Freshwater Triclads (Turbellaria)

of North America,

V: The Genus Poly cells

,4k.

ROMAN KENK

SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY • NUMBER 135
SERIAL PUBLICATIONS OF THE 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
SMITHSONIA N CONTRIBUTION S T O ZOOLOGY • NUMBER 135

Freshwater Triclads (Turbellaria)

of North America,

V: The Genus Polycelis

Roman Kenk

SMITHSONIAN INSTITUTION PRESS

City of Washington

1973
ABSTRACT

Kenk, Roman. Freshwater Triclads (Turbellaria) of North America, V: The

Genus Polycelis. Smithsonian Contributions to Zoology, number 135, 15 pages, 9

figures, 1973.—Two species of Polycelis occur in North America, belonging to

two different subgenera, P. (Polycelis) coronata (Girard) and P. (Seidlia) sierrensis, new species. They cannot be distinguished by their external appearance

but only by the anatomy of their reproductive systems. P. coronata is represented

by three subspecies, P. c. coronata with large penis papilla and predominantly

secretory bursal duct; P. c. borealis Kenk with moderately developed penis papilla

and nonsecretory bursal duct; and P. c. brevipenis Kenk with reduced penis

papilla and secretory bursal duct. The anatomical features of the various forms

are described and all known distributional records collected. A comparison is

made of the anatomy of P. sierrensis with that of a closely related Japanese species,

P. auriculata Ijima and Kaburaki.

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

in the Institution's annual report, Smithsonian Year.

COVER DESIGN: Montastrea cavernosa (Linnaeus).

Library of Congress Cataloging in Publication Data

Kenk, Roman, 1898-

Freshwater triclads (Turbellaria) of North America, V: the genus Polycelis.

(Smithsonian contributions to zoology, no. 135)

Bibliography: p.

1. Polycelis. 2. Turbellaria—North America. I. Title. II. Series: Smithsonian Institution.

Smithsonian contributions to zoology, no. 135.

QL1.S54 no. 135 [QL391.T75] 591'.08s [595M23] 72-7410

For sale by the Superintendent of Documents, U.S. Government Printing Office

Washington, D.C. 20402 - Price 45 cents (paper cover)
Contents

Page

Introduction 1

Genus Polycelis Ehrenberg, 1831 2

Subgenus Polycelis 3

Polycelis (P.) coronata coronata (Girard, 1891) 3

Polycelis (P.) coronata borealis Kenk, 1953 7

Polycelis (P.) coronata brevipenis Kenk, 1972 8

Subgenus Seidlia Zabusov, 1911 9

Polycelis (Seidlia) sierrensis, new species 9

Polycelis species 12

Conclusion 14

Literature Cited 14

Freshwater Triclads (Turbellaria)

of North America,

V: The Genus Poly cells

Roman Kenk

Introduction

Information on the occurrence of the genus

Polycelis in North America is rather meager and

scattered in the literature. The first representative

of this genus was discovered in 1877 by Joseph

Leidy in a spring near Fort Bridger, Wyoming.

Leidy himself did not report on this finding, but

apparently handed his notes and collections over to

Charles Girard, who in 1891 published a brief

description of the species, without figures, under

the name of Phagocata coronata, new species. In

1893, Girard expanded his preliminary account and

added illustrations and some of Leidy's field

observations. Hallez (1894:179) recognized the

species as probably belonging to the genus

Polycelis and stated that it might be identical with

the European Polycelis nigra (O. F. Miiller). This

assumption was apparently based on Girard's (1893)

inaccurate plate 5, figure 48, which actually resembles the European species in the contour of the

anterior end and the marginal position of the eye

spots; plate 5, figure 49, of the same animal but

with greater magnification, corresponds better to

the appearance of a preserved specimen of the

American form. Stringer (1918:358) included

Polycelis coronata in her key to American freshwater Turbellaria and reproduced Girard's (1893)

figure 48 and description without having seen additional specimens. She also admitted the possible

identity of the species with P. nigra. Muttkowski

Roman Kenk, Department of Invertebrate Zoology, National

Museum of Natural History, Smithsonian Institution, Washington, D.C. 20560.

(1918:389) reported "Polycelis nigra" from Lake

Mendota, Wisconsin, and in a later paper

(1929:183) from streams in Yellowstone National

Park, Wyoming.

The first modern study of an American Polycelis,

including an analysis of its anatomical features,

was carried out by Hyman (1931). Hyman, who

had been informed by J. H. Powers that a species

of Polycelis occurred in the Black Hills of South

Dakota, visited that area herself and collected

Polycelis in two streams, including sexually mature

specimens. In their external appearance the animals

conformed with Girard's (1893:173) description of

the form from Fort Bridger. Therefore, Hyman

considered them to be identical with Girard's

species, designated them as Polycelis coronata, and

furnished a detailed description of their anatomical

characters. In later papers she indicated the distribution of the species (1951:162) to be "Black

Hills of South Dakota westward to the northwest

Pacific coast," and stated (1953:132) that it "probably occurs generally in the western states at suitable altitudes and temperatures." She (1963:1-2)

mentioned as specific record "the vicinity of Crystal

Springs in the Eastmoreland District of Portland,"

Oregon. In the collections of the Smithsonian Institution are nine lots of specimens (USNM 36070

through 36078) collected in 1937 by D. M. Pike in

Mount Rainier National Park, Washington, and

identified on the labels by Hyman as P. coronata.

Hyman may have seen additional materials from

other localities. It appears, however, that she did

not examine the anatomy of any of these specimens

except the ones from South Dakota.
SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

Polycelis was recorded from the Rocky Mountain

National Park region in Colorado by Kenk (1952).

As the structure of the reproductive system coincided with that of Hyman's (1931) specimens, the

worms were assigned to the species P. coronata.

Kenk also mentioned their occurrence on the

Eastmoreland golf course in Portland, Oregon, and

on Skalkaho Pass, Ravalli County, Montana, where

they had been collected by Betty Locker. Specimens

from these two localities had not been studied

anatomically.

A new species of Polycelis, P. borealis, was described by Kenk (1953:168-173) from about 30

localities in southern Alaska. Six of the lots contained sexually mature animals and were examined

in serial sections.

Beck (1954) reported P. coronata from springs

and streams in seven counties of Utah. He discussed

its general external morphology and natural history

but did not study its anatomical characteristics. It

remained for Braithwaite (1962), one of Beck's

students, to make a more thorough investigation of

the anatomy of the Polycelis from Utah, on which

he reported in his unpublished Master of Science

thesis. Examination of the reproductive system of

specimens from one of Beck's localities (on Mt.

Timpanogos, Utah County) revealed certain differences from the published anatomical accounts of

the North American representatives of the genus.

Braithwaite made a careful comparison of the

copulatory complex of his specimens with the

available descriptions of P. coronata from South

Dakota by Hyman (1931) and of P. borealis from

Alaska by Kenk (1953). In the absence of an

adequate description of worms from Girard's typelocality, Fort Bridger, he could not settle the question whether the name P. coronata should be

applied to the species from Utah or to that of North

Dakota, or if the Utah form represented a new

taxon.

Additional finds of Polycelis species were reported

by Holmquist (1967:463) from southern Alaska, by

Kennedy (1967:8) from Mono County, California,

and by Ball and Fernando (1968) from Jasper

National Park in Alberta, Canada. Carpenter

(1969:280) recorded the presence of P. coronata in

several springs and streams in Logan Canyon,

Cache County, Utah. Two of Carpenter's localities

were mentioned also in one of my recent papers

(Kenk, 1970:22) in addition to Polycelis species of

Nevada County, California.

On two field trips in 1967 and 1970, I succeeded

in collecting Polycelis in two springs near Fort

Bridger, Uinta County, Wyoming, one of which

may well have been the spring in which Leidy had

discovered Girard's species in 1877. The animals

proved to be specifically identical with those from

Utah. In a key to the North American freshwater

triclads I (1972) attempted to differentiate between

the various morphologically distinct units, combining the described forms under one species, P.

coronata, with the nominate subspecies P. c.

coronata from Fort Bridger and Utah, the subspecies P.c. borealis from Alaska, and introducing

a new subspecies, P.c. brevipenis, for the form from

South Dakota and Colorado. In addition I studied

a Polycelis from the Sierra Nevada which proved to

be specifically and subgenerically different from P.

coronata.

