Biostratigraphy of Mississippian 

Lithostrotionoid Corals, 

Lisburne Group, Arctic Alaska

GEOLOGICAL SURVEY PROFESSIONAL PAPER 743-A
BIOSTRATIGRAPHY OF MISSISSIPPIAN

LITHOSTROTIONOID CORALS,

LISBURNE GROUP, ARCTIC ALASKA
a? t - 5 - ^-

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FRONTISPIECE. Panoramic view to the east, south of Cape Lewis, showing the outcrop of the south Cape Lewis section, 68A-9.
Biostratigraphy of Mississippian 

Lithostrotionoid Corals, 

Lisburne Group, Arctic Alaska

By AUGUSTUS K. ARMSTRONG

CONTRIBUTIONS TO PALEONTOLOGY

GEOLOGICAL SURVEY PROFESSIONAL PAPER 743-A

Systematic paleontologic studies of 

five new species of lithostrotionoid 

corals from described sections of 

the Lisburne Group

UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON: 1972
UNITED STATES DEPARTMENT OF THE INTERIOR 

ROGERS G. B. MORTON, Secretary

GEOLOGICAL SURVEY 

V. E. McKelvey, Director

Library of Congress catalog-card No. 77-188160

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

Washington, D.C. 20402 - Price 70 cents (paper cover)

Stock Number 2401-2091
CONTENTS

Abstract _________________________________________

Introduction _____________________________________

Stratigraphic sections _____________________________

North Niak Creek section ______________________

South Niak Creek section ______________________

South Cape Lewis section ______________________

West Sadlerochit Mountains section ____________

Biostratigraphic distribution of Lisburne Group lithostrotionoid corals _______________________________

Systematic paleontology ___________________________

Family Lithostrotionidae d'Orbigny, 1851 ________

Genus Lithostrotion Fleming, 1828 __________

Subgenus Siphonodendron McCoy, 1849 _

Lithostrotion (Siphonodendron) lisburnensis n. sp _________________

Page

Al

1

2

2

2

5

5

6

9

9

9

10

10

Systematic paleontology Continued Pase 

Family Lithostrotionidae d'Orbigny, 1851 Con. 

Genus Lithostrotion Fleming, 1828 Con.

Subgenus Siphonodendron McCoy, 1849 

Continued 

Lithostrotion (Siphonodendron) dutroi n. sp _ _____ _____ A14 

Lithostrotion (Siphonodendron) ignekensis n. sp _____________ 19

Genus Diphyphyllum Lonsdale, 1845 _____ 20

Diphyphyllum nasorakensis n. sp ____ 20

Family Lonsdaleiidae Chapman, 1893 _______ 22

Genus Lithostrotionella Yabe and Hayasaka,

1915 _______________________ 22'

Lithostrotionella niakensis n. sp 23

References cited ________________ _ 25

Index ________________________________ 27

ILLUSTRATIONS

[Plates follow index]

FRONTISPIECE. Panoramic view to the east, south of Cape Lewis, showing the outcrop of the south Cape Lewis section, 68A-9.

PLATE Lithostrotion (Siphonodendron)

Lithostrotion (Siphonodendron)

Lithostrotion (Siphonodendron)

Lithostrotion (Siphonodendron)

Lithostrotion (Siphonodendron)

sp. 

sp.

lisburnensis n.

lisburnensis n.

dutroi n. sp.

dutroi n. sp. and Lithostrotionella niakensis n. sp.

ignekensis n. sp.

Diphyphyllum nasorakensis n. sp. 

Diphyphyllum nasorakensis n. sp. 

Lithostrotionella niakensis n. sp. 

Lithostrotionella niakensis n. sp.

Page

FIGURE 1. Index map of northern Alaska, showing location of coral collections and stratigraphic sections A2

2. Chart showing stratigraphic distribution of colonial rugose corals __________ 3

3. Diagram showing stratigraphy and coral distribution in the north Niak Creek section, 68A-12, and the

south Niak Creek section, 68A-13 _________________________________________ 4

4. Photograph of lithostrotionoid coral colonies at the base of section 68A-12 ___________ 5

5. Photograph of the base of section 68A-13 _____________________________ - 6

6. Photograph of lithostrotionoid biostrome in section 68A-13 _______________________ 7

7. Diagram showing stratigraphy and coral distribution in the south Cape Lewis section, 68A-9 8

8. Index map of section 68A-9 and location of type specimen of Diphyphyllum nasorakensis and paratypes of

Lithostrotion (Siphonodendron) lisburnensis _______________________________________ 9

9-12. Photographs of 

9. Section 68A-9, showing stratigraphic footage along line of traverse _____ 10

10. A persistent Lithostrotion (Siphonodendron) sinuosum bed in section 68A-9 11

11. Cape Lewis and upper part of section 68A-9, showing Lithostrotionella biostrome at 880- to 900- 

foot level ______________________________________________ 12

12. Large Thysanophyllum sp. corallum in biostromal beds 895 feet above the base of section 68A-9 _ 13

13. Diagram showing stratigraphy and coral distribution in the west Sadlerochit Mountains section, 69A-1 13

14. Index map of section 69A-1 and location of type specimens of Lithostrotion (Siphonodendron) ignekensis _ 14

15. Photograph of upper part of section 69A-1, showing stratigraphic footage along line of traverse 15

16. Diagrams showing corallite diameter and number of major septa in Lithostrotion (Siphonodendron) lisburnensis n. sp ___________________________________ _ 17
VI CONTENTS

Page

FIGURE 17. Sections of Lithostrotion (Siphonodendron) lisburnensis n. sp _________ _ A17

18. Diagrams showing corallite diameter and number of major septa in Lithostrotion (Siphonodendron) dutroi

n. sp _______________________________________________ _ 17

19. Sections of Lithostrotion (Siphonodendron) dutroi n. sp _________________ 18

20. Diagram showing corallite diameter and number of major septa in Lithostrotion (Siphonodendron) ignekensis n. sp __________________________________________ __ - 18

21. Sections of Lithostrotion (Siphonodendron) ignekensis n. sp ____________________ __ ___ 18

22. Diagram showing corallite diameter and number of major septa in Diphyphyllum nasorakensis n. sp _ 21

23. Sections of Diphyphyllum nasorakensis n. sp ___________________________-_ ____ 21

24. Diagrams showing corallite diameter and number of major septa in Lithostrotionella niakensis n. sp __ 23

25. Sections of Lithostrotionella niakensis n. sp ____________________ _ _ _ 24
CONTRIBUTIONS TO PALEONTOLOGY

BIOSTRATIGRAPHY OF MISSISSIPPIAN LITHOSTROTIONOID 

CORALS, LISBURNE GROUP, ARCTIC ALASKA

By AUGUSTUS K. ARMSTRONG

ABSTRACT

The biostratigraphy of four measured sections of the Lisburne Group is described: South Cape Lewis section, north 

Niak Creek section, and south Niak Creek section, all in 

northwestern Alaska; and the west Sadlerochit Mountains 

section, in northeastern Alaska. In addition, one new species 

of coral is described from the well-documented Shainin Lake 

section, in north-central Alaska.

Within the Lisburne Group carbonate rocks, lithostrotionoid 

corals are known only in Meramec age or younger beds. They 

are represented by 16 taxa and abundant individuals in 

strata of Meramec and very earliest Chester age, but they are 

rare in beds younger than earliest Chester. Middle and late 

Chester age beds contain only three taxa of lithostrotionoid 

corals.

Five new species of lithostrotionoid corals are described 

from the Mississippian part of the Lisburne Group: Lithostrotionella niakensis n. sp. and Lithostrotion (Siphonodendron) dutroi n. sp. from middle Meramec age beds, Lithostrotion (Siphonodendron) lisburnensis n. sp. and Diphyphyllum 

nasorakensis n. sp. from late Meramec and earliest Chester 

age beds, and Lithostrotion (Siphonodendron) ignekensis n. 

sp. from middle and late Chester age beds.

INTRODUCTION

The most conspicuous macrofaunal elements in 

much of the Lisburne Group carbonate rocks are 

the large colonial corals. The primary objective of 

this study is to describe five new species of lithostrotionoid corals and their stratigraphic ranges.

The system of microf ossil assemblage zones developed by Bernard L. Mamet has been applied to the 

Lisburne Group of arctic Alaska in a series of papers (Armstrong and others, 1970, 1971; Armstrong and Mamet, 1970). The use of these zones 

has permitted detailed correlation among the surface sections of the Lisburne Group shown in figure 

1 and between the Carboniferous type sections of 

Eurasia and North America (fig. 2).

Most of the corals appear to have stratigraphic 

ranges that extend through two or more microfossil 

zones. Plotting the stratigraphic distribution of the

lithostrotionoid corals on the microfossil zones chart 

shows the vertical distribution of the lithostrotionoid corals within the Lisburne Group.

Armstrong's (1970b) study described the .biostratigraphy and the lithostrotionoid corals from the 

Meramec age parts (zones 13-15) of Sable and Dutro's (1961) Kogruk Formation of the DeLong 

Mountains and Campbell's (1967) Nasorak Formation of the Cape Thompson area. The following taxa 

were reported: Lithostrotion (Siphonodendron) sinuosum (Kelly), L. (S.) warreni Nelson, Lithostrotion (Siphonodendron) sp. A, Lithostrotionella 

banffensis (Warren), L. aff. L. banffensis (Warren), L. birdi Armstrong, L. mclareni (Sutherland), 

Lithostrotionella sp. A, Lithostrotionella sp. B, Thysanophyllum orientale Thomson, T. astraeiforme 

(Warren), Thysanophyllum sp. A, Sdophyllum lambarti Harker and McLaren, S. alaskaensis Armstrong, and Sciophyllum sp. A.

The corals from the Lisburne Hills seacliffs were 

collected by J. Thomas Dutro, Jr., and myself in 

July and August 1968. I thank Irvin L. Tailleur, the

1968 field party chief, and Hillard N. Reiser, the

1969 field party chief, for their support of paleontologic and stratigraphic field studies and their stimulating discussions of regional geology and structural 

and stratigraphic problems.

I also thank the Naval Arctic Research Laboratory (Barrow), Office of Naval Research, for their 

support of my field activities.

I am most grateful to Dr. Bernard L. Mamet, 

University of Montreal, for his studies of the microfossils in the carbonate rock thin sections and 

for his age determinations of the stratigraphic sections.

The coral thin sections were cut by Robert Shely, 

and the photographs were made by Kenji Sakamoto, 

both of the U.S. Geological Survey.

Al
A2 CONTRIBUTIONS TO PALEONTOLOGY

168 C 164' 160' 156 152' 148' 144' 140°

68

FIGURE 1. Index map of northern Alaska, showing location of coral collections and stratigraphic sections described and illustrated in this report.

Special thanks are given J. Thomas Dutro, Jr., 

W. A. Oliver, Jr., and W. J. Sando for their help 

during preparation of the manuscript and their 

critical review of the manuscript.

STRATIGRAPHIC SECTIONS

The five new species of lithostrotionoid corals described in this report are from five measured sections of the Lisburne Group (fig. 1). Three sections 

are in northwestern Alaska: south Cape Lewis, 

68A-9; south Niak Creek, 68A-13; and north Niak 

Creek, 68A-12. The west Sadlerochit Mountains 

section, 69A-1, is in the Sadlerochit Mountains, 

northeastern Brooks Range, northeastern Alaska. 

