/•^/<o^?X^'X NAUTILUS
" Ime i^, ^iRift)Jr^j- July i 972

CONTENTS N. 4'

A. Byron Leonard

A New Valvata from the Pleistocene of Southern Illinois 1

William G. Lyons

New Turridae (Gastropoda: Toxoglossa) from South Florida and the Eastern Gulf of Mexico 3

Frasier O. Bingham

Several Aspects of the Reproductive Biology oi Littorina irrorata (Gastropoda) 8

David Nice!

Geologic History of Deposit- feeding Pelecypods 11

Leslie Hubricht

Two New American Pulmonata: Paravitrea seradens and Philomycus sellatus 16

Dorothy E. Beetle

A Note on Land Snails Associated with Kudzu Vine 18

William F. Gale

Seasonal Variability in CalycuUsm in Sphaerium transversum (Say) 20

SHORT PAPERS

Patrick V. Kirch

Subfossil Non-marine Gastropods from Molokai, Hawaiian Islands 23

Jon-Ame Sneli

Odostomia turrita Found on Homanis gammarus 23

James X. Corgan

Pyramidellid Genera of Pilsbry 24

Morris K. Jacobson

Observations on the Siphonal Behavior of Young Surf Clams, Spisula solidissima 25

Book Reviews 10, 19

Dates of Publication of the Nautilus, vol. 85 26

1 'X' *«^ \

Vol. 86 ( 1 ) THE NAUTILUS

A NEW VALVATA FROM THE PLEISTOCENE OF SOUTHERN ILLINO

A. Byron Leonard

Division of Biological Sciences
The University of Kansas
Lawrence, Kansas 66044

ABSTRACT

Valvata salina Leonard ( Prosobranchia: Valvatidae), a new Pleistocene, Wisconsinan
Stage species, is described from the Saline River banks near Equality, Gallatin Co.,
Illinois. It differs from V, tricarinata (Say) in being more planoid, having a low spire and a
proportionately larger umbilicus.

The Saline River and its tributaries comprise a
drainage system of limited extent in southeastern
Illinois; the river arises no farther north than
Hamilton County, and enters the Ohio River in
northeastern Hardin County, an air-line distance of
little more than 60 miles. Especially in Saline and
Gallatin counties, the Saline River and its immediate

tributaries are entrenched in sediments of late
Pleistocene Lake Saline (Willman and Frye, 1970,
Fig, 9, p. 34); artificial deepening, straightening and
cleaning of the channel by heavy earthmoving
equipment has produced many clean exposures of the
ancient lake sediments up to heights of 35 or more
feet at low water stages of the river, although the

FIG. 1, 2, 3: umbilical, apertural and spiral views ofholotype o/ Valvata salina, n. sp. Corresponding views of an
associated example ofV. tricarinata are shown in figures 4, 5, and 6. All figures approximately x 6.

THE NAUTILUS

July 1972

.Vol. 86(1)

total thickness of the lake beds ranges upward to
approximately 1 50 feet. In the course of studying the
molluscan faunas in the fossihferous clays and silts
thus made available, an hitherto unknown member of
Valvata, a genus of branchiate gastropods, was
discovered. Inasmuch as the shells do not intergrade
in their distinguishing characters with those of
Valvata tricarinata (Say) with which they occur, the
shells are described as a new species.
Valvata sahna ru sp.
Figs. 1 , 2, 3

Diagnosis: Shells possessing the general
characteristics of the genus Valvata, and resembling in
many respects Valvata tricarinata (Say) from which it
differs, however, in the following important features:
consistently greater size; more planoid form;
relatively larger umbilical opening; and lack of spiral
sculpture.