ACKNOWLEDGMENTS.—This study was in part

supported by National Science Foundation Grant

GB-6016 to the George Washington University.

Thanks are due also to many individuals who have

served as guides or collaborators in the field work

or have furnished specimens or valuable information: Reed Bluemel, Dr. Lee F. Braithwaite

(Brigham Young University), Dr. C. J. D. Brown,

(Montana State University), R. Andrew Cameron,

Jerry H. Carpenter, Frank P. Crawley, Robert

A. Dalton (Bear Lake Biological Station, Utah),

Jack L. Dean (U. S. Fish and Wildlife Service,

Yellowstone National Park), Peter N. D'Eliscu and

Dr. M. H. Gunnell (Utah State University), Dr.

John C. Harshbarger (Smithsonian Institution),

Vernon M. Hawthorne (Sagehen Creek Biological

Station, California), Timothy F. Hicks, Dr. Vida

C. Kenk (San Jose State College), John Matrisciano,

Dr. G. Wayne Minshall (Idaho State University), Robert E. Olson, Melvin B. Taylor, Michael

W. Tunicliffe and Richard Whitten (Powell Laboratories, Gladstone, Oregon).

Genus Polycelis Ehrenberg, 1831

The genus Polycelis was established by Ehrenberg

(1831:2) for turbellarians with branched intestine

("Dendrocoela") which possess numerous eyes

arranged in a row at the anterior end. Originally

the genus contained two European freshwater
NUMBER 135

triclads, Miiller's (1774:54) Fasciola or Planaria

nigra, and P. brunnea. Later authors enlarged the

genus by adding to it representatives of terricolous triclads and of polyclads which conformed

to Ehrenberg's definition. Stimpson (1857:24) and

Diesing (1862:508) again restricted Polycelis to

freshwater triclads. At present the genus is placed

in the family Planariidae of the Tricladida Paludicola which is characterized by having the internal

muscle zone of the pharynx composed of two distinct layers of muscle fibers, a circular layer adjoining the epithelium and a longitudinal layer. The

present definition of Polycelis is as follows: Planariidae in which the oviducts, without embracing the

bursa stalk, unite to an unpaired duct which opens

into the genital atrium; zone of testes extending to

the level of the pharynx; male atrium without

radial muscle plates; eyes numerous. Type-species,

Fasciola nigra O. F. Muller (Kenk, 1930:294).

In 1930, I proposed to divide the genus Polycelis

into two subgenera, Polycelis, sensu stricto, without

adenodactyls (or muscular gland organs) and Ijimia

Bergendal (type-species, Polycelis tenuis Ijima)

with solid adenodactyls attached to the genital

atrium (Kenk, 1930:294). Later investigations,

however, particularly those of Lepori (1955), show

that adenodactyls may be either present or absent

in P. tenuis. There are also indications that P.

tenuis and P. nigra may interbreed in the laboratory although this question is not finally settled

(Benazzi, 1963). In any case, the subgenus Ijimia

as based on the presence of adenodactyls can no

longer be retained.

A group of species of Polycelis of the Asian continent and the Japanese islands shows an extraordinary thickness of the muscle coat surrounding

the male atrium. I reintroduced Zabusov's (1911,

appendix, page 7) subgeneric name Seidlia for this

group (Kenk, 1953:172), with the type-species

SoroceJis sabussowi Seidl (1911:36). Both subgenera,

Polycelis and Seidlia, are represented in North

America.

Subgenus Polycelis

Male atrium without excessively developed

muscle coat.

Polycelis (P.) coronata coronata (Girard, 1891)

FIGURES 1, 2, 3, 6A, B

Phagocata coronata Girard, 1891:80.

Polycelis coronata.-Hallez, 1894:172, 179.

EXTERNAL FEATURES.—Adult specimens are 12—20

mm long and 1.5-2.5 mm wide when gliding

quietly. The anterior end is truncate, with gently

convex frontal margin and a pair of rather prominent auricles projecting laterally (Figure 1). These

auricles, when seen from above, appear triangular,

with bluntly pointed or rounded tips. During locomotion they are raised above the substrate. Behind the auricles the head narrows insignificantly,

forming a "neck." Behind the neck, the lateral

l m m

FIGURE 1.—Polycelis coronata coronata, outline sketch of

living animal.

margins of the body gradually diverge and soon

reach the maximum width. In the last third or

fourth the margins converge again to meet in the

rounded posterior end.

The color of the dorsal side is a variable shade

of brown, from light brown to almost black, appearing somewhat mottled under magnification,

with lighter areas above the pharynx and copulatory complex. The ventral side is also pigmented

but somewhat lighter. The eyes (Figure 6A, B)

are numerous and are arranged in a band, more

than one row wide, extending along the frontal

margin, the base of the auricles, and about onefifth to one-fourth the prepharyngeal lateral margin

where they taper to a single row. The band may

narrow to some extent in the frontal midline or

at the base of the auricles but this is not the case

in all individuals. The auricular projections themselves are free of eye spots. The number of the

eyes varies and increases in the course of the growth

of the animal. Beck (1954:81) counted from 28

to 70 eyes on any one side of his specimens. The

eyes are seen as small, reniform, black spots, lacking the white, pigment-free areas usually associated with the eyes of two-eyed pigmented planarians.

The locomotion of the species is by gliding only;

no "crawling" movements have been observed. In

laboratory cultures the worms are frequently seen

gliding on the underside of the surface film in the

aquarium, a tendency that is mentioned also by
SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

Braithwaite (1962:22) who observed them in nature in stagnant pools during the night and early

morning, while in daytime they were found on the

undersurfaces of submerged objects.

ANATOMY.—The digestive system shows no peculiarities. On account of the pigmentation of the

body, the branching of the intestine can rarely be

analyzed in the living animal. In preserved and

cleared specimens I counted 5-8 lateral branches

on each side of the anterior intestinal ramus and

14—16 branches on each posterior ramus. The

pharynx is rather large, its length amounting to

about one-fourth the body length in adult specimens. The arrangement of the pharyngeal muscles

is of the planariid type, the fibers of the internal

muscle zone forming two separate layers, a circular

and a longitudinal one.

REPRODUCTIVE SYSTEM.—The densely clustered,

large testes are situated in a pair of short bands

occupying chiefly the areas between the anterior

intestinal ramus and the ventral nerve cord on

either side and extending from behind the first or

0-5 mm

second lateral branch of the intestine to the insertion of the pharynx. Their position is ventral, although a few individual follicles may be pushed

toward the dorsal side. The thin anterior sperm

ducts or vasa deferentia run along the medial sides

of the ventral nerve cords, close to the ventral integumental muscle layers. They connect with the

individual testes by means of short branches, the

vasa efferentia or sperm ductules. In the region of

the pharynx each vas deferens expands to form the

tortuous false seminal vesicle (or spermiductal vesicle), filled with sperm, which proceeds backward

toward the copulatory complex.

The ovaries are located at the level of the first

lateral intestinal branches, on the medial side of

each ventral nerve trunk. They have no typical

parovaria.

The copulatory apparatus (Figure 2) occupies

the anterior half of the postpharyngeal region.

The genital aperture or gonopore (gp) leads into

an undivided genital atrium. The penis consists

of a rounded, muscular bulb (bp) and a conical

bg ode bd

ph m b vd bp pi gp

FIGURE 2.—Polycelis coronata coronata from Fort Bridger, Wyoming, copulatory apparatus in

sagittal section. [Abbreviations for this and following figures: a—genital atrium; ac—common

genital atrium; am —male atrium; b=copulatory bursa; bd=bursa duct; bg=cyanophilic

gland ducts; bp=penis bulb; cy=cyanophilic glands; de=ejaculatory duct; eg=eosinophilic

gland ducts; gp=gonopore; i:= intestine; m=mouth; ma—muscle coat of atrium; ode =:common

oviduct; pa ;= a trial papilla; ph=pharynx; pi—penis lumen; pp—penis papilla; sg—shell glands;

vd=vas deferens; vs—seminal vesicle.]
NUMBER 135

papilla. There is wide variation in the size relationships between the bulb and the papilla, due in

part to the state of muscular contraction at the

moment of killing, in part to the phase of sexual

maturity, and possibly to characteristics of local

populations. In general, the penial papilla is as

large as, or larger than, the bulb, differentiating

the subspecies P.c. coronata from P.c. brevipenis.