Bowsher and Dutro's (1957) well-documented 

Shainin Lake section, central Brooks Range, which 

yields Lithostrotion (Siphonodendron) dutroi n. sp., 

is not illustrated in this report. All these sections 

have been carefully sampled for microfossils. The 

stratigraphic ranges of the new species of corals 

are plotted with respect to the microfossil assemblage zones in figure 2. The microfaunal assemblage 

zones are also shown on the illustrations of the 

stratigraphic sections.

NORTH NIAK CREEK SECTION

The extensively dolomitized carbonate rocks of 

the Kogruk Formation, of Meramec age, were studied in the seacliff exposures at the north Niak Creek

section, 68A-12 (fig. 3). This section, north of Niak 

Creek, appears to be an allochthonous, rootless 

thrust sheet and is an incomplete exposure of the 

Kogruk Formation. The base and top of the section 

are delineated by fault zones. The lower 25 feet of 

the section is characterized by an argillaceous 

dark-gray limestone which contains abundant Foraminifera and lithostrotionoid corals (fig. 4). Corals 

are present sporadically between 480 and 625 feet 

from the top of the section, but specific identification is impossible owing to the poor preservation resulting from the extensive dolomitization and from 

the silicification of the coralla and their internal 

structures.

SOUTH NIAK CREEK SECTION

The south Niak Creek section 68A-13 (fig. 3), 

appears to be in an allochthonous thrust sheet overriding the allochthonous carbonate rocks of section 

68A-12 (Armstrong and others, 1971, fig. 9). This 

section, south of Niak Creek, is incomplete because 

of faulting. It is 215 feet thick and is a partial representation of the lower part of the Nasorak Formation. The rocks are dark-gray shale and argillaceous limestone that contain an abundant 

lithostrotionoid coral fauna (figs. 5, 6). The microfossils (Armstrong and others, 1971) indicate that 

the rocks are at the top of zone 15, very near the 

Meramec-Chester boundary.
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A4 CONTRIBUTIONS TO PALEONTOLOGY

INDEX MAP TO SECTIONS 68A-12 AND 68A-13

FIGURE 3. Stratigraphy and coral distribution in the north Niak Creek section, 68A-12, and the south Niak Creek 

section, 68A-13. Note that section 68A-12 was measured down from the top; 68A-13, up from the bottom.
MISSISSIPPIAN LITHOSTROTIONOID CORALS, LISBURNE GROUP, ALASKA A5

FIGURE 4. Lithostrotionoid coral colonies (shown by arrows) at the base of section 68A-12, north of Niak Creek. The bedding surface and the sides of the bed contain numerous coralla. Although coralla are very abundant, only three species of 

colonial rugose corals are present. (See fig. 3.) Below the 715-foot level is a thick zone of tectonic breccia.

SOUTH CAPE LEWIS SECTION

The south Cape Lewis section, 68A-9 (figs. 7, 8), 

is also in an allochthonous thrust sheet. The section 

is magnificently exposed south of Cape Lewis in a 

series of seacliffs (frontispiece; fig. 9). The lower 

1,280 feet of the section is the Nasorak Formation 

(Chester, zone 16i age) and is composed of darkgray shale, argillaceous limestone, and cherty limestone. In figures 7 and 9 the dark-gray shale is evident from 0 to 230 feet and from 350 to 650 feet 

above the base. Corals are abundant from 50 to 325 

feet above the base. The fasciculate corals Lithostrotion (Siphonodendron) spp. and Syringopora

spp. are particularly abundant and are the major 

constituent of many horizons (fig. 10). Fasciculate 

and cerioid corals form a biostromal bed and possibly also a patch reef that is well exposed at 

880-900 feet above the base (fig. 11). Large cerioid 

coralla which average 1.5-3 feet in diameter are 

abundant (fig. 12). The location of the biostromal 

bed and the stratigraphic footage from 900 to 1,500 

feet are shown in figure 11.

WEST SADLEROCHIT MOUNTAINS SECTION

The west Sadlerochit Mountains section, 69A-1 

(figs. 13, 14), on the west end of the Sadlerochit 

Mountains in northeastern Alaska, was measured in
A6 CONTRIBUTIONS TO PALEONTOLOGY

FIGURE 5. Base of section 68A-13; numbers refer to stratigraphic thickness. Beds between 5 and 65 feet contain 

abundant large coralla. In the foreground is Niak Creek 

crossing the beach gravel; view is to the south.

beds that are autochthonous. The section comprises 

the Alapah Limestone, of Late Mississippian age, 

and the Wahoo Limestone, of Pennsylvanian age in 

this area (fig. 15). The carbonate rocks range in 

composition from oolitic limestone and lime mudstone to dolomite and range in age from Chester 

(zone 16i) to Atoka (zone 21). In general, corals 

are rare in these carbonates; within Chester age 

sediments, colonial rugose corals are found only at 

1,110-1,120 feet above the base (fig. 15).

BIOSTRATIGRAPHIC DISTRIBUTION OF 

LISBURNE GROUP LITHOSTROTIONOID CORALS

The stratigraphic distribution of the lithostrotionoid corals from the Lisburne Group (fig. 2) is 

based on material collected from 27 measured sections (fig. 1). The sections were measured with a 

Jacob staff, and lithologic samples were collected 

every 5 to 10 feet for petrographic and foraminiferal studies (Armstrong and others, 1970, 1971; 

Armstrong and Mamet, 1970). Bernard L. Mamet 

has established microfossil zones for each of these 

stratigraphic sections.

The known vertical stratigraphic distribution of 

the lithostrotionoid corals is shown in figure 2 on a

geologic time scale based on Mamet's microfossil assemblage zones. Lithostrotionoid corals are not 

known in pre-Meramec age rocks of the Lisburne 

Group. On the basis of microfossils, Armstrong, 

Mamet, and Dutro (1970) reported that the oldest 

known carbonates in the central and eastern Brooks 

Range are early Keokuk, Osage age (zone 8), and 

Mamet (oral commun., 1970) reported that the oldest known carbonates in the Kogruk Formation of 

the DeLong Mountains are also Osage (zone 8). 

Present knowledge indicates that carbonate deposition in the Lisburne Group began after the decline 

and extinction of the widespread Cordilleran lithostrotionoid coral fauna of late Kinderhook and earliest Osage age (zone 7) consisting of Lithostrotionella microstylum (White), L. micro, Kelly, and L. 

lochmanae Armstrong. An abundant and widespread coral assemblage developed in the Lisburne 

carbonate facies during latest early, middle, and 

late Meramec time and very earliest Chester time 

(top of zone 12 through lower part of zone 16i). 

The lithostrotionoids then declined markedly in 

earliest Chester time (zone 16i).

Stratigraphic and taxonomic studies of the lithostrotionoid corals from the Lisburne Group indicate 

that none of the species of the 12 taxa shown in 

figure 2, which are characteristic of the late Meramec age carbonates, persist very far stratigraphically into zone 16i of early Chester. Furthermore, in 

the Chester no great number of new species or 

numbers of individuals replace the Meramec corals. 

The thick sequence of Chester age carbonates in the 

region from Itkillik River east to the Sadlerochit 

Mountains (Armstrong and others, 1970) contains 

very few colonial rugose corals. A relatively rare 

coral species in these Chester age beds is Lithostrotion (Siphonodendron) ignekensis n. sp., from zones 

17 and 18 of the Alapah Limestone in the Sadlerochit Mountains. At Cape Lewis, the very poorly preserved colonial rugose corals found in zones 16s and 

17, in the Chester age beds, appear to be two new 

rather rare species of Lithostrotionella (Armstrong 

and others, 1971).

The abrupt and spectacular decline (fig. 2) of the 

Lisburne Group lithostrotionoid corals in the upper 

part of zone 15 and the lowest part of zone 16i 

probably represents a shift in ecological conditions 

in latest Meramec time over a large part of arctic 

Alaska. The open-marine carbonate facies of zones 

14 and 15 of the Kogruk Limestone in the western 

Brooks Range and of the Alapah Limestone in the
MISSISSIPPIAN LITHOSTROTIONOID CORALS, LISBURNE GROUP, ALASKA A7

TIGURE 6. Lithostrotionoid biostrome in section 68A-13. Letters a and g are colonies of Lithostrotionella; 6 is a biostromal 

zone, 6 inches to 2 feet thick, of Lithostrotion (Siphonodendron) sinuosum and L. (S.) warreni; c, d, e, and / are colonies 

of L. (S.) Hsburnensis. The biostrome is approximately 140-146 feet above the base of the section.
A8 CONTRIBUTIONS TO PALEONTOLOGY

FIGURE 7. Stratigraphy and coral distribution in the south Cape Lewis section, 68A-9.
MISSISSIPPIAN LITHOSTROTIONOID CORALS, LISBURNE GROUP, ALASKA A9

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FIGURE 8. Index map of section 68A-9 and location of type 

specimen of Diphyphyllum nasorakensis and paratypes of 

Lithostrotion (Siphonodendron) lisburnensis. See figures 9 

and 11 for photographs of the outcrops and for locations of 

the fossils.

central eastern Brooks Range contains abundant 

lithostrotionoid corals, but corals are rare in essentially similar carbonate facies of the upper part of 

zone 16i and above.

The factors which caused the decline of the lithostrotionoid corals at or slightly above the Meramec-Chester boundary are not known. No sudden 

change in environment of deposition is portrayed in 

the carbonate rock types across this boundary. The 

Chester age Lisburne carbonate beds are primarily 

crinoid-bryozoan packstones and wackestones and 

lime mudstones and are lithologically similar to the 

underlying coral-rich Meramec age beds. These 

Meramec and Chester age beds are supposedly facies equivalents and represent similar environments. 

I provisionally suggest that subtle changes in the 

regional temperature and (or) salinity of the water 

altered conditions for lithostrotionoid coral growth 

and development but did not markedly change the 

living conditions required for prolific echinoderm 

and bryozoan life.

The Meramec age (zones 13-15) Lisburne Group 

coral fauna contains the following species in common with the Peratrovich Formation on Prince of 

Wales Island, southeastern Alaska (Armstrong,

1970a): Lithostrotion (Siphonodendron) warreni 

Nelson, Lithostrotionella birdi Armstrong, L. banffensis (Warren), Thysanophyllum astraeiforme 

(Warren), Sciophyllum alaskaensis Armstrong, and 

Diphyphyllum klawockensis Armstrong.

The Lisburne Group corals which occur in microfaunal assemblage zone 14 correspond approximately to Macqueen and Bamber's (1968) faunal 

zone 3 for the Mississippian rocks of Alberta, Canada. The corals which are found in microfaunal 

zone 15 in the Lisburne Group correspond approximately to Macqueen and Bamber's faunal assemblage zone 4 for Alberta.

Macqueen and Bamber's (1968) faunal list for 

the Mount Head Formation, southwestern Alberta, 

shows only three species that are conspecific with 

the Lisburne Group lithostrotionoids. They are 

Lithostrotion (Siphonodendron) warreni Nelson, 

Lithostrotionella mclareni (Sutherland), and Thysanophyllum astraeiforme (Warren).

Sando, Mamet, and Dutro's (1969, p. E7) list of 

lithostrotionoids from the Mississippian of the 

northern Cordilleran of the United States shows no 

species in common with those from the Lisburne 

Group.

SYSTEMATIC PALEONTOLOGY

Oliver (1968, p. 27) considered that, for Paleozoic 

corals, a sample of 20 corallites adequately characterizes a corallum and that a sample of 20 coralla 

can be considered representative of a local population from one environment over a limited area. Although the criterion for numbers of coralla was not 

met in describing the new species, fairly large numbers of coralla were available for study. 