Description of holotypes: Shell forming a helicoid
spiral, whorls 3^ in number; spire depressed below
general upper surface; nucleus of VA rounded whorls
bearing granular sculpture; remaining whorls increas-
ing rapidly and uniformly in diameter toward the
aperture, where the last whorl descends slightly;
whorls robust, tricarinate as in typical V. tricarinata,
except that the peripheral carina is reduced to
nothing more than a distinct angulation, and bearing
obvious but not conspicuous diagonally transverse
striations; spiral sculpture lacking on the whorls;
aperture round, entire, and cemented to the
penultimate whorls below the angle of the peripheral
carina; operculum not known; umbilicus relatively
broad, narrowing above, but exposing all the whorls
to the nucleus. Measurements: greater diameter of
shell, 6.9 mm; lesser diamer, 5.5 mm; height of shell,
2.8 mm; diameter of umbilicus, 2.1 mm; diameter of
aperture, 1.6 nun.

Type locality: Equality Northeast Section, in the
NW 1/4, NE 1/4, NW 1/4 sec. 16, T 9 S, R 8 E, Gallatin
County, Illinois. The fossiferous exposure is in the

right bank of the Sahne River, about a mile northeast
of the village of Equality.

Geological horizon: Equality Formation (WiUman
and Frye, 1970, p. 72), Woodfordian substage of the
Wisconsinan Stage of the Pleistocene Series.

Types: The holotype, and paratypes from the type
locahty and from two other localities exposed in
Lake Sahne sediments, are on deposit in the
paleontologjcal collections of the Illinois State
Geological Survey.

Comparisons: At each of the three locaUties from
which Valvata salina was recovered, it occurred with
V. tricarinata, as well as with about 20 other
molluscan species, several kinds of ostracods, seeds of
vascular plants and nucules of Chara and Nitella. The
greater diameter of the shells of V. salina varies
between 6.0 and 7,5 mm, while that of the associated
shells of V. tricarinata ranges from 4.6 mm to 5.0
mm. The planoid form of V. salina is exemplified by
the relation between greater diameter and the height
of the shells; the height comparises only 40 to 45 per
cent of the greater diameter, while in V. tricarinata
from the same deposits the corresponding range is
between 75 and 82 per cent. In shells of V. salina, the
diameter of the umbiMcus comprises from 31 to 34
per cent of the greater diameter of the shells, while in
V. tricarinata the diameter of the umbilicus
represents only 17 to 19 per cent of the greater
diameter. These data confirm the earlier statement
that Valvata salina is not only consistently larger than
examples of V. tricarinata which occur v^th it, but
also that it also differs from the latter in being much
more planoid, and in having a relatively broader
umbilicus.

LITERATURE CITED

Willman, H. B. and J. C. Frye 1970. Pleistocene
stratigraphy of Illinois. Illinois State Geol, Surv.
Bull. 94. 204 pp. 14 figs. 7 tables. 3 pis.
(in pocket).

Vol. 86 (1)

THE NAUTILUS

NEW TURRIDAE (GASTROPODA: TOXOGLOSSA) FROM SOUTH FLORIDA

AND THE EASTERN GULF OF MEXICO
William G. Lyons

Florida Department of Natural Resources
Marine Research Laboratory'
St. Petersburg, Florida 33731

ABSTRACT

Three new species, Cerodrillia gjrardi, Brachycythara barbarae, and Granoturris
presleyi are described primarily from collections taken in the eastern Gulf of Mexico, and
are compared with other related species. Daphnella margaretae is described from south
Florida. Daphnella retifera Dall, D, margaretae, and D. bartschi Dall, a closely related
species from the tropical eastern Pacific, are assigned to the subgenus Paradaphne
Laseron, previously known only from the Indo-Pacific.

Several undescribed turrids were found during
examination of mollusks collected in Project Hour-
glass, a systematic benthic sampling program con-
ducted in the eastern Gulf of Mexico by the Florida
Department of Natural Resources Marine Research
Laboratory (Lyons, 1968; Joyce & Williams, 1969).
New species of Cerodrillia, Brachycythara, and
Granoturris from these collections are described
herein. A previously unknown species of Daphnella
(Paradaphne) from south Florida is also described.