The penial lumen (pi) is rather voluminous, forming in the bulb a wide expansion of irregular outline which usually narrows posteriorly and opens

at the tip of the papilla. There is no sharp demarcation between the anterior widened part

(seminal vesicle) and the posterior section (which

corresponds to an ejaculatory duct). The musculature of the penis bulb consists of concentrically

arranged layers of muscle fibers. The papilla has

a circular muscle layer below the external epithelium, followed by longitudinal fibers traversing the

parenchyma of the papilla. The epithelial lining

of the expanded bulbar lumen consists of tall cylindrical, often club-shaped, secretory cells sometimes

extending into the cavity as villus-like projections.

The epithelium of the ejaculatory duct is cuboidal

and nucleate, that of the outside of the papilla

flattened and, at least in fully mature specimens, in

part infranucleate. The two vasa deferentia enter

the penis bulb anteroventrally and open into the

penial lumen separately, often in an asymmetrical

fashion, one more anterior or more dorsal than

the other. To what extent this asymmetry h a

result of muscular contraction or due to the asymmetry of the canal of the copulatory bursa is difficult to decide. At full sexual maturity the penis

is supplied with copious gland ducts entering the

penial bulb from the surrounding parenchyma.

These ducts, filled with a granular, usually slightly

eosinophilic, secretion, traverse the bulb and the

papilla and open into the penial lumen. In animals from northern Montana and from Mount

Rainier National Park (Figure 3), the secretions

contained in the ducts were tinctorially differentiated into cyanophilic secretions (eg) emptying into

the seminal vesicle and eosinophilic secretions (eg)

connecting with the posterior part of the lumen.

It was not possible to ascertain whether this differentiation corresponds to a particular phase in

the developmental cycle of the reproductive system

or is a peculiarity of the local populations.

The two oviducts or ovovitelline ducts proceed

from the ovaries along the dorsal sides of the ventral nerve cords. In the region of the copulatory

complex they leave the nerve cords, turn upward

and medially, and unite in the space above the

male atrium to form a common oviduct. The end

parts of the paired oviducts and the unpaired common oviduct are equipped with strongly eosinophilic glands, the so-called shell glands (Figure 3,

sg). The common oviduct opens into the end part

of the genital atrium from the dorsal side. The

copulatory bursa (b) is a voluminous, often very

lobate sac situated between the pharyngeal pouch

0.5mm

FIGURE i.—Polycelis coronata coronata from Yellow Creek, Lake County, Montana; copulatory

apparatus in sagittal section. [See Figure 2 for abbreviations.]
SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

and the penial bulb in the midline of the body.

Its outlet or stalk (bd) is displaced from the median, usually to the left but in some individuals

to the right side of the penis. Histologically the

stalk is divided into sections, a wider anterior section lined with a continuation of the tall secretory

epithelium characteristic of the bursal sac (Figure

2, bg), and a narrower posterior section with nonglandular lining and a thick muscular coat consisting of circular and longitudinal fibers. The

proportion between the two sections is somewhat

variable, in specimens from the type-locality (Fort

Bridger) the glandular section is about as long as

the muscular one. The bursal stalk opens into the

genital atrium close to the gonopore.

ECOLOGY AND DISTRIBUTION.—Polycelis coronata

corona ta inhabits springs and cold creeks in the

western parts of the United States. Beck (1954:81)

indicates that in Utah the species is confined to

habitats of low water temperature, not exceeding

10°C, a statement which was confirmed by Braithwaite (1962:21) and which is valid also for other

localities of its geographic range. The species is,

therefore, found generally at high altitudes. No

intensive studies concerning other ecological requirements (ionic composition of the water, food

supply, etc.) have been made. When the animals

are collected in the field, the great majority of

the specimens are found to be immature. As the

identification of the species and subspecies is possible only by the analysis of the reproductive system, only localities at which sexually mature

individuals have been taken have been included in

the following listing.

MONTANA. LAKE COUNTY: (1) Tributary of Flathead

Lake, crossing State Road 35 on east side of lake, 12 road

miles north of junction with U. S. Highway 93; 3 September

1967, water clear, fast, 8.7°C, pH 7.9; many specimens of

various sizes (some with short postpharyngeal parts indicating

recent fission), one mature, under stones. (2) Yellow Bay

Creek, about 10 yards from the shore of Flathead Lake;

several specimens, some mature, collected in August and

September 1969 by Frank P. Crawley and shipped to me

alive. (Besides this species, one specimen of Dendrocoelopsis

xmginata Hyman).

NEW MEXICO. SANTA FE COUNTY: Stream on west slope

of Sangre de Cristo Mountain, crossing State Road 475, 2.5

road miles above the north boundary of Hyde State Park, at

an altitude of about 9000 feet; 17 July 1968, water clear, fast,

8.8"C, pH 72; many specimens of various sizes, among them

some adults, under stones.

UTAH. CACHE COUNTY: Spring Hollow Stream, off

U. S. Highway 89, 5 road miles east of Utah State University

in Logan; samples collected at various occasions by myself

(September 1967), Jerry H. Carpenter (March 1968) and

Prof. M. H. Gunnell (May 1969); besides Polycelis, Phagocata

crenophila occurs here. RICH COUNTY: Willow Springs, located 4 air miles west of Garden City; 27 September 1967, clear,

fast water; many specimens, some mature, under stones. UTAH

COUNTY: North Fork of Provo Canyon, on Mt. Timpanogos,

in headwaters at Aspen Grove, off State Road 80; 26 September 1967, water clear, 6.7°C, pH 7.7, fast current; numerous

Polycelis, many mature, under stones (this is the locality

where Braithwaite collected his sexual specimens, see Braithwaite, 1962:24).

WYOMING. UINTA COUNTY: (1) Scoop Shovel Spring,

located about 4 miles west of entrance to Fort Bridger, perhaps % mile north of Interstate Road 80 (water from this

spring had been used by the inhabitants of the area for

domestic purposes for many years; it is possible that this is

the type-locality where Leidy collected his specimens in

1877); 30 September 1967, little water flow; many specimens,

3 mature, under stones and pieces of wood. 7 June 1970,

water clear, 7.0°C, moderate current; under stones very

many worms of various sizes, about one-third of them

showing sexual structures, at least two with signs of recent

fission (regenerating hind ends). (2) Spring about 6 miles

west of Fort Bridger, on property of Reed Bluemel (who

kindly took me to this spring), 1.8 miles west of Union Road

exit of Interstate Highway 80 and % mile south of the

highway; 30 September 1967, clear, cold water, under stones

6 Polycelis, one of them mature.

LIFE CYCLE.—Field observations are too scarce to

permit definite conclusions as to the seasonal behavior and reproductive activity of the species. Sexually mature specimens were taken in different

places in March, May, June, July, August, and

September, always together with immature, presumably younger individuals. Braithwaite (1962:

21) found mature worms from June through November; he could not examine his locality during

the winter months because of the snow cover. It

is quite possible that the worms may reproduce

sexually the year round in springs with little seasonal temperature fluctuations, but only seasonally

(in winter?) in habitats in which the temperature

is not constant. Egg capsules have not been observed; presumably they are spherical or ellipsoidal

and unstalked.

Asexual reproduction by fission, as revealed by

the presence of individuals with regenerating head

or tail ends, has been observed occasionally in the

field collections. Postfission specimens may be seen

in a population at the same time as sexually mature specimens.

In the laboratory, Polycelis coronata may be

maintained in cold-water cultures for extended

periods of time. Five immature specimens, col-
NUMBER 1S5

lected 30 September 1967 near Fort Bridger, Wyoming, were kept in spring water at 14°C and fed

alternatingly beef liver and Tubifex, which were

freely taken. They developed sexual structures by

December, but never laid cocoons nor underwent

typical fission (only occasional divisions after mechanical injuries). The culture was concluded in

May 1969.