Morphological terminology follows that of Hill 

(1956, p. F234-F251).

Conventional treatment has been followed in the 

taxonomic hierarchy above the species level. The 

classification is generally that of Hill (1956), but 

some minor changes have been made. The terminology of the microstructure is that of Kato (1963).

Phylum COELENTERATA

Class ANTHOZOA

Order RUGOSA Milne-Edwards and Haime, 1850 

Family LITHOSTROTIONIDAE d'Orbigny, 1851

Genus LITHOSTROTION Fleming, 1828

Lithostrotion Fleming, 1828, A history of British animals,

Edinburgh, p. 508. 

Lithostrotion Fleming. Hill, 1956, in Moore, ed., Treatise on

invertebrate paleontology, Part F, Geol. Soc. America,

p. F282.

Type species. (Opinion 117, International Commission of Zoological Nomenclature) Lithostrotion
A10 CONTRIBUTIONS TO PALEONTOLOGY

FIGURE 9. Section 68A-9, showing stratigraphic footage along line of transverse. Between 230 and 320 feet, fasciculate

colonial corals are very abundant. View is to the east.

striatum Fleming, Lower Carboniferous, British 

Isles.

For a detailed synonymy of the genus see Hill 

(1940, p. 165,166; 1956, p. F282).

Diagnosis. Phaceloid or cerioid corallum; typically with columella, long major septa, and large 

conical tabulae that are generally supplemented by 

outer, smaller, nearly horizontal tabulae; dissepiments absent in very small forms, normal and well 

developed in large forms; increase nonparricidal; 

diphymorphs common (Hill, 1956, p. F282).

Subgenus SIPHONODENDRON McCoy, 1849

Siphonodendron McCoy, 1849, Annals and Mag. Nat. History,

p. 127. 

Siphonodendron McCoy. Sando, 1963, Jour. Paleontology, v.

37, no. 5, p. 1075.

Type species. Lithostrotion pauciradicdis (McCoy), Carboniferous, Ireland.

Diagnosis. Same internal features as Lithostrotion except the corallum is fasciculate.

Lithostrotion (Siphonodendron) lisburnensis n. sp.

Plate 1, figures 1-5; plate 2, figures 1-7

Material. Fragments, each approximately 

10X10X10 cm (centimeters), of 17 coralla were collected by J. T. Dutro, Jr., and myself within carefully measured and sampled stratigraphic sections. 

A minimum of one transverse and one longitudinal 

2- by 3-inch thin section was cut of each corallum. 

The 17 coralla are well preserved and are type material. Approximately 30 corallites were studied and 

measured in each corallum. Most coralla are preserved by calcite, with only minor amounts of silica, 

and in general the preservation of microstructure is 

good to excellent.
MISSISSIPPIAN LITHOSTROTIONOID CORALS, LISBURNE GROUP, ALASKA All

Description. The holotype, USNM 161064 (pi. 1, 

figs. 1-4), is a dendroid corallum with offsets that 

arise by lateral increase. In transverse thin section, 

corallites are 0.5-4 mm (millimeters) apart. Corallites are 2.3-2.8 mm in diameter and have 14-16 

long major septa (figs. 16, 17). The major septa are 

0.7-1.0 mm long and commonly reach the columella. 

Minor septa are well developed and are 0.2-0.4 mm 

long. The corallite wall is 40-60 microns thick, and 

the major septa are 50-60 microns thick at the periphery of the corallum and taper axially. The microstructure of the septa, walls, and dissepiments 

appears to be formed of fibrous calcite and is similar to Kato's (1963, fig. 17c) fibrous structure. The 

septa in the tabularium are commonly recrystallized 

into a mosaic of 5- to 10-micron calcite crystals and 

are not uncommonly silicified. Well-preserved specimens indicate that the microstructures of the corallite wall and septa are very similar (pi. 1, figs. 2, 

3). The columella is lens shaped in cross section, 0.5 

mm long and 0.25 mm wide, and is commonly continuous with the counter septa. Some diphymorphic 

corallites are present.

In longitudinal section the tabulae are generally 

complete and slope away from the columella for a 

distance of approximately 0.8 mm at an angle of 

about 45° from the horizontal before bending downward to an angle of about 80° adjacent to the dissepiments. Ten to twelve tabulae occur in a vertical 

distance of 5 mm. A dissepimentarium is generally 

present and consists of slightly globose, elongated 

dissepiments (fig. 17). Microscopic examination of 

the junction of the tabulae and the columella clearly 

indicates that the tabulae do not contribute to the 

structure of the columella (pi. 1, fig. 3).

Paratype USNM 161056 (pi. 2, fig. 5) is similar 

to the holotype in most morphological features, but 

it differs in having slightly smaller corallites with a 

diameter of 1.5-2.4 mm, 11-13 major septa (fig. 

16), and dissepiments which are somewhat more 

globose.

Paratypes USNM 161060 (not figured) and 

161061 (pi. 2, figs. 2, 3) are similar to the holotype 

except that the dissepimentarium is less well developed and occasionally absent, as shown by longitudinal sections of the corallites.

The remaining paratypes do not differ from the 

above material in any significant morphological features.

FIGURE 10. A persistent Lithostrotion (Siphonodendron) 

sinuosum bed in section 68A-9. The bed is 6-10 inches thick 

and is approximately 235 feet above the base of the section. 

Between 230 and 265 feet this species, L. (S.) warreni, and 

Diphyphyllum nasorakensis are very common. Cerioid 

colonial corals are rare.

Occurrence. The holotype, USNM 161064, was 

collected south of Niak Creek approximately 13 feet 

above the base of measured section 68A-13 (figs. 3, 

5). Three paratypes were also collected from this 

section: USNM 161065, at 15 feet above the base; 

USNM 161066, at 21 feet; and USNM 161067, at 

180 feet. The corals are associated with a microfauna (Armstrong and others, 1971) of latest Meramec age (upper part of zone 15) and earliest Chester age (zone 16i). Other colonial corals found in 

association are Lithostrotion (Siphonodendron) sinuosum (Kelly), L. (S.) warreni Nelson, Diphyphyllum nasorakensis n. sp., Lithostrotionella banffensis 

(Warren), Sciophyllum lambarti Harker and McLaren, and S. alaskaensis Armstrong.

456-832 0-72-3
A12 CONTRIBUTIONS TO PALEONTOLOGY

FIGURE 11. Cape Lewis and upper part of section 68A-9, showing biostromal bed (arrow) at 880- to 900-foot level. Line of

traverse and stratigraphic footage are also shown. View is to the north.

Section 68A-9, south of Cape Lewis (figs. 7, 11), 

has yielded 13 paratypes of L. (S.) lisburnensis. 

These occur in beds of earliest Chester age (zone 

16i) and are found associated with the above coral 

fauna (fig. 9). These paratypes are:

Feet above 

base of 

section 

USNM No. 68A-9

161063 ___________________________ 899 

161062 ___________________________ 899 

161061 ___________________________ 895 

161060 ___________________________ 890 

161059 ___________________________ 885 

161058 ___________________________ 878 

161057 ___________________________ 878 

161056 ___________________________ 855 

161055 .___________________________ 303 

161054 ___________________________ 257 

161053 ___________________________ 263 

161052 ___________________________ 241 

161051 ___________________________ 147

L. (S.) lisburnensis n. sp. is known only from 

sections 68A-9 and 68A-13 in the Lisburne Peninsula region of arctic Alaska. No corals similar to 

this species are reported from the Meramec age carbonates of the Kogruk Formation, DeLong Mountains (Armstrong, 1970b), and L. (S.) lisburnensis 

has not been found in the coral collections made from 

the Lisburne Group of the central and northeastern 

Brooks Range.

Remarks. Lithostrotion (Siphonodendron) lisburnensis n. sp. is very similar morphologically to 

the European Visean species Lithostrotion junceum 

(Fleming) as redescribed by Hill (1940, p. 

171-173), except that in the Visean species "dissepiments are never developed" (p. 172), and diphymorphic corallites may occur. L. (S.) lisburnensis 

always has a single row of dissepiments, and the 

major and minor septa are generally longer than in 

L. junceum (Fleming).
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A14 CONTRIBUTIONS TO PALEONTOLOGY

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FIGURE 14. Index map of section 69A-1 and location of type 

specimens of Lithostrotion (Siphonodendron) ignekensis.

except that L. (S.) genevievensis has a slightly 

larger corallite diameter (4.5 mm) and no minor 

septa.

Lithostrotion (Siphonodendron) dutroi n. sp. (pi. 

3, figs. 1-7) from the lower part of the Alapah 

Limestone, Lisburne Group, Shainin Lake, and the 

lower part of the Lisburne Group, Hulahula River, 

Romanzof Mountains, is easily distinguished from 

L. (S.) lisburnensis by corallites that are 1.0-2.1 

mm in diameter and that have 9-13 long major 

septa, all of which reach the columella, and a corallite spacing of 0.2-0.5 mm.

The Lisburne Group Lithostrotion (Siphonodendron) ignekensis n. sp. (pi. 5, figs. 1-5) of middle 

and late Chester age from the Sadlerochit Mountains is distinguished from L. (S.) lisburnensis n. 

sp. by its larger corallite diameter (3-5 mm), 

higher septal count (14-18), long sinuous counter 

septa, and thin columella.

Lithostrotion (Siphonodendron) sinuosum (Kelly, 

1942) is readily distinguished from L. (S.) lisburnensis n. sp., which occurs abundantly in the same 

beds, by its larger corallite diameter of 3-4.5 mm, 

its 16-19 major septa, and its tendency to have amplexoid major septa in some corallites. Coralla 

which are morphologically transitional between L. 

(S.) lisburnensis n. sp. and L. (S.) sinuosum have 

not been found in the large collections made at the 

south Niak Creek section (68A-13) or at the south 

Cape Lewis section (68A-9).

Name. L. (S.) lisburnensis is derived from the 

Lisburne Hills, which form the seacliffs of northwestern Alaska.

Lithostrotion (Siphonodendron) dutroi n. sp.

Plate 3, figures 1-7; plate 4, figures 1, 3-5

Material. Fragments, each approximately 

10 X10 X15 cm, of six coralla were available for study. 

Two transverse and two longitudinal thin sections 

were cut from the holotype, and one transverse and 

one longitudinal thin section were cut from each of 

the five paratypes. Approximately 200-400 corallites from each colony were studied in thin section. 

The coralla are preserved by calcite, and preservation of the microstructure is good.

Description. The holotype, USNM 161085 (pi. 3, 

figs. 1-7), is a dendroid corallum, but commonly 

two or more corallites may be in contact for some 

distance. When two or more corallites are in contact, the corallite walls have three to six straight to 

slightly curved sides. Typically the corallites are cylindrical and are commonly in contact, but they may 

be separated from each other by a distance of 

200-500 microns.

In transverse section the corallites of the holotype 

are 1-1.7 mm in diameter and have nine to 12 long 

major septa (figs. 18, 19). The corallite walls are 

60-100 microns thick. The major septa are 50-60 

microns thick at the periphery of the corallite, 

taper toward the axis, and are generally fused with 

the columella. The lens-shaped columella is formed 

by the axial ends of the cardinal and counter septa. 

The minor septa are 200-300 microns long and extend into the tabularium. Both classes of septa are 

continuous through the narrow (100-250 microns 

wide), discontinuous dissepimentarium.