Collections of Recent Turridae of the Academy of
Natural Sciences of Philadelphia, Pennsylvania
(ANSP), the Museum of Comparative Zoology, Cam-
bridge, Massachusetts (MCZ), and the National Mu-
seum of Natural History, Smithsonian Institution,
Washington, D. C. (USNM) were examined during this
investigation. Additional specimens for study were
provided by Mrs. Margaret Kennedy, Delray Beach,
Florida, Dr. James H. McLean, Los Angeles County
Museum of Natural History (LACM), Los Angeles,
California, Mrs. Virginia 0. Maes, ANSP, and Mr. and
Mrs. Daniel Steger, Tampa, Florida.

Type depositories: Holotypes of all species de-
scribed are in the collection of the National Museum
of Natural History. Paratypes, deposited in various
other museums when sufficient material was avail-
able, are Usted in material of each species examined.
DMNH refers to the Delaware Museum of Natural
History.

GENUS Cerodrillia Bartsch & Rehder, 1939

Cerodrillia girardi new species

FIGS. 1, 2

Description: Shell with about 7]6. whorls, small, to
about 12.8 mm total length, solid, turreted, sub-
globose; color uniform waxy amber. Protoconch of 2
smooth, globose whorls passing without interruption
into post-nuclear whorls. Post-nuclear whorls SVi,
each with 7 or 8 strong, retractively curved, some-
what sigmoid ribs, broadest at rounded periphery.
Intercostal spaces broad, smooth except for micro-
scopic incremental Unes and extremely faint spiral
striation. Base short, marked with 7-9 spiral Unes
which increase in strength anteriorly. Aperture sub-
oval, broadest near middle. Columella nearly straight;
inner lip moderately wide, distinct. Outer lip thin,
backed by a thickened varix, irregularly curved, with
a shallow but distinct stromboid notch. Sinus deep,
broad, bordered posteriorly by a thick callus. Canal
very short, broad, shallow.

Material examined: Holotype: USNM 707001.
Length 8.8 mm, width 3.8 mm. Off Egmont Key,
Florida, Hourglass station D, 27°37'N, 83°58'W, 55
m; August 11, 1966. -Single adult paratypes, all from
station D, deposited at ANSP, LACM, MCZ, USNM,
American Museum of Natural History, New York
(AMNH), Delaware Museum of Natural History,
Greenville, Delaware (DMNH) and Florida Depart-

' Contribution no. 205

THE NAUTILUS

July 1972

Vol. 86(1)

ment of Natural Resources Marine Research Lab-
oratory, St. Petersburg, Florida (FSBC I).

Remarks: Cerodrillia girardi sp. nov. is more
globose than C. clappi Bartsch and Rehder, C. perryae
Bartsch and Rehder, or C thea (Dall), though the
nucleus resembles that of C. thea. In general outHne it
is nearest C bealiana Schwengel & McGinty, with
which it is often collected, but the latter is a smaller
species with a much smaller and more pointed
nucleus.

Cerodrillia girardi was never collected in large
numbers during Project Hourglass, but low numbers
were taken frequently at station D. It was collected
only occasionally at stations E, L, and M (55 and 73
m stations). Most specimens other than type material
were juveniles or dead shells in poor condition. There
are specimens in the Steger collection from off the
lower Florida Keys in 49-55 m.

The species is named for Capt. Earl Girard, master

of the R/V Heman Cortez during the Hourglass

cruises.

GEH\}^BrachycytharaV^ooMrvg, 1928

Brachycythara barbarae new species

FIGS. 3, 4

Description: Shell with about 6 whorls, small, to
about 3.5 mm total length, biconic, translucent, with

httle or no spiral sculpture and strong axial ribs.

Protoconch with about 3 whorls, the tip distinctly

defined, not immersed in the next whorl; first two

nuclear whorls smooth, rapidly enlarging, somewhat

compressed axially; third whorl initially with fine,

curved, closely-spaced axial riblets which increase in

strength as they progress downward. Post-nuclear

whorls generally smooth, but faint spiral striae

sometimes present; axial ribs strong, sinuose, sharply

angled at the periphery, giving the whorls an angular

appearance; 8-9 such ribs on the body whorl. A faint

brown spiral band between suture and periphery of

spiral whorls; as many as six such bands below

periphery on body whorl, final band on the base most

broad. Eight or nine unornamented spiral threads on

base. Aperture narrow, about 40 per cent total length

of shell; outer lip thickened, rounded at shoulder;

sinus adjoining suture wide, rounded, very shallow;

parietal callus smooth, fairly broad; columella short,

truncate.