TAXONOMIC POSITION.—The nearest relatives of

Polycelis coronata are found in Asia. P. tibetica

Hyman, from Kashmir and Indian Tibet, seems to

have a copulatory complex similar to that of the

American species, including the division of the

bursa stalk into a wider secretory anterior and a

narrower nonglandular posterior section (Hyman,

1934:9, pi. 1: fig. 7). Polycelis koslowi (Zabusov,

1911:345), also from Tibet, resembles P. coronata

in its external and anatomical features. In P.

eburnea (Muth, 1912) from the Aral Sea area, the

reproductive system conforms with that of the

American species but the arrangement of the eyes

appears to be different. No detailed comparison

of these species with the American form can be

made at present. Should futiire investigations show

that P. coronata is identical with any of the Asian

species, it would nevertheless keep its name since

its establishment predates the descriptions of the

three other forms.

Polycelis (P.) coronata borealis Kenk, 1953

FIGURE 4

Polycelis borealis Kenk, 1953:168.

Polycelis coronata borealis.—Kenk, 1972:27.

HOLOTYPE.—Springs on road from Palmer to Willow, Alaska; series of sagittal sections, USNM

22333.

The subspecies P.c. borealis was originally described from Alaska as a separate species at a time

when the anatomy of the typical Polycelis coronata

had not yet been studied. The only American

Polycelis with which it could be compared was the

form from South Dakota and Colorado. Between

this and the Alaskan worms there were some differences which seemed to justify the establishment

of a new species. With the rediscovery of Girard's

P. coronata, however, these differences have in part

been bridged over, and it appears now to be more

practicable to unite the three forms as subspecies

under the same specific name, P. coronata.

CHARACTERISTICS OF THE SUBSPECIES.—P.C. borealis cannot be differentiated from the nominate

subspecies in life. A description of P. borealis has

been presented by Kenk (1953:168-173) and need

not to be repeated here. The account of the external features given for the subspecies P.c. coronata (p. 3) may be extended also to the present

subspecies.

P.c. borealis differs from P.c. coronata mainly in

some details of the anatomy of the reproductive

system (Figure 4), specifically in the structure of

the outlet or stalk of the copulatory bursa. In

P.c. coronata this stalk is divided into two sections,

an anterior wider section lined with a secretory

epithelium identical with that of the lining of the

bursa, and a posterior section with nonglandular

lining and a thick coat of muscle fibers. The subspecies P.c. borealis lacks this differentiation of

the bursal duct, and the entire canal is nonglandular and muscular. It is situated either on the left

or on the right side of the penis.

ECOLOGY AND DISTRIBUTION.—Polycelis coronata

borealis lives in cold streams and springs in the

northwestern parts of the North American continent. Sexually mature individuals were collected

in the following localities:

ALASKA (see Kenk, 1953:173). (1) Clear, fast mountain

stream crossing Mount McKinley Park road, 5.5 miles from

railroad station, 5 August 1950. (2) and (3) Streams on road

from Palmer to Willow, 11.9 and 192 miles from Palmer,

9 August 1950. (4) Clear springs on road from Palmer to

Willow, 20.1 miles from Palmer (type-locality of subspecies),

9 August 1950. (5) Stream on road from Anchorage to Potter,

10.6 road miles from Anchorage city limits, 12 August 1950.

bd ode

FIGURE A.—Polycelis coronata borealis from type-locality on

road from Palmer to Willow, Alaska; copulatory apparatus

in sagittal section (after Kenk, 1953), X 61. [See Figure 2

for abbreviations.]
8 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

(6) Stream on Glenn Highway, 43.5 miles from Anchorage,

13 August 1950.

IDAHO. BINCHAM COUNTY: Headwaters of Spring Creek,

situated in Fort Hall Bottoms, Fort Hall Indian Reservation,

near Ferry Butte, northwest of Pocatello; springs on marshy

ground; 3 June 1970, water clear, with moderate current,

10.6°C; under stones about 30 specimens collected by Dr. G.

Wayne Minshall and R. Kenk, among them one mature

individual.

WYOMING. YELLOWSTONE NATIONAL PARK: (1) Tributary

of Obsidian Creek, at Moose Exhibit, 10.8 miles south of

Mammoth Springs Junction; 18 June 1963, water clear, fast,

9.0° C; several specimens collected, two of them mature. (2)

Stream at south end of Swan Lake Flat, east of road between

Norris and Mammoth Springs junctions; 18 June 1963, water

clear, with moderate current, 2O.5°C; many specimens, some

of them very large (largest 25 mm long), two mature. (3)

Cascade Creek, crossing road 0.4 mile west of Canyon Village

Junction; 7 September 1967, water clear, fast, 12.1 °C, pH

8.1; under stones 7 immature specimens, some with signs of

fission (regenerating tails); 28 September 1967 in the same

locality 6 immature specimens taken under stones and placed

in culture (one matured). (4) Yellowstone Lake; 4 September

1970, 6 specimens collected by Jack L. Dean off the south end

of Stevenson Island on liver bait submerged the preceeding

day at about 200 feet (61 m) depth, one of them mature.

LIFE CYCLE.—Reproduction of the subspecies is

both sexual and asexual, by fission. Sexually mature specimens were collected in different localities

in June, August, and September, but always fewer

than the more numerous immature worms. This

suggests that the height of the breeding season may

not be in the summer months but rather during

the cold season.

Four immature specimens which had been collected in Yellowstone National Park in September

1967 were placed in a laboratory culture kept at a

temperature of 14°C. They were given beef liver

and Tubifex, alternatingly, as food and underwent

fission repeatedly. In September 1968 some of the

worms were transferred to a culture maintained at

a lower temperature (fluctuating between 1.4° and

8.4°C) in which they continued fissioning. In July

1969, when the culture was concluded, one of the

seven specimens, 14 mm long, had developed reproductive organs while the others were smaller

and showed various stages of postfission conditions

(short tails and new heads).

Poly celts (P.) coronata brevipenis Kenk, 1972

FIGURE 5

Polycelis corona/a.-Hyman, 1931:124-135.-Kenk, 1952:194-

198.

Polycelis coronata brevipenis Kenk, 1972:27.

vs vd

FIGURE 5.—Polycelis coronata brevipenis from type-locality,

Glenhaven, Larimer County, Colorado; copulatory apparatus in sagittal section (after Kenk, 1952), X 60- [See

Figure 2 for abbreviations.]

HOLOTYPE.—North Fork of Thompson River, 1

mile below Glenhaven, Larimer County, Colorado;

series of sagittal sections, USNM 23679.

The subspecies P.c. brevipenis was first described

from South Dakota by Hyman (1931) who assumed

that it was identical with Girard's Phagocata coronata from Wyoming, which was known only by its

external appearance. Hyman's description was

later supplemented by Kenk (1952) who collected

the same form in Colorado. Braithwaite (1962),

while studying the anatomy of a Polycelis from

Utah, discovered certain differences between his

worms and Hyman's account of the reproductive

system of the South Dakota form. As he had no

comparative material from Girard's type-locality,

he refrained from naming the local species from

Utah and pointed out that the problem of the

taxonomic status of the North American Polycelis

was not yet settled. Kenk (19.72:27), upon examining specimens from Fort Bridger, Wyoming, recognized their identity with the form from Utah and

considered the animals from South Dakota and

Colorado to be sufficiently different from the worms

of Wyoming to justify the establishment of a new

subspecies, P.c. brevipenis.

CHARACTERISTICS OF THE SUBSPECIES.—In life P.c.

brevipenis is indistinguishable from the nominate

subspecies (p. 3; see also Hyman, 1931:126-127;

Kenk, 1952:194-195). It differs from the subspecies

P.c. coronata in the shape and structure of the male

copulatory organ (Figure 5). The penis bulb is

elongated, very muscular, and much larger than

the short and rather broad penis papilla. The

penis lumen is likewise elongated, its bulbar section (seminal vesicle) is lined with a cuboidal,
NUMBER 1S5

nonglandular epithelium. The two vasa deferentia

enter the seminal vesicle from the sides, often

asymmetrically. Many gland ducts containing a

slightly eosinophilic secretion penetrate the muscular layers of the penis bulb and empty into the

seminal vesicle. The bursal stalk shows the same

division into an anterior glandular and a posterior

muscular section as in the case of the nominal

subspecies.