No diphymorphic corallites were seen in the holotype.

In transverse section the walls and septa are composed of fibrous calcite similar to the fibrous calcite 

of Kato's (1963, fig. 17c) wall structure (pi. 3, figs.
MISSISSIPPIAN LITHOSTROTIONOID CORALS, LISBURNE GROUP, ALASKA A15

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FIGURE 15. Upper part of section 69A-1, showing stratigraphic footage along line of traverse. Arrow a points to locality of 

the holotype of Lithostrotion (Siphonodendron) ignekensis n. sp. Arrow 6 shows locality in upper beds of Wahoo Limestone where Atoka age Lithostrotionella sp. was collected. View is to the south.

1, 2, 5, 6). The corallite wall in many well-preserved 

specimens shows an outer, dark layer 20-30 microns thick and an inner, lighter fibrous layer 

30-40 microns thick.

In longitudinal section the tabulae are generally 

complete and slope away from the columella at angles of 40°-50° from the horizontal. Approximately 

10-12 tabulae occur in a vertical distance of 5 mm. 

The discontinuous dissepimentarium is composed of 

a single row of globose dissepiments. There are 

16-20 dissepiments in a distance of 5 mm. The columella is slightly sinuous, is thick, and is formed by 

the axial ends of the major septa. The tabulae and 

dissepiments are 10-20 microns thick and are 

formed by crystals of fibrous calcite less than 5 microns in size.

The five paratypes, USNM 161086-161090, are 

nearly identical morphologically with the holotype 

(pi. 4, figs. 1, 3-5). No diphymorphic corallites 

were found in the paratypes.

Occurrence. The holotype, USNM 161085, was 

collected by the writer in 1964 from Bowsher and
A16 CONTRIBUTIONS TO PALEONTOLOGY

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EXPLANATION

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68A-13+ 14C; USNM 161064; holotype

68A-9 + 890B; USNM 161060

+

68A-9 + 895K; USNM 161062

-

D

68A-9 + 899S; USNM 161063

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EXPLANATION

_

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68A-9 + 263B; USNM 161053 68A-9 + 895; USNM 161061

o 

68A-9+ 147; USNM 161051 68A-9 + 885X; USNM 161059

-

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12 13 14 15

NUMBER OF MAJOR SEPTA

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Dutro's (1957) type section of the Alapah Limestone at Shainin Lake. A detailed description and illustrations of this section can be found in their report. The corallum was collected from a bed 185 

feet above the base of the Alapah Limestone and 

was found in association with Lithostrotion (Siphonodendron) warreni Nelson, Lithostrotionella 

banffensis (Warren), Lithostrotionella mclareni 

(Sutherland), Thysanophyllum astraeiforme (Warren), and Sciophyllum sp. The microfauna associated with the holotype is of middle Meramec age 

(zone 13) (Armstrong1 and others, 1970).

EXPLANATION

o 

68A-9 + 303: USNM 161055

68A-9 + 241E; USNM 161052

EXPLANATION

-68A-13+180B: USNM 161067 68A-13 + 21C; USNM 161066

o 

68A-13+15;USNM 161065 68A-13 + 21C; USNM 161066

11 12 13 14 15

NUMBER OF MAJOR SEPTA

16 17

The five paratypes, USNM 161086-161090, were 

collected in 1969 by J. Thomas Dutro, Jr., and myself from outcrops of the Alapah Limestone, Lisburne Group, on the west bank of the west fork of 

the Hulahula River in sec. 2, T. 5 S., R. 31 E., arctic Alaska. The paratypes were found associated 

with a coral and foraminiferal fauna of Meramec 

age.

Field studies in 1970 revealed L. (S.) dutroi to be 

a common coral in the Meramec age beds of the Lisburne Group in the Franklin and Romanzof Mountains, Brooks Range, northeastern Alaska.
MISSISSIPPIAN LITHOSTROTIONOID CORALS, LISBURNE GROUP, ALASKA A17

= 3

EXPLANATION

o 

68A-9 + 257; USNM 161054

68A-9 + 878E; USNM 161058 

_68A-9 + 850-855A; USNM 161056

68A-9 + 878D; /o ' 

USNM 161057 ...-'

11 12 13 14 15 16

NUMBER OF MAJOR SEPTA

17 18

FIGURE 16. Corallite diameter and number of major septa in 

Lithostrotion (Siphonodendron) lisburnensis n. sp. Each 

unnumbered symbol represents a single corallite; if more 

than one corallite shows the same diameter and number of 

septa, the number of similar corallites is shown.

10 mm

FIGURE 17. Sections of Lithostrotion (Siphonodendron) lisburnensis n. sp. (USNM 161064).

This species was not reported from the Kogruk 

Formation of the DeLong Mountains (Armstrong, 

1970b), and it is not known from the Lisburne 

Group exposures in the Lisburne Hills, which form 

the seacliffs of northwestern Alaska.

Remarks. Lithostrotion (Siphonodendron) dutroi n. sp. is sharply delineated from all other species of Lithostrotion (Siphonodendron) found in the 

Lisburne Group of arctic Alaska by its small corallite diameter of 1.0-2.1 mm, nine to 13 long major 

septa, and well-developed minor septa and columella. In hand specimen the corallum is distinctive

W103A;USNM 161085; 

holotype

69R-3; USNM 161088; paratype

 

69R-3; USNM 16109; paratype

_J_______1_______I_____

EXPLANATION

A

69R-3; USNM 161086; paratype

o 

69R-3; USNM 161087; paratype

 

69R-3; USNM 161089; paratype

i_______I_______I

10 11 12 

NUMBER OF MAJOR SEPTA

13 14

FIGURE 18. Corallite diameter and number of major septa 

in Lithostrotion (Siphonodendron) dutroi n. sp. Each 

unnumbered symbol represents a single corallite; if 

more than one corallite shows the same diameter and 

number of septa, the number of similar corallites is 

shown.

and is characterized by the close corallite spacing of 

0.2-0.5 mm.

The only species within the Lisburne Group that 

remotely resembles L. (S.) dutroi n. sp. is Lithostrotion (Siphonodendron) lisburnensis n. sp., which 

has larger diameter corallites (1.5-2.8 mm) and
A18 CONTRIBUTIONS TO PALEONTOLOGY

10 mm

FIGURE 19. Sections of Lithostrotion (Siphonodendron) 

dutroi n. sp. (USNM 161085).

EXPLANATION

69A-1 + 1110A;USNM 160520; 

holotype

69A-1 + 1110B; USNM 160521; 

paratype

o

69A-1 + 1120; USNM 160522; 

paratype

10 11 12 13 14 15 16

NUMBER OF MAJOR SEPTA

17 18 19

FIGURE 20. Corallite diameter and number of major septa in 

Lithostrotion (Siphonodendron) ignekensis n. sp. Each 

unnumbered symbol represents a single corallite; if more 

than one corallite shows the same diameter and number of 

septa, the number of similar corallites is shown.

more major septa (11-16) (fig. 16). It is also characterized by corallites which are more widely 

spaced and tabulae that are more strongly arched 

toward the columella and then are reflexed to a 

lower angle near the dissepimentarium (fig. 17). 

The two species also appear to have different stratigraphic ranges. L. (S.) lisburnensis n. sp. is known

10 mm

FIGURE 21. Sections of Lithostrotion (Siphonodendron) ignekensis n. sp. (USNM 160520).

only from beds of latest Meramec (upper part of 

zone 15) and earliest Chester age (lower part of 

zone 16i), whereas L. (S.) dutroi n. sp. has been 

found in beds of middle and late Meramec age 

(zone 13 and lower part of 14).

Lithostrotion irregulare Phillips var. asiatica 

from China as described by Yabe and Hayasaka 

(1916, p. 57-60) and redescribed and illustrated by 

Yii (1933, p. 95-96) has relatively larger corallites 

with a diameter of 3.5 mm, 14-16 major septa, and 

a persistent single or a rare double row of dissepiments in the dissepimentarium. Furthermore, the 

Chinese species is distinguished from L. (S.) dutroi 

n. sp. by its shorter major septa, flatter tabulae, 

and occasionally diphymorphic corallites.

Lithostrotion junceum (Fleming) as redescribed 

by Hill (1940, p. 171-173, pi. 9, figs. 3-8) is somewhat similar to L. (S.) dutroi n. sp. but differs in a 

number of significant ways. It has a corallite diameter of 2.5-3.8 mm, 14-18 major and 14-18 short 

minor septa, and no dissepiments. Hill stated diphymorphic corallites may occur.

Dobroljubova (1958, p. 283, pi. 18, 19) described 

"narrow-tubed colonies" of Lithostrotion junceum 

(Fleming) from the Lower Carboniferous of the 

Russian Platform which have corallites with a diameter of 1.5-2 mm, 12-13 major septa, and no 

dissepiments; also, diphymorphic corallites are 

found within the corallum.

Easton's (1957, p. 616-622, pi. 71, figs. 5-12) 

species Lithostrotion (Siphonodendron) genevievensis, from late Meramec age rocks of the Ohio River 

valley, is distinguished from L. (S.) dutroi n. sp. 

by its large corallite diameter of 4.5 mm, typically 

16 thin major septa, and no minor septa. The species does contain a single row of dissepiments in the 

dissepimentarium.
MISSISSIPPIAN LITHOSTROTIONOID CORALS, LISBURNE GROUP, ALASKA A19

Name. The species is named in honor of J. 

Thomas Dutro, Jr., paleontologist and geologist, 

U.S. Geological Survey.

Lithostrotion (Siphonodendron) ignekensis n. sp.

Plate 5, figures 1-5

Material. Fragments of five colonies were collected from measured stratigraphic sections of the 

Alapah Limestone, Lisburne Group, northeastern 

Alaska. All specimens were studied in transverse 

and longitudinal thin sections. Three specimens 

from section 69A-1 have good preservation and are 

preserved by calcite (USNM 160520-160522). Specimen USNM 160523, from section 68A-3, was in 

part crushed before lithification. Specimen USNM 

160524, from section 68A-1, is from a tectonically 

stressed limestone and is distorted.

Description. The holotype, USNM 160520, is a 

fasciculate corallum. In transverse section, corallites 

have a spacing of 1-4 mm, a diameter of 2.9-5.2 

mm, and 14-17 long major septa (figs. 20, 21). 

Minor septa are generally developed as low ridges 

on the inside of the corallite wall and may extend 

0.2-0.4 mm into the dissepimentarium. The minor 

septa, commonly reappear on the axial side of the 

tabularium wall. Major septa are continuous 

through the dissepimentarium and taper from the 

periphery toward the axis of the corallite.

The columella is formed by the axial extensions 

of the counter septa (pi. 5, figs. 1, 4). In a number 

of corallites the counter and cardinal septa are continuous through the columella.

The corallite walls are approximately 200 microns 

thick and are formed by fibrous calcite, as are the 

major septa, which are 75-100 microns thick at 

their outer ends.

The preservation of the microstructure is good. 

The corallite walls are formed by dense fibrous calcite deposited normal to the exterior of the corallite. 

The septa are also made of fibrous calcite deposited 

nearly parallel to the length of the septa. The crystals of fibrous calcite are very small, less than 5 microns wide and not over 10 microns long. The dissepiments are composed of a denser, dark calcite; their 

wall thickness is 10-30 microns (pi. 5, figs. 1, 2).