Material examined: Holotype: USNM 707003.

Length 3.4 mm, width 1.6 mm. Off Egmont Key,

Florida, Hourglass station D, 27°37'N, 83°58'W, 55

m; February 28, 1967. -Single adult paratypes, all

from station D, deposited at AMNH, ANSP, DMNH,
FSBC, LACM, MCZ, USNM, and the Steger
collection.

Remarks: Brachycythara biconica (C. B. Adams),
the only other Recent western Atlantic species near
B. barbarae sp. nov., has distinctly beaded spiral cords
on the post-nuclear whorls, giving the surface a
frosted appearance which immediately separates it
from B. barbarae. In addition, B. biconica possesses
more numerous axial ribs (10 -12 on body whorl)
which are rounded, not angled, at the periphery, and
a relatively longer aperture (about 50 per cent total
length of shell). The columella of B. biconica is
straight. The tip of the apex is immersed in the next
whorl, giving the nucleus a blunter appearance than
that oi B. barbarae. The lectotype of 5. biconica alba
(C. B. Adams) (Clench and Turner, 1950; pi. 32, fig.
1) has the frosted sculpture of B. biconica and is
apparently an unusual form of that species.

Bathymetric preferences for B. biconica and B.
barbarae are evident. In Hourglass collections, B.
biconica was common at 18 and 37 m stations but
seldom occurred at greater depths; it occurs in depths
as shallow as 1 m in the Florida Keys. Brachycythara
barbarae was common at 55 and 73 m Hourglass
stations, but was taken only occasionally at the
northern 37 m station (C), and was never taken at the
comparable southern station (K). There is one large
lot in the Steger collection taken southwest of
Sombrero Light, Monroe County, Florida, in 55 m. I
have not seen B. barbarae from shallower than 37 m.

The species is named for Mrs. Barbara Steger in
appreciation of her gracious hospitality during my
examination of the Steger collection.

GENUS Granoturris Fargo, 1953

Granoturris presleyi new species

FIGS. 5, 6

Description: Shell with about 7 whorls, small, to

about 4.7 mm total length, slender, turreted.

Protoconch flesh-colored, prominent, resembhng

Miraclathurella, of about IVi smooth whorls, tip

immersed in following whorl. First H post-nuclear

whorl strongly keeled at periphery as in Cryoturris,

with about 9 axial riblets. Subsequent whorls with

11-12 strong axial ribs, sharply angled at submedian

periphery. A spiral cord connecting peripheral angles,

another somewhat weaker cord midway between

periphery and anterior suture. Pre- and

post-peripheral sculpture of closely-spaced, frosted

Vol. 86(1)

THE NAUTILUS

FIGS. 1, 2 Cerodrillia girardi Lyons, Holotype, 8.8 mm, USNM 707001;

FIGS. 3, 4 Brachycythara barbarae Lyons, Holotype, 3.4 mm, USNM 707003;

FIGS. 5, 6 Granoturris presleyi Lyons, Holotype, 4. 7 mm, USNM 707005;

FIGS. 7, 9 Daphnella (Paradaphne) bartschi Da//, 10.4 mm, LACM collection;

FIG. 8 Daphnella (Paradaphne) margaretae Lyons, Holotype, 10.7mm, USNM 707006.

THE NAUTILUS

July 1972

Vol. 86(1)

spiral threads. Aperture elongate, subovate. Sinus
subsutural, a broad, shallow depression near shoulder.
Outer lip thin, unvariced, angled at shoulder. Anterior
canal short, moderately broad and deep. Post-nuclear
whorls white, with about 5 fine, brown spiral Unes on
post-peripheral portion, a more prominent, darker
brown Une immediately posterior to suture; 3 dark
brown Unes near middle of body whorl, 5 weaker
brown lines toward anterior canal.