ECOLOGY AND DISTRIBUTION.—P.C. brevipenis, like

the two other subspecies of P. coronata, is an inhabitant of cold streams and mountain lakes and

has, so far, been recorded only from South Dakota

and Colorado, but it is probably more widely distributed in the mountainous regions of the western

states. The following localities yielded sexually

mature specimens:

COLORADO (cf. Kenk, 1952:196). LARIMER COUNTY: Localities in Rocky Mountain National Park: (1) Poudre Lake,

(2) Thompson River in Moraine Park, (3) Chiquita Creek

on Fall River Road, and (4) Glacier Creek (tributary of

Thompson River), 24-27 September 1951. (5) North Fork of

Thompson River, 1 mile below Glenhaven (type-locality of

the subspecies), 28 September 1951.

SOUTH DAKOTA. Stream near Dead wood (Lawrence

County?), in the Black Hills, 30 August 1929 (see Hyman,

1931:180).

LIFE CYCLE.—Hyman stated that many of the

worms collected in August in the stream near Deadwood were sexually mature, that no cocoons were

found in the field, and that there were no indications of the occurrence of fission. Kenk (1952:1%)

reported that among 39 specimens taken in Glacier

Creek in September, 17 were asexual, showing no

signs of reproduction, 20 showed evidence of recent

A B

fission, and only 2 were sexually mature. In other

localities, the great majority of the collected animals were also asexual. These data are too meager

to permit any conclusions concerning the seasonal

distribution of the reproductive activity.

Subgenus Seidlia Zabusov, 1911

Male atrium surrounded by a very thick muscle

coat.

PolyceUs (Seidlia) sierrensis, new species

FIGURE 6C, 7, 8

HOLOTYPE.—Deep Creek, Placer County, California; series of sagittal sections, USNM 46053.

EXTERNAL FEATURES.—Mature animals are up to

22 mm long and about 2 mm wide. Head truncate,

with slightly bulging frontal margin and a pair

of bluntly pointed auricles extending from the lateral edges anterolaterally (Figure 7). After a slight

narrowing or neck behind the auricles, the body

margins first diverge, then run parallel throughout

the greater part of the body length. Behind the

copulatory apparatus the body narrows again and

forms a pointed to rounded posterior end.

The dorsal side is dark brown; the areas above

the pharynx and the copulatory complex are somewhat lighter. Ventral side grayish brown, with

white spots indicating the sites of the mouth and

the gonopore. The numerous eyes (Figure 6c)

form a band along the margin of the head and

the anterior part of the prepharyngeal region. This

band may be interrupted at the base of the auricles.

•I

FIGURE 6.—Anterior ends of preserved animals, showing arrangement of eyes: A, Polycelis coronata

coronata from Fort Bridger, Wyoming, x 30; B, P. c. coronata from Provo Canyon, Utah, X 17;

c, P. sierrensis from Nevada County, California, x 17; D, P. auriculata from Hidaka, Hokkaido,

Japan, x 17.
10 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

FIGURE 7.—Polycelis sierrensis, outline sketch of living animal.

On the head it is more than one row wide, but it

narrows posteriorly to a single row. The number

of the eyes varies within wide limits. There are

fewer eyes in smaller (younger?) individuals than

in larger ones. In adult specimens 36 to 108 eyes

were counted on either side of the head, not necessarily symmetrically arranged.

The pharynx is rather long, about one-fourth

the length of the body. Its insertion or root is at,

or somewhat anterior to, the middle of the body.

The copulatory complex occupies two-thirds of the

postpharyngeal region.

As seen from this description, P. sierrensis cannot be distinguished from P. coronata in life with

certainty. In P. sierrensis, the band of eyes may be

narrower and slightly more marginal than in P.

coronata, but this is not the case in all individuals.

REPRODUCTIVE SYSTEM.—The testes are ventral

and are arranged in a pair of rather short bands

in the posterior half of the prepharyngeal region,

situated on either side of the anterior intestinal

ramus and extending laterally as far as the ventral

nerve cords. The ovaries are located at the level of

the first or second lateral intestinal branches, somewhat anterior to the testicular bands.

The copulatory complex (Figure 8) shows the

genital atrium divided into a small posterior common atrium (ac) and a larger anterior male atrium

(am), the two subdivisions communicating by

means of a narrow canal which, in fully mature

animals, runs in the axis of a conical papilla (pa)

projecting into the male atrium; this atrial papilla

or diaphragm is developed only at full maturity.

The common atrium connects with the genital

aperture (gp), the outlet (bd) of the copulatory

bursa (b), and the common oviduct (ode). The

male atrium, which is lined with a cuboidal epithelium, is surrounded by a very thick, massive

muscular layer (ma) consisting chiefly of circular

fibers interspersed with less numerous longitudinal

fibers. The penis has a rounded bulb and a conical

papilla (pp). The bulb contains a large cavity

(pi) with villus-like processes projecting from the

wall. Posteriorly, toward the penis papilla, the

cavity narrows and its wall becomes smooth, forming what may be compared to an ejaculatory duct.

The cavity opens at the tip of the penis papilla.

The two vasa deferentia, which at the sides of

the pharynx have enlarged to spermiductal vesicles,

turn upward and medially at the level of the penis

0.5 mm

vd p| pp ma am pa gp

FIGURE 8.—Polycelis sierrensis from type-locality, Deep Creek, south of Truckee, California;

copulatory apparatus in sagital section. [See Figure 2 for abbreviations.]

ac ode bd
NUMBER 135 11

bulb, approach the bulb, enter it from the sides,

and open separately into the bulbar lumen. The

lumen also receives many ducts originating from

unicellular glands located in the parenchyma surrounding the penis. The two oviducts unite in the

space above the common genital atrium, forming

a short common oviduct (ode) which empties into

the common atrium from the dorsal side. The end

parts of the paired oviducts and the common oviduct receive many outlets of eosinophilic glands.

The copulatory bursa (b) is a large, lobate sac

without prominent lateral extensions. Its duct

(bd) runs posteriorly, normally on the right side

of the midline (only exceptionally above the penis).

The secretory epithelium lining the bursa extends

some distance into the anterior part of the bursal

duct.

ECOLOGY AND DISTRIBUTION.— Polycelis sierrensis

was collected in cold springs and streams in the

region of the Sierra Nevada of California and

Nevada. The few observations on the physicochemical conditions of its habitats do not permit

definitive conclusions concerning the ecological requirements of the species. The temperature range

of the water was between 6.2° and 16.5°C, with an

average of 9.2°C (12 measurements); the pH between 6.1 and 7.7, average 7.0 (11 measurements);

and the oxygen content between 7 and 10 parts per

million, average 9 ppm (4 measurements). It must

be pointed out, however, that these observations

were made in the warmer seasons of the year, from

late May to September, and that no data are available on the seasonal fluctuations of these parameters. Other factors which may influence the

occurrence of the species, such as the chemical composition of the water, the available food supply,

etc., have not been studied. Sexually mature individuals were taken in the following localities:

CALIFORNIA. MARIPOSA COUNTY: Fern Spring, in Yosemite National Park, on road connecting State Roads 140 and

41. Limnocrene with considerable water flow and several

seepage springs above it; 3 July 1967, water temperature

6.4° and 6.8°C, pH 6.1 and 6.2; several specimens under

stones, one of them mature, one with regenerating head.

5 July 1968, temperature 7.3°C, 17 specimens of various sizes,

2 mature. NEVADA COUNTY: Spring near Sagehen Creek

Biological Station, tributary of Sagehen Creek, furnishing

water to the station. Situated about 2 miles west of State

Road 89, north of Truckee; 23 September 1967, water clear,

fast, temperature 6.3 °C, pH 7.5, under stones 3 specimens;

10 July 1968, 6J>°C, pH 7.5, oxygen 10 ppm, many specimens

under stones, some mature; 28 and 29 May 1970, temperature

6.3°C, pH 7.5, oxygen 9 ppm, about 50 Polycelis under stones

and on bait (beef liver) exposed over night, some mature.