In longitudinal section the holotype (pi. 5, fig. 3) 

has a dissepimentarium formed by one row of globose dissepiments (500-750 microns wide), of 

which there are 10-12 in a vertical distance of 10 

mm. The tabulae are nearly flat and abut against 

the dissepimentarium and columella at nearly 90°. 

The columella is persistent and slightly sinuous. 

Study of the microstructure of the columella and

the tabulae shows that the tabulae do not contribute 

to the structure of the columella (pi. 5, fig. 2).

Paratypes. Specimens USNM 160521 and 

160522 are similar in mode of preservation and 

morphology to the holotype except that the two paratypes have corallites with as many as 18 major 

septa (fig. 20).

Occurrence. The holotype was collected from the 

upper part of the Alapah Limestone, 1,120 feet 

above the base of section 69A-1 (figs. 13-15), at 

the west end of the Sadlerochit Mountains. The paratypes USNM 160521 and 160522 were collected 

1,110-1,120 feet above the base of the same section. 

The beds containing the corals have a small fauna 

of Foraminifera. Bernard L. Mamet (written commun., 1970) assigned a Chester-Morrow age (zones 

18-20) to the Foraminifera. A better foraminiferal 

fauna was found with the corals (Armstrong and 

others, 1970) collected from section 68A-3 (specimen USNM 160523). Here the microfauna indicates 

that the corals are Chester age (zones 17 and 18). 

Specimen USNM 160524, collected at 810 feet from 

the top of section 68A-1, in the Franklin Mountains, also occurs with a microfauna of Chester age 

(zones 17 and 18).

The microfaunal evidence reported by Armstrong, Mamet, and Dutro (1970) indicates that L. 

(S.) ignekensis n. sp. occurs in zones 17 and 18, of 

middle and late Chester age (fig. 13).

The species is known only from the upper part of 

the Alapah Limestone of northeastern Alaska. It 

has not been found in Chester age rocks of the central or western Brooks Range.

Remarks. Lithostrotion (Siphonodendron) genevievensis Easton (1957, p. 616-622, pi. 71, figs. 

5-12) from the Fredonia Oolite Member of the Ste. 

Genevieve Limestone of the Ohio River valley is 

similar to L. (S.) ignekensis is corallite diameter 

and number of major septa. L. (S.) ignekensis differs in having well-developed minor septa, less sinuous major septa, and flatter tabulae. In L. (S.) genevievensis the axial ends of the counter septa 

which form the columella are thicker, or swollen, in 

contrast to the more simple columella in L. (S.) ignekensis n. sp. In addition to the morphological differences between the two species, there is a significant stratigraphic separation. L. (S.) genevievensis 

Easton occurs in the late Meramec age Ste. Genevieve Limestone (zone 15), and L. (S.) ignekensis 

occurs in the Lisburne Group in rocks of Chester 

age (zones 17 and 18).
A20 CONTRIBUTIONS TO PALEONTOLOGY

Hill (1940) redescribed the European Lower Carboniferous species Lithostrotion (Siphonodendron) 

pauciradiale (McCoy), which has a similar corallite 

diameter and a higher number of major septa (22) 

but differs from L. (S.) ignekensis n. sp. primarily 

in having conical tabulae.

Hill (1940, p. 172) also redescribed Lithostrotion 

junceum (Fleming), which is similar to the Alaskan 

species but in which "dissepiments are never developed" and diphymorphic corallites may occur. These 

morphological characteristics have not been found 

in any colonies of L. (S.) ignekensis n. sp.

Lithostrotion volkovae Dobroljubova (1958, p. 

153-155, pi. 22, figs. 1, 2) from the Russian Platform is fasciculate and has corallites with diameters of 4-5 mm and 17-18 major septa. However, it 

differs from L. (S.) ignekensis n. sp. in a number 

of significant ways. It has a broad rounded or ellipsoidal columella, long minor septa, tabulae strongly 

arched to meet the columella, and a double row of 

dissepiments.

Lithostrotion (Siphonodendron) sinuosum (Warren, 1927), which is abundant in Meramec and 

Chester age (lower part of zone 16i) carbonates of 

the Lisburne Group, is similar in size and number of 

corallites to L. (S.) ignekensis. L. (S.) sinuosum 

(Warren) is readily recognized by its ellipsoidal 

columella, longer and thicker major and minor 

septa, and tabulae which are strongly arched to meet 

the columella (Armstrong, 1970b, fig. 12).

Name. L. (S.) ignekensis is derived from Ignek 

Creek, which flows between the Shublik and Sadlerochit Mountains into the Canning River. Ignek in 

Eskimo means "fire" (Orth, 1967, p. 445).

Genus DIPHYPHYLLUM Londsdale, 1845 

Diphyphyllum Lonsdale, 1845, in Murchison and others,

Geology of Russia and the Ural Mountains, v. 1, p. 622. 

Diphyphyllum Lonsdale. Thomson, 1883, Royal Philos. Soc.

Glasgow Proc., v. 10, p. 381. 

Diphyphyllum Lonsdale. Thomson, 1887, Geol. Soc. London

Quart. Jour., v. 43, p. 33. 

Lithostrotion Fleming, genomorph [Diphyphyllum Lonsdale].

Smith and Lang, 1930, Annals and Mag. Nat. History,

v. 5, p. 180.

Depasophyllum Yii, 1933, Palaeontologica Sinica, v. 12, p. 86. 

Lithostrotion Fleming, genomorph [Diphyphyllum Lonsdale].

Hill, 1940, Palaeontographical Soc., v. 94, p. 180-182. 

Diphyphyllum Lonsdale. Minato, 1955, Hokkaido Univ. Fac.

Sci. Jour., v. 9, no. 2, p. 80, 81. 

Diphyphyllum Lonsdale. Hill, 1956, in Moore, ed., Treatise on

invertebrate paleontology, Part F, Geol. Soc. America,

p. F283. 

Depasophyllum Yii. Minato and Kato, 1957, Hokkaido Univ.

Fac. Sci. Jour., ser. 4, v. 9, no. 4, p. 480.

Diphyphyllum Lonsdale. Dobroljubova, 1958, Akad. Nauk 

SSSR Paleont. Inst. Trudy, v. 70, p. 180-183.

Type species. Diphyphyllum concinnum Lonsdale, 1845, Carboniferous, Ural Mountains, 

U.S.S.R. Smith and Lang (1930, p. 180) state that 

the type D. concinnum is lost, and they base Diphyphyllum on D. lateseptatum McCoy, which, if 

not conspecific, is certainly congeneric with D. concinnum.

Diagnosis. Fasciculate corallum; columella undeveloped; septa continuous in dissepimentarium, amplexoid in tabularium; tabulae domed or flattened 

axilly, downturned peripherally (modified after 

Hill, 1965, p. F283).

Remarks. Smith (1928, p. 114) and later Hill 

(1940, p. 181) divided the species of Diphyphyllum 

into two groups on the basis of the structure of the 

tabulae. The majority of the described species of 

Diphyphyllum, including the type species, have 

inner tabulae which are strongly arched, and each 

arch rests upon the arch below. The smaller group 

comprises Diphyphyllum species that have complete 

tabulae with broad flat tops and downturned edges 

that extend to the dissepimentarium without touching the lower tabulae. Diphyphyllum venosum Armstrong and D. klaiuockensis Armstrong from the 

Mississippian of the west coast of Prince of Wales 

Island, southeastern Alaska, both belong to the latter, smaller group of the species, as does the new 

species from the Lisburne Group, D. nasorakensis.

Diphyphyllum nasorakensis n. sp.

Plate 6, figures 1-6; plate 7, figures 1-6

Material. The four specimens available for 

study were collected by J. T. Dutro, Jr., and myself 

from carefully measured and sampled stratigraphic 

sections. All specimens are fragments of coralla. 

The specimens are preserved in blocks or beds of 

limestone, and the exterior of the corallites or coralla was not available for study. The size of the 

fragments of each colony is approximately:

USNM 161044, holotype ________ 20X25X25 cm

USNM 161045, paratype ________ 15X15X15 cm

USNM 161047, paratype ________ 8 X 9 X10 cm

USNM 161068, paratype _______ 6X7x7 cm

Several transverse and longitudinal 2- by 3-inch 

thin sections were cut of each corallum. A number 

of polished slabs were made, and these were studied by reflected light. Specimens USNM 161046 

and 161069 have badly crushed corallites, and measurements of diameter and septa cannot be made.

Description. The holotype, USNM 161044 (pi.
MISSISSIPPIAN LITHOSTROTIONOID CORALS, LISBURNE GROUP, ALASKA A21

14

13

£ 12

LlJ 

LlJ

1 11

^

i

^ 10-

EXPLANATION

68A-9 + 236; USNM 161044 

holotype

68A-9 + 238; 

USNM 161045

68A-9 + 258; 

USNM 161047

68A-13+14B; 

USNM 161068

20 21 22 23 24 25 26

NUMBER OF MAJOR SEPTA

27 28

FIGURE 22. Corallite diameter and number of major septa 

in Diphyphyllum nasorakensis n. sp. Each unnumbered 

symbol represents a single corallite; if more than one 

corallite shows the same diameter and number of septa, 

the number of similar corallites is shown.

10 mm

FIGURE 23. Sections of Diphyphyllum nasorakensis n. sp. 

(USNM 161044).

6, figs. 1-6), is a fasciculate corallum. Spacing between corallites is typically 2-5 mm but may range 

from 0.5 to 12 mm. In transverse section the corallites are 7.9-13.1 mm in diameter and have 23-27 

major septa (figs. 22, 23). The major septa are 

short, 0.8-1.2 mm in length, and 100-150 microns 

thick at their outer ends. The corallite wall is 

100-200 microns thick. The majority of corallites 

are devoid of minor septa; where present, the minor

septa are 0.2-0.3 mm long and 50-70 microns thick 

at their outer ends. The corallite walls and septa 

appear to be composed of a mosaic of calcite crystals 10 microns or less in size. The microstructure is 

poorly preserved, having been affected by calcite recrystallization, grain growth, and selective silicification of internal structures. Petrographic studies 

reveal that the corallite walls are composed of an 

outer, dark layer, approximately 20 microns thick, 

formed by interlocking calcite crystals 5 microns in 

size. The inner part of the corallite walls is 60-120 

microns thick and is formed by dense fibrous to 

granular calcite. The septa appear to be made of fibrous calcite deposited nearly parallel to the length 

of the septa, although they are now commonly granular calcite (recrystallized) or are replaced by chalcedony (pi. 6, figs. 4-6). The corallites are acolumellate.

In general the major septa are continuous 

throughout the dissepimentarium except in some 

specimens where the dissepimentarium may widen 

in a parent corallite adjacent to an offset (fig. 23).

Longitudinal sections of the corallites show the 

tabulae to be complete; they are flat to very gently 

convex upward. At a distance of 1-1.5 mm from 

the corallite walls the tabulae are reflexed downward at angles of 20°-45° from the horizontal. 

Generally a single row of dissepiments is present, 

but the dissepiments are commonly discontinuous. 

Dissepiments are 0.2-0.5 mm wide and 0.5-1.3 mm 

long. The walls of the tabulae and dissepiments are 

40-70 microns thick and are composed of crystals 

of calcite 5-15 microns in size.

Paratypes USNM 161045, 161047, and 161068 

are, except for a slightly smaller corallite diameter, 

similar in all respects to the holotype. All specimens 

are acolumellate.