Material examined: Holotype: USNM 707005,
Length 4.7 mm, width 1.8 mm. Off Egmont Key,
Florida, Hourglass station B, 27°37'N, 83°07'W, 18
m; November 20, 1967. -Three paratypes, all from
station B: 1 at ANSP, 2 at FSBC.

Remarks: Granoturris presleyi sp. nov. is the first
known Recent species from the western Atlantic; G.
padolina Fargo, from the North St. Petersburg
PUocene, differs from the Recent species by
possession of fewer axial ribs on whorls, and by its
larger size. The shoulders of G. padolina are normally
convex, according to Fargo; on G. presleyi, the
shoulders are always quite flat.

The species is named for Mr. Robert F. Presley,
ship's biologist of the R/V Neman Cortez during the
Hourglass cruises.

GENUS Dop/iwd/fl Hinds, 1844
SUBGENUS Paradaphne LusQron, 1954

Description: Shell small, to about 11.3 mm total
length, moderately thin, fusiform. Nucleus of 4-6
rounded, diagonally cancellate whorls, protractive
threads of cancellation somewhat stronger than
retractives on last whorl. Intersection of nuclear and
post-nuclear sculpture not sharply defined, pro-
tractive nuclear axials overlying for a small distance
post-nuclear spirals. Spire and body whorl with many
spiral lines crossed by axial threads, beaded at
intersections, with or without fine spiral threads in
interspaces. Aperture elongate-ovate, widest near
middle. Sutural sinus moderately deep, reversed
I^shaped, sloping anteriorly. Outer lip simple, curved,
tapered anteriorly, sUghtly thickened within; a very
weak notch at intersection with short, shallow,
moderately wide anterior canal.

Remarks: Powell (1966) dismissed Laseron's
Paradaphne for lack of characters of differentiation
from Daphnella, It is evident, however, that there
exists a circumtropical group of species, differing
markedly from Daphnella in nuclear and post-nuclear
sculpture. Daphnella botanica Hedley, 1918, the type
species o{ Paradaphne, belongs to this group, though

it is one of the species nearest in form to Daphnella

s. s.

Daphnella lymneiformis, the type species of
Daphnella, and closely related species have a smaller,
more slender protoconch of 2!^-3 whorls, with Uttle
variation in the strength of diagonal cancellation of
the last whorl. Intersection of nuclear and post-nu-
clear sculpture is abrupt, without the overlap zone of
Paradaphne. Size, sculpture, and number of whorls of
the protoconch of Paradaphne resemble those of
Metuonella Sorgenfrei, 1958, Cryptodaphne Powell,
1942, and Maoridaphne Powell, 1942, but these three
differ from Paradaphne by variously possessing strong
axial ribs, markedly different apertures and sinuses,
or both. In addition, the outer hp of adult Daphnella
s. s. is flared anteriorly, not tapered and constricted
as in Paradaphne. The aperture and outer lip of
Paradaphne closely resemble those of immature
Daphnella, but the inner thickening of some
specimens indicates that they are mature.

Eudaphne Bartsch, 1931 {non Reuss, 1922) was
proposed to contain Daphnella allemani (Bartsch,
1931). The name was later changed by Bartsch
(1933) to Eudaphnella. Keen (1958) suggested that
perhaps Eudaphne should be used in a subgeneric
sense for D. allemani and D. bartschi Dall, 1919.
However, D. allemani has the wide aperture, flared
outer lip rounded at the sutural sinus, and extremely
short canal of typical Daphnella and is so similar in all
other respects that subgeneric separation seerns
unwarranted, as noted by Powell (1966). Daphnella
bartschi is definitely assignable to Paradaphne, as are
D. retifera Dall, 1889, and a new species herein
described.

