including illustrations, should be

retained by the author. There may be several paragraphs to a page, but each page should begin

with a new paragraph. Number consecutively all pages, including title page, abstract, text, literature cited, legends, and tables. The minimum length is 30 pages, including typescript and illustrations.

The title should be complete and clear for easy indexing by abstracting services. Taxonomic

titles will carry a final line indicating the higher categories to which the taxon is referable:

"(Hymenoptera: Sphecidae)." Include an abstract as an introductory part of the text. Identify

the author on the first page of text with an unnumbered footnote that includes his professional

mailing address. A table of contents is optional. An index, if required, may be supplied by the

author when he returns page proof.

Two headings are used: (1) text heads (boldface in print) for major sections and chapters and (2) paragraph sideheads (caps and small caps in print) for subdivisions. Further

headings may be worked out with the editor.

In taxonomic keys, number only the first item of each couplet; if there is only one couplet,

omit the number. For easy reference, number also the taxa and their corresponding headings

throughout the text; do not incorporate page references in the key.

In synonymy, use the short form (taxon, author, date:page) with a full reference at the

end of the paper under "Literature Cited." Begin each taxon at the left margin with subsequent lines indented about three spaces. Within an entry, use a period-dash (.—) to separate

each reference. Enclose with square brackets any annotation in, or at the end of, the entry.

For references within the text, use the author-date system: "(Jones, 1910)" and "Jones

(1910)." If the reference is expanded, abbreviate the data: "Jones (1910:122, pi. 20: fig. 1)."

Simple tabulations in the text (e.g., columns of data) may carry headings or not, but they

should not contain rules. Formal tables must be submitted as pages separate from the text, and

each table, no matter how large, should be pasted up as a single sheet of copy.

Use the metric system instead of, or in addition to, the English system.

Illustrations (line drawings, maps, photographs, shaded drawings) can be intermixed

throughout the printed text. They will be termed Figures and should be numbered consecutively; however, if a group of figures is treated as a single figure, the components should be

indicated by lowercase italic letters on the illustration, in the legend, and in text references:

"Figure 9b." If illustrations (usually tone photographs) are printed separately from the text as

full pages on a different stock of paper, they will be termed Plates, and individual components

should be lettered (Plate 96) but may be numbered (Plate 9: figure 2). Never combine the

numbering system of text illustrations with that of plate illustrations. Submit all legends on

pages separate from the text and not attached to the artwork. An instruction booklet for the

preparation of illustrations is available from the Press on request.

In the bibliography (usually called "Literature Cited"), spell out book, journal, and

article titles, using initial caps with all words except minor terms such as "and, of, the." For

capitalization of titles in foreign languages, follow the national practice of each language.

Underscore (for italics) book and journal titles. Use the colon-parentheses system for volume,

number, and page citations: "10(2) :5-9." Spell out such words as "figures," "plates," "pages."

For free copies of his own paper, a Smithsonian author should indicate his requirements

on "Form 36" (submitted to the Press with the manuscript). A non-Smithsonian author will

receive 50 free copies; order forms for quantities above this amount with instructions for payment will be supplied when page proof is forwarded.