Occurrence. Diphyphyllum nasorakensis n. sp. 

was found south of Cape Lewis in the Nasorak Formation, Lisburne Group (figs. 7, 9), at 236 feet 

above the base of section 68A-9 (USNM 161044), 

at 238 feet (USNM 161045), and at 241 feet 

(USNM 161047). The foraminiferal fauna in these 

beds is earliest Chester in age (zone 16i) (Armstrong and others, 1971), and the coral fauna consists of the following species: Lithostrotion (Siphonodendron) lisburnensis n. sp., L. (S.) sinuosum 

(Kelly), L. (S.) warreni Nelson, and Lithostrotionella banffensis (Warren).

The two specimens collected from the Lisburne 

Group south of Niak Creek, section 68A-13 (figs. 3, 

5), were from 14 feet (USNM 161068) and 103 feet
A22 CONTRIBUTIONS TO PALEONTOLOGY

(USNM 161069) above the base of the section. The 

foraminiferal fauna from these beds, according to 

Armstrong, Mamet, and Dutro (1971), is latest 

Meramec (upper part of zone 15) and earliest Chester (zone 16i) age. In addition to the associated 

coral species found with D. nasorakensis in section 

68A-9, Lithostrotionella birdi Armstrong, L. mclareni (Sutherland), Thyscmophyllum astraeiforme 

(Warren), Sciophyllum lambarti Harker and McLaren, and S. alaskaenis Armstrong have been 

found in section 68A-13.

The known range of D. nasorakensis is latest 

Meramec (boundary between zones 15 and 16i) and 

earliest Chester (zone 16i).

Coral collections made by Armstrong (1970b) 

from the Meramec and possibly early Chester age 

parts of the Kogruk Formation in the DeLong 

Mountains do not have any forms which could be 

referred to the genus Diphyphyllum. This genus is 

also absent from my collections of Meramec and 

Chester age coral faunas from the Lisburne Group 

in the Endicott Mountains.

Diphyphyllum nasorakensis n. sp. has not been 

found in the Lisburne Group in the Franklin or Romanzof Mountains, northeastern Alaska. The stratigraphic range of the very closely related species D. 

klawockensis Armstrong appears to be somewhat 

older; this species is abundant in beds of Meramec 

age (primarily in zones 13 and 14).

The type specimen of D. klawockensis Armstrong 

(1970a) from the limestone and chert member of 

the Peratrovich Formation, Prince of Wales Island, 

southeastern Alaska, is found in beds which contain 

a large foraminiferal fauna of Meramec (zones 13 

and 14) age in association with D. venosum Armstrong, Lithostrotionella banffensis (Warren), L. 

pennsylvanica (Shinier), L. birdi Armstrong, Thysanophyllum astraeiforme (Warren), and Sciophyllum alaskaensis Armstrong.

Diphyphyllum klawockensis has been found in the 

Lisburne Group at 45 feet above the base of the 

South Cape Lewis section (68A-9) (figs. 7, 9) in 

beds of earliest Chester age (zone 16i). D. klawockensis is common in Meramec (zones 13 and 14) beds 

of the Kayak (?) Shale and the Lisburne Group of 

the Franklin and Romanzof Mountains of northeastern Alaska.

Remarks. The examples of Diphyphyllum nasorakensis n. sp. from the Lisburne Group at Cape 

Lewis and south of Niak Creek differ from the type 

material of D. klawockensis Armstrong (1970a) 

from the Peratrovich Formation, Prince of Wales 

Island, southeastern Alaska, in having very few

minor septa between the major septa. The holotype 

and the paratypes of D. klawockensis Armstrong 

(1970a, pi. 5, figs. 2-6) are characterized by having 

0.3-mm-long minor septa between the major septa. 

Except for the slightly shorter major septa and the 

diminutive to absent minor septa, D. nasorakensis 

is very similar morphologically to D. klawockensis 

Armstrong.

Diphyphyllum venosum Armstrong (1970a, pi. 6, 

figs. 1-7, and pi. 9, figs. 4, 5) from the Meramec 

age beds of the Peratrovich Formation, Prince of 

Wales Island, southeastern Alaska, is distinguished 

from D. nasorakensis and D. klawockensis by its 

larger corallite diameter of 10-12 mm, 25-34 

major septa, and three or four rows of dissepiments.

Diphyphyllum furcatum Thomson from the Visean of Scotland as described by Hill (1940, p. 

185-186) is similar in corallite diameter and in 

number and length of major septa to D. klawockensis. D. furcatum differs in having two or three rows 

of dissepiments and in having tabulae which are in 

two series, an inner series consisting of very broad, 

flattened domes whose downturned edges abut on 

the lower dome and an outer series that is narrow 

and consists of small concave plates (Hill, 1940, pi. 

11, fig. 1).

Diphyphyllum vermiculare (Stuckenberg) as described by Dobroljubova (1958, p. 195-197, pi. 33, 

fig. 3) is similar in corallite diameter and in number and development of septa to D. klawockensis. 

The Russian species differs in having (p. 195) "trapeziform tabulae which make contact with the underlying tabulae or with the dissepiments" and in 

having one to three rows of dissepiments.

Name. D. nasorakensis refers to the Nasorak 

Formation (Campbell, 1967), from which the type 

material was collected.

Family LONSDALEIIDAE Chapman, 1893 

Genus LITHOSTROTIONELLA Yabe and Hayasaka, 1915

Lithostrotionella Yabe and Hayasaka, 1915, Geol. Soc. Tokyo

Jour., v. 22, p. 94. 

Lithostrotionella Yabe and Hayasaka. Hayasaka, 1936,

Taihoku Imp. Univ., Formosa, v. 13, no. 5, p. 47-58. 

Lithostrotionella Yabe and Hayasaka. Hill, 1956, in Moore,

ed., Treatise on invertebrate paleontology, Part F, Geol.

Soc. America, p. F306-307.

Type species. Lithostrotionella unicum Yabe and 

Hayasaka, 1915, Permian, Chihsia Limestone, Yunnan, South China.

Diagnosis. Cerioid corallum; prismatic corallites; columella a persistent vertical lath frequently 

continuous with counter and cardinal septa; lonsda-
MISSISSIPPIAN LITHOSTROTIONOID CORALS, LISBURNE GROUP, ALASKA A23

leoid dissepiments; major septa intermittently reach 

wall along tops of dissepiments; minor septa short; 

tabulae commonly complete, conical. (Summarized 

from Yabe and Hayasaka, 1915, p. 94.)

Lithostrotionella niakensis n. sp.

Plate 4, figures 2, 6; plate 8, figures 1-3;

plate 9, figures 1-6

Lithostrotionella sp. A. Armstrong, 1970b, U.S. Geol. Survey 

Prof. Paper 664, p. 25, 26, pi. 7, figs. 1-6.

Material. The five speciments available for 

study were collected by J. Thomas Dutro, Jr., and 

myself from measured stratigraphic sections. The 

specimens are preserved in blocks of limestone, and 

the exterior of the coralla cannot be seen. All specimens are fragments of coralla. The approximate 

size of each fragment is:

USNM 161074 ______________ 7X7X7 cm 

USNM 161075 (badly broken) ____ 7 X 7 X12 cm 

USNM 161076 _______________ 9X10X12 cm 

USNM 161077 ______________ 4X10X10 cm 

USNM 161078 ______________ 4X8X9 cm

A transverse and a longitudinal 2- by 3-inch thin 

section were cut of each corallum. About 100 corallites per corallum were studied in thin section.

Description. The holotype, USNM 161074 (pi. 

4, figs. 2, 6; pi. 8, fig. 3; pi. 9, figs. 5, 6), is a cerioid 

corallum and in transverse section has prismatic 

corallites that are typically 2.5-3.5 mm in diameter 

and have 11-14 major septa (figs. 24, 25). In some 

corallites the major septa are 1-1.5 mm long, and 

the minor septa are 0.5-0.7 mm long. The major 

septa are generally continuous through the dissepimentarium. In the larger corallites, which have a 

columella and a diameter in excess of 3.5 mm, the 

dissepiments are generally lonsdaleoid and may intercept the loci of the majority of the major septa. 

Except for the cardinal and counter septa, which 

may reach the columella, the major septa are withdrawn from the axial region. Serial transverse thin 

sections reveal that the corallites are acolumellate 

at various levels, and typically the major septa extend i/4-% the distance to the axial region as short 

ridges on the upper surfaces of the tabulae. Where 

the columella is well developed, the major septa 

commonly extend into the axial region and may 

even reach the columella. The weaker the development of the columella, the more amplexoid are the 

septa. In acolumellate corallites the major septa extend only a short distance beyond the tabularium 

wall into the axial region (fig. 25).

Transverse sections show the dissepimentarium 

to be present throughout the length of the corallite 

and to be formed by a single row, and in some specEXPLANATION

A

68A-12 + 700A; USNM 161078

o 

68A-12 + 700E; USNM 161075

4 -

t 3

I I I I 

EXPLANATION

68A-12 + 700B; holotype; USNM 161074

A

68A-12 + 700T; USNM 161076 

68A-12+725C; USNM 161077

10 11 12 13 

NUMBER OF MAJOR SEPTA

14 15

FIGURE 24. Corallite diameter and number of major septa 

in Lithostrotionella niakensis n. sp. Each unnumbered 

symbol represents a single corallite; if more than one 

corallite shows the same diameter and number of septa, 

the number of similar corallites is shown.

imens a double row, of globose dissepiments, of 

which nine to 11 occur in 5 mm. The dissepimentarium is 0.5-0.9 mm wide. The columella may be 

well developed at certain levels and absent at other 

levels of the corallite. Where the columella is well 

developed, the dissepimentarium tends to be formed 

by two rows of dissepiments, and the tabulae are 

complete. The tabulae are nearly horizontal to a
A24 CONTRIBUTIONS TO PALEONTOLOGY

10 mm

FIGURE 25. Sections of Lithostrotionella niakensis n. sp. 

(USNM 161074).

distance of 0.5-0.7 mm from the columella, and then 

they are reflexed downward at angles of 45°-65° 

from the horizontal. The tabulae are reflexed at a 

lower angle before reaching the dissepiments (pi. 4, 

fig. 2; pi. 9, fig. 6). In acolumellate corallites the 

tabulae are complete and dome shaped (pi. 9, fig. 

5).

The corallite wall in transverse section is 

100-150 microns thick, and its center is marked by 

a dark calcite band 30 microns thick (pi. 4, figs. 2, 

6). The corallite wall is composed of fibrous calcite 

deposited normal to this dark band. The microstructure of the septa is fibrous calcite deposited at angles at 20°-25° from the axis of the septum. In longitudinal section, the tabulae and dissepiment walls 

are 30 microns thick, and their microstructure is a 

mosaic of crystals of calcite 5-10 microns in size.

Paratype USNM 161077 (pi. 8, figs. 1, 2) differs 

from the holotype in having a corallite diameter of 

2.5-3.8 mm and 12-14 major septa. Furthermore, 

some of the corallites are characterized by a very 

massive and thick columella and by major septa 

that are long and commonly extend to and join the 

columella. Adjacent corallites may have a columella 

which is less massive, and some corallites are diphymorphic.

Paratypes USNM 161075, 161076, and 161078 are 

all from the same bed (fig. 4) and do not differ in 

any significant morphological characteristics from 

the holotype (fig. 24).