Besides this species, less numerous Phagocata crenophila

Carpenter. PLACER COUNTY: (1) McKinney Creek near its

mouth on the west shore of Lake Tahoe, close to the £1

Dorado County line; 21 June 1967, clear, fast water, 9.0°C,

pH 7.1, about 10 specimens under stones, 2 mature. (2)

Tahoe City, overflow of spring furnishing water to the local

California Fish and Game facility, on State Road 28, 1.7

road miles northeast of junction with State Road 89; 23

September 1967, water clear, fast, temperature 6.7°C, pH 6.8,

6 immature Polycelis under stones; 10 July 1968, 6.2°C pH

6.6, oxygen 10 ppm, several Polycelis under stones, 2 of them

mature; 28 and 29 May 1970, 10.0°C, pH 7.0, oxygen 7 ppm,

many mature and immature specimens under stones and on

liver bait. Besides Polycelis, Phagocata crenophila occurs here.

(3) Deep Creek, at crossing of State Road 89 south of Truckee

(type-locality of Polycelis sierrensis); 23 September 1967,

water clear, fast current, temperature 10.6°C, pH 7.7, 4 immature post-fission specimens under stones; 10 July 1968, 3

specimens, 2 of them mature.

NEVADA. WASHOE COUNTY: Marlette Creek, along State

Road 28, about y2 mile north of Ormsby County line; 11

July 1968, water clear, fast, 16.5°C, pH 7.4, 2 specimens

under stones, 1 mature.

LIFE CYCLE.—The few sexually mature specimens

collected from May to September allow no conclusions regarding the breeding season of the species. Generally they were taken together with more

numerous asexual specimens some of which in individual cases showed signs of active fission. No

egg capsules were seen in the field. No attempt was

made to culture the species in the laboratory. Presumably it could be maintained in cold-water cultures, with liver as food, since it has been

successfully attracted by beef liver used as bait.

TAXONOMIC POSITION.—P. sierrensis is rather

closely related to a Japanese species, P. auriculata

Ijima and Kaburaki (1916). Through the courtesy

of Dr. Masaharu Kawakatsu of Fuji Women's College in Sapporo, Japan, who kindly sent me several

living specimens of P. auriculata from Hidaka,

Hokkaido, I was able to compare the two species in

greater detail. Externally P. auriculata is similar to

P. sierrensis by its general shape, size, and pigmentation. There is a difference in the arrangement of the eyes which in P. auriculata form a

wider, horseshoe-shaped band which does not reach

as far backward as in P. sierrensis (Figure 6C,D).

In the copulatory apparatus the differences mainly

concern the atrial papilla or diaphragm and the

shape of the copulatory bursa (Figures 8 and 9).

In P. auriculata the atrial papilla (pa) is much
SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

m bp vs i de ppmavd am pa bd gp ac ode

FIGURE 9.—Polycelis auriculata from Hidaka, Hokkaido, Japan, copulatory apparatus in sagittal

section. [See Figure 2 for abbreviations.]

larger and more pointed than in P. sierrensis. The

copulatory bursa (b) is smaller and forms a pair

of anterolateral extension or horns (see Ijima and

Kaburaki, 1916:168; Kaburaki, 1922:40), while in

P. sierrensis it is a large, lobate sac. Another peculiarity which I noticed in the three specimens of

P. auriculata studied was the formation of an intestinal anastomosis (i) below the copulatory complex, observed also by Okugawa (1938:177), which

was absent in P. sierrensis. This anastomosis or

transversal commissure is lined with the normal

intestinal epithelium and lacks a special muscular

coat such as is seen in a related species from Japan

and Kamchatka, P. schmidti [=Rjabuschinskya

schmidti Zabusov (1916:276); Polycelis ijimai Kaburaki (1922:45)]. This commissure may not be a

specific characteristic of P. auriculata, since anastomoses between the two posterior intestinal rami

are frequently observed in other species as well and

are subject to great individual variation. Kaburaki

(1922:40, fig. 12), in his figure of the digestive system of P. auriculata indicates such an anastomosis

behind the copulatory apparatus. Another species

related to P. sierrensis is P. sabussowi (Seidl) from

Turkestan which has an almost identical structure

of the copulatory organs but lacks the atrial papilla

(see Kenk, 1936).

Polycelis species

Because of the scarcity of sexually mature specimens in the collections of Polycelis and the lack of

external characters which might distinguish the individual taxa, many of the lots taken in the field

could not be identified to species. Unfortunately

this is true for the great majority of the locality

records of the genus in North America. In some

cases the presence of identifiable specimens in the

vicinity of a given locality may give a hint as to

the taxonomic identity of the immature forms but

would not preclude the risk of misidentification. I

am, therefore, listing here all distributional records

known to me which need further study.

ALASKA. (1) to (7) Six streams and one lake on road from

Palmer to Willow (Kenk, 1953:173). (8) to (13) Six streams

on Glen Highway, between Anchorage and Glenallen (Kenk,

1953:173). (14) and (15) Two streams on road from Anchorage to Potter (Kenk, 1953:173) . (16) to (25) Nine Streams

and one lake on Richardson Highway, between Glenallen and

Valdez (Kenk, 1953:173). (26) Stream 9 miles north of Seward

(Holmquist, 1967:463). (27) Near Johnson Pass, 66 miles

from Anchorage (Holmquist, 1967:463).

CALIFORNIA. EL DORADO COUNTY: Tributary of South

Fork of American River, crossing U. S. Highway 50, 5.9 road

miles east of Pacific House; 23 June 1967, water clear,

fast, 10.1 °C, pH 7.3, many specimens under stones.

MARIPOSA COUNTY: (1) Tributary of Yosemite Creek, on

Yosemite Falls Trail, Yosemite National Park; 3 July 1967,

5 specimens. (2) Wildcat Creek, Yosemite National Park,

crossing Big Oak Flat Road, 2.3 miles west of junction with

State Road 140; 3 July 1967, water clear, fast, 14.6°C, pH

7.2, 3 specimens under stones. MONO COUNTY: (1) Convict

Creek in Long Valley, at an altitude of 7200 feet (Kennedy,

1967:8). (2) Stream on Tioga Road (State Road 120) at

timberline near Tioga Pass; 18 October 1970, 7 specimens

collected by Dr. Vida C. Kenk. NEVADA COUNTY: Sagehen

Creek at Sagehen Creek Biological Station, 1.7 road miles west

of State Road 89, north of Truckee; 9 July 1968, water clear,

fast, temperature 18.1 °C, pH over 7.6, oxygen 7 ppm, many

specimens, some with signs of fission; 29 May 1970, 13.0°C,
NUMBER 1S5 13

pH 7.6, many small specimens. SANTA CLARA COUNTY:

Springs of Black Creek, on east slope of Black Mountain,

southwest of Los Gatos; bottom silt with stones; 3 June 1967,

water temperature 11.0° and 11.5°C, pH 6.7, 12 immature

specimens under stones; 25 June 1967, 6 specimens. SANTA

CRUZ COUNTY: (1) Tributary of San Lorenzo River, crossing

State Road 9 at Brookdale; 4 June 1967, water clear, fast,

11.2°C, pH 8.0, one specimen under a stone. (2) Fall Creek,

about i/2 mile west of Felton, San Lorenzo River Valley; 4

June 1967, water clear, fast, 11.6°C, pH 8.3, one specimen

under a stone. (3) Fall Creek, above fork leading to old

mine; 4 July 1968, water clear, fast current, temperature

13.4°C, pH 7.9, 3 worms under stones. (4) Small spring on

right bank of tributary of Fall Creek which leads to old mine;

4 July 1968, water clear, moderate current, temperature

12.3°C, pH 7.4, 2 immature Polycelis under stone and fallen

leaf. (5) Tributary of Fall Creek, at site of old mine; 4 July

1968, water clear, fast, 12.3°C, 3 specimens under stones.