Daphnella (Paradaphne) margaretae new species

FIG. 8

Description: Shell with about 8 whorls, small, to
10.7 mm total length. Nucleus of about 5 rounded,
diagonally cancellate whorls, brown except fifth,
which has two spiral rows of large, round, white spots
best seen on wet specimens. Spire and body whorl
sculptured of fairly strong spiral lines crossed by
weaker axial threads, strongly beaded at intersections;
spiral threads within interspaces nearly obsolete.
Aperture slender, elongate; outer Up simple,
thickened within; sinus moderately deep, reversed L-
shaped. Siphonal canal broad, shaUow, brief, but
longer than that of most daphnelUds. Color cream,
with rich brown maculations. Three rows of large,
spot-Uke brown maculations on body whorl at

Vol. 86(1)

THE NAUTILUS

periphery, middle and posterior portion of base.

Material examined: Holotype: USNM 707006.
Length 10.7 mm, width 3.8 mm. South of Dry
Tortugas,Horida, 24°24'N, 82°58'W, 76-85 m; April
27, 1967; R/V Heman Cortez. --Para types: ANSP
324021. Length 5.4 mm, width 2.2 mm. On
Spondylus collected in 37-55 m off Palm Beach
County, Florida, 1970. -FSBC I 7896. Length 4.4
mm, width 2.0 mm. South of Sand Key, Monroe
County, Florida, 35-36 m, August 2, 1971; R/V
Heman Cortez.

Remarks: Radwin (1969: p.233) proposed the
term "cognates" to replace "analogues", as the
meaning of the former more clearly denotes "related
through the same origin" in the immediate biological
sense. Daphnella bartschi from the eastern Pacific and
D. margaretae sp. nov. are obvious cognates and have
probably evolved since emergence of the Central
American isthmus. D. margaretae differs from D.
bartschi (Figs. 7, 9) by possessing stronger spiral lines
crossed by weaker axial threads on the spire and body
whorl. The overall appearance of D. bartschi is of
even cancellation, whereas on D. margaretae spiral
sculpture is the dominant feature. Many fine spiral
threads in interspaces between post-nuclear spiral and
axial sculpture are clearly defined in D. bartschi, but
are nearly obsolete in D. margaretae. Overall, the shell
of D. margaretae is more slender than that of D.
bartschi The double row of large white spots on the
last nuclear whorl and maculations of spire and body
whorl are identical on both.

Daphnella retifera Dall, 1889, has one more
nuclear whorl and a more globose, thirmer shell than
either of the preceding species. Nuclear size, sculpture
of nuclear and post-nuclear whorls, and shape of the
aperture and outer lip indicate the relationship of this
species to the previous two. Interspaces between axial
and spiral sculpture are smooth. Color of the nucleus
is brown; post-nuclear whorls are white, with
scattered yellow maculations.

Daphnella (Paradaphne) margaretae is named for
Mrs. Margaret Kennedy, Delray Beach, Florida, who
provided one of the paratypes and whose articles on
western Atlantic Turridae in Seafari, the bulletin of
the Palm Beach County Shell Club, have stimulated
much interest in this group.

ACKNOWLEDGEMENTS

I thank Dr. James H. McLean and Mrs. Virginia
Maes for critically reading the manuscript and
providing additional information. They, Mrs. Mar-
garet Kennedy and Mr. and Mrs. Daniel Steger kindly
loaned specimens. The many persons who gave
assistance during inspection of collections at the
before-mentioned museums are gratefully acknow-
ledged. Special thanks are extended to Mrs. Sally
Kaicher who produced the photographs.

REFERENCES CITED

Bartsch, P. 1931. Descriptions of new marine

mollusks from Panama, with a figure of the

genotype of Engina, Proc. U. S. Nat. Mus., 79

(2881): 1-10, 1 pi.
Bartsch, P. 1933. Eudaphnella, a new generic name.

Nautilus, 47(2): 76-77.
Clench, W. J. and R. D. Turner. 1950. The western

Atlantic marine mollusks described by C. B.

Adams. Occ. Papers on MoUusks, 1(15): 233-403.
Dall, W. H. 1919. Descriptions of new species of

mollusks of the family Turritidae from the west

coast of America and adjacent regions. Proc. U. S.