Occurrence. The type material for Lithostrotionella niakensis was collected north of Niak Creek 

in the Lisburne Group, at 700 feet below the top of 

section 68A-12 (figs. 3, 4) (USNM 161074, 161075,

161076, 161078) and at 725 feet below the top of 

this section (USNM 161077). Armstrong, Mamet, 

and Dutro (1971) reported that the associated Foraminifera indicate a middle Meramec age (zone 13). 

The Foraminifera are archaediscids, Archaediscus 

of the group A. krestovnikovi Rauzer-Chernoussova; endothyrids, Eoendothyranopsis of the group 

E. pressa Grozdilova, in Lebedeva, and Globoendothyra sp.; eoforschiids, Eoforschia; and primitive 

bradyinids, Endothyranopsis. The associated coral 

fauna consists of Lithostrotion (Siphonodendron) 

warreni Nelson and Lithostrotionella banffensis 

(Warren).

Lithostrotionella sp. A described by Armstrong 

(1970b, p. 25) is assigned to the species L. niakensis. It was collected from the Kogruk Formation in 

a river cutbank of the Kukpuk River in the Lisburne Hills region, where it was found in association with a foraminiferal and coral fauna of Meramec age.

Present knowledge of the stratigraphic 

distribution of L. niakensis suggests that the species is characteristic of rocks of Meramec age 

(zones 13 and 14) within the Lisburne Group.

Remarks. Lithostrotionella mclareni (Sutherland) is similar in corallite diameter and in number 

of major septa to L. niakensis but differs in having 

major septa that are better developed and thicker 

and that tend to be dilated in the tabularium, and 

in having few corallites in which the septa are well 

developed within the dissepimentarium. Further, if 

the columella is weakly developed or absent, then 

the septa are more strongly amplexoid, the dissepiments tend to be strongly lonsdaleoid, and the septa 

are very poorly developed or absent in the dissepimentarium. In contrast, L. niakensis, in acolumellate sections of the corallites, generally has major 

septa that are relatively well developed and persistent in the dissepimentarium. In L. niakensis those 

sections of a corallite which contain a columella have 

tabulae that are complete and horizontal and are not 

bent or arched to join the columella. L. mclareni, 

however, has strongly arched tabulae which are 

more sharply bent upward before joining the columella.

The syntype of the Meramec age Lithostrotionella 

macouni (Lambe) as redescribed by Nelson (1960) 

and Armstrong (1970b) differs from L. niakensis n. 

sp. in having corallites with a diameter of 2-3 mm 

and 9 to 11 major septa. The major septa are long 

and commonly join the columella. The tabulae may 

be complete or incomplete and are arched to meet 

the columella.
MISSISSIPPIAN LITHOSTROTIONOID CORALS, LISBURNE GROUP, ALASKA A25

Lithostrotion trimorphum Groot (1963, p. 49-51, 

pi. 6, figs. 1, 2) from the Perapertu Formation of 

Palencia, Spain, is similar in size and number of 

corallites to L. niakensis n. sp. The Spanish species 

has wide variation in the morphology of the corallites and displays within a single corallum the 

traits of the genera Lithostrotion, Lithostrotionella, and Thysanophyllum. Although it is morphologically very similar to L. niakensis, L. trimorphum differs in having corallites with a persistent 

columella and slightly arched and domed tabulae. In 

addition, the dissepimentarium is somewhat wider 

and has a stronger trend toward the development of 

a double row of dissepiments.

Name. L. niakensis is from Niak Creek south of 

the collection locality. According to Orth (1967, p. 

685), Niak may mean "head" in Eskimo.

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Armstrong, A. K., 1970a, Mississippian rugose corals, 

Peratrovich Formation, west coast of Prince of Wales 

Island, southeastern Alaska: U.S. Geol. Survey Prof. 

Paper 534, 43 p., 13 pis., 30 figs.

 1970b, Carbonate facies and the lithostrotionoid corals 

of the Mississippian Kogruk Formation, DeLong Mountains, northwestern Alaska: U.S. Geol. Survey Prof. 

Paper 664, 38 p., 14 pis., 37 figs.

Armstrong, A. K., and Mamet, B. L., 1970, Biostratigraphy 

and dolomite porosity trends of the Lisburne Group, in 

Adkison, W. L., and Brosge, M. M., eds., Proceedings of 

the geological seminar on the North Slope of Alaska: 

Los Angeles, Pacific Sec. Am. Assoc. Petroleum Geologists, p. N1-N16, 12 figs.

Armstrong, A. K., Mamet, B. L., and Dutro, J. T., Jr., 1970, 

Foraminiferal zonation and carbonate facies of Carboniferous (Mississippian and Pennsylvanian) Lisburne 

Group, central and eastern Brooks Range, Arctic Alaska: 

Am. Assoc. Petroleum Geologists Bull., v. 54, no. 5, p. 

687-698, 4 figs.

 1971, Lisburne Group, Cape Lewis-Niak Creek, northwestern Alaska, in Geological Survey research 1971: U.S. 

Geol. Survey Prof. Paper. 750-B, p. B23-B34.

Bowsher, A. L., and Dutro, J. T., Jr., 1957, The Paleozoic 

section in the Shainin Lake area, central Brooks Range, 

Alaska: U.S. Geol. Survey Prof. Paper 303-A, p. 1-39, 

6 pis., 4 figs.

Campbell, R. H., 1967, Areal geology in the vicinity of the 

Chariot site, Lisburne Peninsula, northwestern Alaska: 

U.S. Geol. Survey Prof. Paper 395, 71 p., 1 pi., 28 figs.

Dobroljubova, T. A., 1958, Nizhnekamennogol'nye koloniaPnye chetyrekhluchevye korally Russkoi platformy [Lower 

Carboniferous colonial tetracorals of the Russian Platform]: Akad. Nauk SSSR Paleont. Inst. Trudy, v. 70, 

216 p., 38 pis., 34 figs.

Easton, W. H., 1957, On the tetracoral Lithostrotion harmodites Milne-Edwards and Haime: Jour. Paleontology, 

v. 31, no. 3, p. 616-622, pi. 71.

Groot, G. E. de, 1963, Rugose corals from the Carboniferous 

of northern Palencia (Spain): Leidse Geol. Mededel., 

pt. 29, 123 p., 26 pis., 39 figs.

Hill, Dorothy, 1938-41, A monograph on the Carboniferous 

rugose corals of Scotland: Palaeontographical Soc. 

[London], 1938, pt. 1, p. 1-78 (v. 91), 2 pis., 2 figs.; 1939, 

pt. 2, p. 79-114 (v. 92), 3 pis.; 1940, pt. 3, p. 115-204 

(v. 94); 1941, pt. 4, p. 205-213 (v. 95).

 1956, Rugosa, in Moore, R. C., ed., Treatise on invertebrate paleontology, Part F, Coelenterata: Geol. Soc. 

America and Kansas Univ. Press, p. F233-F324.

Kato, Makoto, 1963, Fine skeletal structures in rugose: 

Hokkaido Univ. Fac. Sci. Jour., ser. 4, v. 11, no. 4, p. 

571-630, 3 pis., 19 text figs.

Kelly, W. A., 1942, Lithostrotiontidae in the Rocky Mountains: 

Jour. Paleontology, v. 16, no. 3, p. 351-361, pis. 50 and 51, 

1 text fig.

Macqueen, R. W., and Bamber, E. W., 1968, Stratigraphy and 

facies relationships of the Upper Mississippian Mount 

Head Formation, Rocky Mountains and foothills, southwestern Alberta: Bull. Canadian Petroleum Geology, v. 

16, no. 3, p. 225-287, 11 figs.

Nelson, S. J., 1960, Mississippian lithostrotionid zones of the 

southern Canadian Rocky Mountains: Jour. Paleontology, 

v. 34, no. 1, p. 107-125, pis. 21-25, 3 text figs.

Oliver, W. A., 1968, Some aspects of colony development in 

corals, in Paleobiological aspects of growth and development A symposium: Paleont. Soc. Mem. 2, Jour. Paleontology, v. 42, no. 5, supp. p. 16-34, 6 figs.

Orth, D. J., 1967, Dictionary of Alaska place names: U.S. 

Geol. Survey Prof. Paper 567, 1084 p.

Sable, E. G., and Dutro, J. T., Jr., 1961, New Devonian and 

Mississippian Formations in DeLong Mountains, northern Alaska: Am. Assoc. Petroleum Geologists Bull., v. 45, 

no. 5, p. 585-593, 4 figs.

Sando, W. J., Mamet, B. L., and Dutro, J. T., Jr., 1969, 

Carboniferous megafaunal and microfaunal zonation in 

the northern Cordillera of the United States: U.S. Geol. 

Survey Prof. Paper 613-E, 29 p., 7 figs.

Smith, Stanley, 1928, The Carboniferous coral Nemistium 

edmondsi gen. et sp. n.: Annals and Mag. Nat. History, 

ser. 10, v. 1, p. 112-120, 1 pi.

Smith, Stanley, and Lang, W. D., 1930, Description of the 

type-specimens of some Carboniferous corals of the genera 

"Diphyphyllum," "Stylastracea" Aulophyllum and Chaetetes: Annals and Mag. Nat. History, ser. 10, v. 5, no. 

26, p. 177-194, 2 pis.

Warren, P. S., 1927, Banff area, Alberta: Canada Geol. 

Survey Mem. 153, 94 p., 7 pis.

Yabe, Hisakatsu, and Hayasaka, Ichiro, 1915, Palaeozoic 

corals from Japan, Korea, and China: Geol. Soc. Tokyo 

Jour., v. 22, no. 264, p. 93-109.

 1916, Palaeozoic corals from Japan, Korea, and China: 

Geol. Soc. Tokyo Jour., v. 23, no. 271, p. 57-62.

Yii, C. C., 1933, Lower Carboniferous corals of China: China 

Geol. Survey, Palaeontologica Sinica, ser. B, v. 12, pt. 3, 

211 p., 24 pis.

 1937, The Fenginian corals of south China: Acad. 

Sinica, Inst. Geology and Paleontology, Chi-K'an Mem., 

no. 16, 111 p., 13 pis.

INDEX

[Italic page numbers indicate both major references and descriptions] 

Page Page

alaskaensis, Sciophyllum .......... Al,

9, 11,22 

Anthozoa ..................... 9

Archaediscus ................... 24

krestovnikovi ................ 24

asiatica, Lithostrotion

irregulare ............ .13, 18

Lithostrotion (Siphonodendron) irregularis ........ 13

astraeiforme, Thysanophyllum ..... 1,9,

16, 22

banffensis, Lithostrotionella ....... 1,9,

11, 16,21,24 

Biostratigraphic distribution

of Lisburne Group lithostrotionoid corals ....... 6

birdi, Lithostrotionella ........... 1,

9,22

Coelenterata ...........

concinnum, Diphyphyllum

9

20

Depasophyllum ................. 20

Diphyphyllum ................ .20, 22

concinnum .................. 20

furcatum ................... 22

klawockensis ................ 9,

20, 22 

lateseptatum ................ 19

nasorakensis ................. 11,

20; pi. 6, 7 

venosum .................. .20, 22

vermiculare ................. 22

dutroi, Lithostrotion (Siphonodendron) ............ 2,

14; pi. 3,4

Endothyranopsis . .

Eoendothyranopsis

pressa ........