TULARE COUNTY: (1) East Fork of Redwood Creek, in

Sequoia National Forest, crossing State Road 198, 2.2 road

miles east of Bearskin Meadow Road; 27 June 1967, water

clear, fast, 16.1 °C, pH 6.9, 4 immature specimens under

stones. (2) Stream crossing State Road 198, 0.9 mile south

of Camp Kaweah in Sequioa National Park; 28 June 1967,

water clear, fast, 12.2°C, pH 7.2, 4 Polycelis under stones.

(3) Tributary of Kaweah Creek, Sequoia National Park,

crossing State Road 198, 2 miles west of Lodgepole; 28 June

1967, water clear, fast, 9.9°C, pH 6.0, 4 asexual worms under

stones. (4) Tributary of Halstead Creek, crossing State Road

198, 3.7 miles west of Lodgepole, Sequoia National Park; 28

June 1967, water clear, fast, 12.9°C, pH 7.1, one immature

specimen under stone. TUOLUMNE COUNTY: (1) Stream

crossing Tuolumne Grove Road in Yosemite National Park,

2.3 road miles west of junction with Big Oak Flat Road;

3 July 1967, water clear, fast, 11.1 °C, pH 6.2, 4 specimens

on fallen branch. (2) Small seepage spring on right bank of

stream crossing Tioga Road (State Road 120), 5.6 road miles

west of junction with Big Oak Flat Road; 3 July 1967, water

8.4°C, pH 6.0, 2 immature specimens.

COLORADO (see Kenk, 1952:196). BOULDER COUNTY: (1)

to (4) Four streams in the St. Vrain Creek Basin, crossing

State Road 7. GRAND COUNTY: (1) Onahu Creek, crossing

U. S. Highway 34. (2) Tonahutu Creek, above opening into

Grand Lake. LARIMER COUNTY: (1) Thompson River east

of Estes Park. (2) Fall River at Estes Park. (3) Roaring

River (tributary of Fall River).

MONTANA. GALLATIN COUNTY: (1) Small spring on

campus of Montana State University, Bozeman; 1 September

1967, water clear, moderate current, 11.7°C, pH 7.4, many

immature specimens under stones; February and April 1969,

43 specimens collected and sent by Dr. C. J. D. Brown, none

mature. (2) Trout Brook, tributary of East Gallatin River,

north-northwest of Bozeman; 2 September 1967, water clear,

fast current, 9.6°C, pH 7.8, 6 animals under stones. (3)

Spring north of Belgrade, tributary of Thompson Creek,

outlet crossing county road 4.3 miles north of junction of

U. S. Highway 10 and Montana Secondary Road 347; 4

September 1967, 2 immature Polycelis; 4 June 1970, 14.0°C, 3

Polycelis under stones; Dendrocoelopsis vaginata Hyman also

occurs here. LAKE COUNTY: East shore of Flathead Lake,

below mouth of a creek off State Road 35, 12 road miles

north of junction with U. S. Highway 93; 3 September 1967,

one specimen under a stone. MISSOULA COUNTY: Spring and

creek, tributary of Rattlesnake Creek, 1 mile from Clark

Fork River; 21 May 1968, water slightly muddy, 10°C, 4

immature Polycelis collected by F. P. Crowley, together with

Dendrocoelopsis vaginata Hyman. RAVALLI COUNTY: Skalkaho Pass, east of Hamilton, collected by Miss Betty Locker

(see Kenk, 1952:196). YELLOWSTONE NATIONAL PARK (Montana sector): Warm Creek, crossing road from Northeast

Entrance to Tower Falls Junction, 1.2 miles west of entrance

gate; 23 June 1963, water clear, fast, 7.6°C, 4 Polycelis under

stones, some with regenerating tails.

NEW MEXICO. BERNALILLO COUNTY: Stream in Cienega

Canyon, on east slope of Sandia Mountains, in Cibola National Forest; 16 July 1968, water clear, fast, 12.6°C, pH 8.6,

very numerous Polycelis of various sizes, some with indications of preceding fission, none fully mature.

OREGON. CLACKAMAS COUNTY: Spring in Willamette

Park, Willamette (12 miles south of Portland); 12 September

1967, water clear, moderate current, 12.1 °C, pH 6.2, many

specimens, all asexual, some with signs of fission. KLAMATH

COUNTY: (1) Goodbye Creek, Crater Lake National Park,

above bridge which leads from the Park Service headquarters

to State Road 62; 13 September 1967, water clear, fast, 5

immature specimens under stones. (2) Anne Spring, at

south entrance of Crater Lake National Park; 13 September

1967, water clear, 3.1 °C, pH 7.0, 11 specimens under stones,

some with regenerating tail ends. MULTNOMAH COUNTY:

Woodbury Spring, in Crystal Springs area of Eastmoreland

district of Portland; 12 September 1967, water clear, 11.2°C,

pH 6.3, on liver bait many Polycelis, all immature (besides

this species, also Phagocata oregonensis Hyman and Dendrocoelopsis vaginata Hyman). The occurrence of Polycelis in

this area is also mentioned by Hyman (1963:2) and Kenk

(1970:31).

SOUTH DAKOTA. Brook near the State Game Lodge in

the southern part of the Black Hills (Hyman, 1931:124).

UTAH. BEAVER COUNTY: Springs and streams in Puffer

Lake area (Beck, 1954:82). CACHE COUNTY. Rick's Spring in

Logan Canyon, on U.S. Highway 89, 16.6 road miles east of

Utah State University in Logan; 27 September 1967, water

clean, fast, cold, many specimens under stones, some of them

mature but not studied (see also Beck, 1954:82; Braithwaite.

1962:24). Phagocata crenophila Carpenter occurs in the same

locality. Springs and streams in Dagget, Emery, San Juan,

Sanpete, Tooele, Utah, Wasatch, and Wayne counties (Beck,

1954:82; Braithwaite, 1962:24).

WASHINGTON. Streams in Mt. Rainier National Park,

Lewis and Pierce counties (USNM 36070 through 36078).

WISCONSIN. DANE COUNTY: Springs near Lake Mendota

(Muttkowski, 1918:389, as "Polycelis nigra").

WYOMING. TFTON COUNTY: (1) Stream crossing Jackson

Hole highway (U.S. Highway 26), 0.5 mile south of Spread

Creek bridge, Grand Teton National Park; 24 June 1963,

water clear, 11.6°C, Polycelis in fission under stones. (2) Outflow of fish tanks of Jackson National Fish Hatchery, off U.S.

Highway 89, 3i/2 road miles north of Jackson; 29 September

1967, moderate current, water clear, cold, one Polycelis under

a stone. YELLOWSTONE NATIONAL PARK: Twenty-two springs
14 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

and streams in various parts of the Park; 17-25 June 1963, 7-8

September 1967, and 6 June 1970, water temperature 5.4°-

17.3°C, (average 10.3°, 18 measurements), pH 7.7-8.6 (average

8.2, 4 measurements), worms frequently showing signs of

asexual reproduction. Muttkowski (1929:183) reported

"Polycelis nigra" from various streams in the Park. Specimens

from Lava Creek were also collected and sent to me by Jack

L. Dean.

CANADA. ALBERTA: Snaring River, Jasper National

Park (Ball and Fernando, 1968:213).

The American species and subspecies of Polycelis

are probably allopatric in distribution, with some

possible sympatry in marginal areas. If this is the

case, individual unidentified populations may be

assigned, with some confidence, to known forms

occuring in the same geographic area. Thus, all

records from Alaska, northern Wyoming, and Alberta may refer to P. coronata borealis, populations of Montana, New Mexico, and Utah to P.c.

coronata, and those of Colorado and South Dakota

to P.c. brevipenis. It is possible that all Polycelis

from California are P. sierrensis. These questions

will have to be settled by additional collecting,

preferably during the height of the breeding season

(in winter?).

Conclusion

The genus Polycelis is represented in North

America by two species belonging to two subgenera,

P. (Polycelis) coronata (Girard) and P. (Seidlia)

sierrensis, new species, inhabiting the western half

of the continent. P. coronata occurs as three subspecies, P.c. coronata, P.c. borealis, and P.c. brevipenis, differing in the detailed structure of the

copulatory apparatus. The North American forms

cannot be distinguished by external characters

alone, nor can they be identified in immature

stages.