Eoforschia ......

furcatum, Diphyphyllum

24

24

24

24

22

genevievensis, Lithostrotion 

(Siphonodendron)

Globoendothyra

. 13,

18, 19

24

ignekensis, Lithostrotion

(Siphonodendron) ...... 6,

14, 19; pi. 5 

Introduction ................... 1

irregulare asiatica, Lithostrotion . . . .13, 18

irregularis asiatica, Lithostrotion

(Siphonodendron) ...... 13

junceum, Lithostrotion ........... A12,

18,20

klawockensis, Diphyphyllum 

krestovnikovi, Archaediscus 

lambarti, Sciophyllum ....

9,

20,22

24

1, 

11, 22 

lateseptatum, Diphyphyllum ...... 19

lisburnensis, Lithostrotion

(Siphonodendron) ...... 10,

18, 21; pi. 1, 2 

Lithostrotion .................. 9,

20,25 

irregulare asiatica ............ .13, 18

junceum .................... 12,

18,20 

pauciradialis ................. 10

striatum .................... 9

trimorphum ................. 25

volkovae ................... 20

(Siphonodendron) ............ 17

dutroi ................... 2,

14; pi. 3, 4 

genevievensis .............. 13,

18, 19 

ignekensis ................ 6,

14, 19; pi. 5 

irregularis asiatica .......... 13

lisburnensis ............... 10,

18, 21; pi. 1, 2 

pauciradiale .............. 20

sinuosum ................ 1,

11, 14, 20, 21 

warreni .................. 1,9,

11, 16, 21,24 

sp. A .................... 1

spp ..................... 5

Lithostrotionella ................ 6,

22. 25 

banffensis .................. 1,9,

11, 16, 21,24 

birdi ....................... 1,

9, 22 

lochmanae .................. 6

macouni .................... 24

mclareni .................... 1,9,

16, 22, 24 

micro ...................... 6

microstylum ................ 6

niakensis ................... 23;

pi. 4, 8,9 

pennsylvanica ............... 22

unicum .................... 22

sp. A ...................... 1,

23. 24 

sp.B ...................... 1

Lithostrotionidae ........

lochmanae, Lithostrotionella 

Lonsdaleiidae ...........

Page

A9

6

22

macouni, Lithostrotionella ........ 24

mclareni, Lithostrotionella ........ 1,9,

16, 22, 24 

micro, Lithostrotionella .......... 6

microstylum, Lithostrotionella ..... 6

nasorakensis, Diphyphyllum ....... 11,

20; pi. 6, 7 

niakensis, Lithostrotionella ........ 23;

pi. 4, 8,9 

North Niak Creek section ......... 2

orientale, Thysanophyllum

pauciradiale, Lithostrotion

(Siphonodendron) ...... 20

pauciradialis, Lithostrotion ........ 10

pennsylvanica, Lithostrotionella .... 22

pressa, Eoendothyranopsis ........ 24

References cited 

Rugosa ......

25

9

Sciophyllum alaskaensis .......... 1,9,

11, 22 

lambarti .................... 1,

11,22 

sp.A ...................... 1

sp ......................... 16

sinuosum, Lithostrotion

(Siphonodendron) ...... 1,

11,14,20 

Siphonodendron ................ 10

(Siphonodendron), Lithostrotion ... 17 

dutroi, Lithostrotion .......... 2

14; pi. 3, 4 

genevievensis, Lithostrotion ..... 13,

18, 19 

ignekensis, Lithostrotion ....... 6,

14, 19; pi. 5 

irregularis asiatica,

Lithostrotion .......... 13

lisburnensis, Lithostrotion ...... 10,

18, 21; pi. 1,2 

pauciradiale, Lithostrotion ..... 20

sinuosum, Lithostrotion ....... 1,

11, 14,20 

warreni, Lithostrotion ......... 1,9,

11, 16,21,24 

South Cape Lewis section ......... 5

South Niak Creek section ......... 2

Stratigraphic sections ............ 2

striatum, Lithostrotion ........... 9

A27
A28 INDEX

orientate .............

Page 

..... A5

..... 9

..... 25

1 Q

16, 22 

..... 1 venosum. DinhyDhyllum ......

Page

A 1

. . . . 25

99

. . . .20. 22

Page

vermiculare, Diphyphyllum ....... A22

volkovae, Lithostrotion .......... 20

warreni, Lithostrotion

(Siphonodendron) ...... 1,9,

11, 16, 21, 24 

West Sadlerochit Mountains

section ............... 5
PLATES 1-9

Contact prints of each fossil plate in this publication are available at cost from the Library, U.S. Geological Survey, Federal

Center, Denver, Colorado 80225.
PLATE 1

FIGURE 1-5. Lithostrotion (Siphonodendron) lisburnensis n. sp. Nasorak Formation, south Niak Creek section, 68A-13.

1-4. 1, Longitudinal thin section (X 9). 2, Transverse photomicrograph (X 25), illustrating microstructure

and preservation. Corallite and matrix are preserved by calcite, except for chalcedony replacement in parts

of the corallite wall and adjacent dissepimentarium; arrow points to a small area replaced by chalcedony.

3, Longitudinal photomicrograph (X 25), showing dark granular calcite of the dissepiments and the very

thin tabulae. 4, Transverse thin section (X 9). Holotype, USNM 161064. 

5. Longitudinal thin section (X 4). Paratype, USNM 161065.
GEOLOGICAL SURVEY PROFESSIONAL PAPER 743-A PLATE 1

LITHOSTROTION (SIPHONODENDRON) LISBURNENSIS N. SP.
PLATE 2

FIGURES 1-7. Lithostrotion (Siphonodendron) lisbumensis n. sp., south Cape Lewis section, 68A-9.

1,7. 1, Transverse; 7, longitudinal oblique thin section (X 4). Paratype, USNM 161052. 

2,3. 2, Transverse; 3, longitudinal thin section (X 4). Paratype, USNM 161061.

4. 6. 4, Longitudinal; 6, transverse thin section (X 4). Paratype, USNM 161053.

5. Transverse thin section ( X 4) ; matrix surrounding corallite is extensively replaced by chalcedony. Paratype, USNM 161056.
GEOLOGICAL SURVEY PROFESSIONAL PAPER 743-A PLATE 2

LITHOSTROTION (SIPHONODENDRON) LISBURNENSIS N. SP.
PLATE 3

FIGURES 1-7. Lithostrotion (Siphonodendron) dutroi n. sp. Holotype, USNM 161085, 185 feet above the base of the Alapah

Limestone, type section, Shainin Lake, Alaska. 

1,2, 6. Transverse photomicrographs (X 25), illustrating microstructure; corallites and matrix are preserved

by calcite; figure 2 shows the dark outer band on the corallite wall. 

3, 4. Longitudinal thin sections ( X 15).

5. Longitudinal photomicrograph (X 25), illustrating the dark wall structure and dissepiments. 

7. Transverse thin section (X 15).
GEOLOGICAL SURVEY PROFESSIONAL PAPER 743-A PLATE 3

LITHOSTROTION (SIPHONODENDRON) DUTROI N. SP.
PLATE 4

FIGURES 1, 3-5. Lithostrotion (Siphonodendron) dutroi n. sp. Alapah Limestone, west fork Hulahula River. 

1,4. 1, Transverse; 4, longitudinal thin section (X 4). Paratype, USNM 161090. 

3,5. 3, Longitudinal; 5, transverse thin section (X 4). Paratype, USNM 161087. 

2, 6. Lithostrotionella niakensis n. sp. Holotype, USNM 161074, Kogruk Formation, north Niak Creek section,

68A-12. 

2. Longitudinal photomicrograph (X 25), illustrating the fibrous microstructure of the columella and corallite wall; dark central band in the corallite wall is shown. T, tabulae; C, columella; D, dissepiments; W,

wall; S, septa. 

6. Transverse photomicrograph (X 25), illustrating the fibrous microstructure of the corallite walls with

their dark central band, and the granular microstructure of the tabulae and dissepiments.
GEOLOGICAL SURVEY PROFESSIONAL PAPER 743-A PLATE 4

LITHOSTROTION (SIPHONODENDRON) DUTROI N. SP. AND 

LITHOSTROTIONELLA NIAKENSIS N. SP.
PLATE 5

FIGURES 1-5. Lithostrotion (Siphonodendron) ignekensis n. sp. Holotype, USNM 160520, Alapah Limestone, west Sadlerochit 

Mountains section, 69A-1.

1, 2. 1, Transverse photomicrograph ( X 25), illustrating microstructure of the wall, major septa, long counter 

septum, and columella. The darker color and texture of the dissepiments and tabulae are in contrast to 

the microstructure of the septa and wall. 2, Longitudinal photomicrograph (X 25); T, tabulae; C, columella; D, dissepiment. Microstructure of the columella and corallite wall contrasting with that of the dissepiments and tabulae is shown.

3-5. 3, Longitudinal; 4, transverse thin section (X 9); 5, transverse thin section (X 4).
GEOLOGICAL SURVEY PROFESSIONAL PAPER 743-A PLATE 5

LITHOSTROTION (SIPHONODENDRON) IGNEKENSIS N. SP.
PLATE 6

FIGURES 1-6. Diphyphyllum nasorakensis n. sp. Holotype, USNM 161044, Nasorak Formation, south Cape Lewis section, 

68A-9.

1-3. 1, Longitudinal; 2, 3, transverse thin sections (X 3).

4-6. 4, Longitudinal; 5, 6, transverse photomicrographs (X 25), illustrating wall structure and preservation; 

the matrix and most of the corallum and interior is calcite, although most areas near the corallite walls 

have been selectively silicified. Arrows point to locations where chalcedony has penetrated the walls, septa, 

and dissepiments. Figure 4 shows where chalcedony has selectively destroyed much of the tabulae.
GEOLOGICAL SURVEY PROFESSIONAL PAPER 743-A PLATE 6

^ '&gw? -.v.^r

^k&^\l%^«

DIPHYPHYLLUM NASORAKENSIS N. SP.
PLATE 7

FIGURES 1-6. Diphyphyllum nasorakensis n. sp. Nasorak Formation, south Cape Lewis section, 68A-9.

1-3,6. 1, 6, Transverse; 2, 3, longitudinal thin sections (X 3). Paratype, USNM 161045. 

4,5. 4, Longitudinal; 5, transverse thin section (X 3). Paratype, USNM 161047.
GEOLOGICAL SURVEY PROFESSIONAL PAPER 743-A PLATE 7

DIPHYPHYLLUM NASORAKENSIS N. SP.
PLATE 8

FIGURES 1-3. Lithostrotionella niakensis n. sp. Kogruk Formation, north Niak Creek section, 68A-12. 

1,2. 1, Transverse; 2, longitudinal thin section (X 4). Paratype, USNM 161077. 

3. Transverse thin section (X 9). Holotype, USNM 161074.
GEOLOGICAL SURVEY PROFESSIONAL PAPER 743-A PLATE :

^

LITHOSTROTIONELLA NIAKENSIS N. SP.
PLATE 9

FIGURES 1-6. Lithostrotionella niakensis n. sp. Kogruk Formation, north Niak Creek section, 68A-12. 

1,3. 1, Longitudinal; 3, transverse thin section (X 4). Paratype, USNM 161076. 

2,4. 2, Longitudinal; 4, transverse thin section (X 4). Paratype, USNM 161078. 

5,6. Longitudinal thin sections (X 9). Holotype, USNM 161074.
GEOLOGICAL SURVEY PROFESSIONAL PAPER 743-A PLATE 9

r%

LITHOST.ROTIONELLA NIAKENSIS N. SP.

U. S. GOVERNMENT PRINTING OFFICE : 1972 O - 456-832