Literature Cited

Ball, I. R., and C. H. Fernando

1968. On the Occurrence of Polycelis (Turbellaria, Tricladida) in Western Canada. Canadian Field-Naturalist, 82:213-216.

Beck, D. E.

1954. Distributional and Natural History Notes on Polycelis coronata (Girard) in Utah. Utah Academy of

Sciences Arts and Letters, Proceedings, 31:79-82.

Benazzi, M.

1963. II Problema Sistematico delle Polycelis del Gruppo

nigra-tenuis alia Luce di Richerche citologiche e

genetiche. Monitore Zoologico Italiano, 70-71:288-

300.

Braithwaite, L. F.

1962. The Taxonomic Problem of Polycelis in the United

States. 32 pages. Unpublished M.S. Thesis, Brigham

Young University.

Carpenter, J. H.

1969. A New Planarian from Utah, Phagocata crenophila

n. sp. (Turbellaria, Tricladida). Transactions of

the American Microscopical Society, 88:274-281.

Diesing, K. M.

1862. Revision der Turbellarien, Abtheilung: Dendrocoelen. Sitzungsberichte der kaiserlichen Akademie

der Wissenschaften, Mathematisch-naturwissenschaftliche Classe, Abtheilung 1, 44:485-578.

Ehrenberg, C. G.

1831. Animalia Evertebrata Exdusis Insectis. In Hemprich

and Ehrenberg, Symbolae Physicae, series 1. Berolini.

Girard, C.

1891. Deux especes nouvelles de Planaires Americaines.

Le Naturaliste (Paris), series 2, 13 (98) :80.

1893. Recherches sur les Planaries et les Nemertiens de

l'Amerique du Nord. Annales des Sciences Naturelles, Zoologie, series 7, 15:145-310, plates 3-6.

Hallez, Paul

1894. Catalogue des Rhabdocoelides, Triclades & Polyclades du Nord de la France. Second edition, 239

pages, 2 plates. Lille.

Holmquist, C.

1967. Dendrocoelopsis piriformis (Turbellaria Tricladida)

and Its Parasites from Northern Alaska. Archiv fur

Hydrobiologie, 62:453-466.

Hyman, L. H.

1931. Studies on the Morphology, Taxonomy, and Distribution of North American Triclad Turbellaria, III:

On Polycelis coronata (Girard). Transactions of the

American Microscopical Society, 50:124-135.

1934. Report on Triclad Turbellaria from Indian Tibet.

Memoirs of the Connecticut Academy of Arts and

Sciences, 10:5-12, plates 1-2.

1951. North American Triclad Turbellaria, XII: Synopsis

of the Known Species of Fresh-Water Planarians

of North America. Transactions of the American

Microscopical Society, 70:154-167.

1953. Turbellaria (Flatworms). In Robert W. Pennak,

Fresh-Water Invertebrates of the United States,

pages 114-141. New York: Ronald Press Company.

1963. North American Triclad Turbellaria, XVI: FreshWater Planarians from the Vicinity of Portland,

Oregon. American Museum Notntates, 2123:1—5.

Ijima, I., and T. Kaburaki

1916. Preliminary Descriptions of Some Japanese Triclads. Annotationes Zoologicae Japonenses, 9:153-

171.
NUMBER 1SS 15

Kaburaki, T.

1922. On Some Japanese Freshwater Triclads; with a

Note on the Parallelism in Their Distribution in

Europe and Japan. Journal of the College of Science, Imperial University of Tokyo, 44 (2): 1-71, 1

plate.

Kenk, R.

1930. Beitrage zum System der Probursalier (Tricladida

Paludicola), III: Versuch einer natiirlichen Gruppierung der Probursalier. Zoologischer Anzeiger,

89:289-302.

1936. Bemerkung zur Trikladenfauna Turkestans. Zoologischer Anzeiger, 115:76-80.

1952. Fresh-Water Triclads (Turbellaria) of the Rocky

Mountain National Park Region, Colorado. Journal

of the Washington Academy of Sciences, 42:193-198.

1953. The Fresh-Water Triclads (Turbellaria) of Alaska.

Proceedings of the United States National Museum, 103:163-186, plates 6-8.

1970. Freshwater Triclads (Turbellaria) of North

America, II: New or Little Known Species of

Phagocata. Proceedings of the Biological Society

of Washington, 83:13-34.

1972. Freshwater Planarians (Turbellaria) of North

America. Biota of Freshwater Ecosystems, Identification Manual, no. 1. (In press.)

Kennedy, H. D.

1967. Seasonal Abundance of Aquatic Invertebrates and

Their Utilization by Hatchery-Reared Rainbow

Trout. Technical Papers of the Bureau of Sport

Fisheries and Wildlife, United States Department

of the Interior, 12:1-41.

Lepori, N. G.

1955. La Differenziazione specifica di Polycelis nigra

Ehrenberg e Polycelis tenuis Iijima (Tricladida,

Paludicola) e la loro Distribuzione geografica in

Europa. Atti delta Societa Toscana di Sdenze

Naturali, series B, 62:50-71.

Miiller, Otho Fridericus

1774. Vermium Terrestrium et FluxAatilium, seu Animalium Infusoriorum, Helminthicorum et Testaceorum, non Marinorum, Succincta Historia.

l(2):-80. Havniae et Lipsiae.

Muth, A.

1912. Beitrage zur Kenntnis der Gattung Sorocelis Grube.

Mitteilungen des Naturwissenschaftlichen Vereines

fur Steiermark, 48:381-410.

Muttkowski, R. A.

1918. The Fauna of Lake Mendota: A Qualitative and

Quantitative Survey with Spedal Reference to the

Insects. Transactions of the Wisconsin Academy

of Sciences Arts and Letters, 19:374-482.

1929. The Ecology of Trout Streams in Yellowstone

National Park. Roosevelt Wild Life Annals, 2:154-

240.

Okugawa, K. I.

1938. [On Sorocelis sapporo and some other Probursalia

(Paludicola)]. Dobutsugaku Zasshi, 50:177.

Seidl, H. H.

1911. Beitrage zur Kenntnis centralasiatischer Tricladen.

Zeitschrift fur wissenschaftliche Zoologie, 98:31-67,

plates 5-7.

Stimpson, W.

1857. Prodromus Descriptionis Animalium Evertebratorum quae in Expeditione ad Oceanum, Pacifkum

Septentrionalem a Republica Federata Missa,

Johanne Rodgers Duce, Observavit et Descripsit, I:

Turbellaria Dendrocoela. Proceedings of the

Academy of Natural Sciences of Philadelphia, 9:19-

31.

Stringer, C. E.

1918. The Free-Living Flatworms (Turbellaria). In

Henry Baldwin Ward and G. C. Whipple, FreshWater Biology, pages 323-364. New York: John

Wiley & Sons.

Zabusov, I. P. [also Sabussow, H., or Zaboussoff, H.]

1911. Izsliedovaniia po Morfologii i Sistematikie Planarii

Ozera Baikala. I. Rod Sorocelis Grube (Untersuchungen fiber die Morphologic und Systematik

der Planarien aus dem Baikalsee. I. Die Gattung

Sorocelis Grube). Trudy Obshchestva Estestvoispytatelei pri Imperatorskom Kazanskom Universitetie,

43 (4): 1-422, 11 plates. Dobavlenie [Appendix], 10

pages.

1916. Rjabuschinskya schmidti n. g. n. sp., novyi vid i

rod Tricladida Paludicola iz Kamchatki (Rjabuschinskya schmidti n. g. n. sp., Espece et Genre nouveau des Tricladida Paludicola du Kamtchatka).

Russkii Zoologicheskii' Zhurnal, 1:273-286.

Addendum

While this paper was in press, an additional record of Polycelis came to the author's attention:

K. Elgmork and O. R. Saether (1970), Distribution of Invertebrates in a High Mountain Brook

in the Colorado Rocky Mountains. University of Colorado Studies, Series in Biology, 31:1-55, 1

folding table. Elgmork and Saether reported Polycelis coronata from North Boulder Creek and

tributary in Boulder County, Colorado (p. 27).

•ft V. S. GOVERNMENT PRINTING OFFICEi 1873—484-322/36

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

IVJ" 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 9b) 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.
K

1

•

"iHr

^ ^MBI