Nat. Mus., 56(2288): 1-86, 24 pis.
Fargo, W. G. 1953. The Pliocene Turridae of Saint

Petersburg, Florida. In: Olsson, A, A. and A.

Harbison, 1953. Pliocene Mollusca of southern

Florida. Acad. Nat. Sci. Phila., Monograph 8, Pt.

2: 363-409, pis. 16-24.
Keen, A. M. 1958. Sea shells of tropical West

America; marine mollusks from Lower California

to Colombia, i-xi + 624 pp. Stanford Univ. Press,

Stanford, Calif.
Laseron, C. F. 1954. The New South Wales Turridae.

Roy. Zool. Soc. N. S. W. Handb., pp. 1-56.
Lyons, W. G. 1968. Mollusks of Project Hourglass.

Am. Malacol. Union Ann. Rpts. for 1968: 34-35.
Powell, A. W. B. 1966. The molluscan families

Speightiidae and Turridae. Bull. Auckland Inst.

and Mus., No. 5: 184 pp., 34 pis.
Radwin, G. E. 1969. A recent molluscan fauna from

the Caribbean coast of southeastern Panama.

Trans. San Diego Soc. Nat. Hist., 15(14): 229-236.

8

THE NAUTILUS

July 1972

Vol. 86(1)

SEVERAL ASPECTS OF THE REPRODUCTIVE BIOLOGY OF

LITTORINA IRRORATA (GASTROPODA)

Frasier O. Bingham

University of Miami
Rosenstiel School of Marine and Atmospheric Science ^
1 0 Rickenbacker Causeway
Miami, Florida 33149

ABSTRACT

The salt marsh periwinkle, Littorina irrorata, of eastern United States is dioecious. The
penis has a gray-brown, wrinkled basal region and a smooth, slender, white distal region
with a sperm groove located along the dorsal edge. Copulation, lasting 15 minutes or
longer, occurs in the warmer months and while the snails are out of water on marsh grass.
Females shed between 43,000 and 85,000 clear, planktonic, disc-shaped capsules, each of
which contains one gray egg. Spawning takes place at the air-water interface or just below
the surface of the water at a rate of four or five capsules per second for two to four
hours.

INTRODUCTION

The salt marsh periwinkle, Littorina irrorata (Say)
is common along the northern coast of the Gulf of
Mexico and the eastern coast of the United States
from central Florida to New York.

The observations reported here were made during a
detailed study of the behavior of the species in a salt
marsh near Panama City, Florida (30°14'N, 85°
4rW), during the period January through October,
1969 (Bingham, in press).

THE PENIS

The male copulatory organ was noted to develop
when male specimens reached a shell length of
approximately six mm. After this size is reached, the
separate sexes are easily distinguished by gently
lifting the outer shell lip of specimens that are
extended and firmly adhering to a substrate, and
noting the presence or absence of a penis slightly
below and posterior to the right tentacle (Fig. 1).

The penis has been seen to become larger and more
pigmented during the breeding season in some species
of Littorina (e.g. L. littorea by Tattersall, 1920; L.
augulifera by Linderking, 1954) and to show no such
seasonal variation in others (e.g. L. picta and L.
pintado by Struhsaker, 1966). No change in size or
color was noted in the penis of L. irrorata during the
period of this study which included the breeding
season.

* Contribution no. 1515.

The penis of L. irrorata can be divided externally
into two regions. The basal region (Fig. 2) is
gray-brown and has a wrinkled surface. The distal
region is white and has a fairly smooth surface. During
repose this region is slightly smaller in diameter and
approximately the same length as the basal region.
Located near the base of the basal region, so as to be
hidden from view when the organ is in its reposed
position (Fig. 1), is a light colored, slightly raised
area. Similar structures in L. littorea were found to be
glands and believed by Fretter and Graham (1962) to
secrete mucus used for holding the penis in position
during copulation. A sperm groove is located along
the dorsal edge of the entire length of the organ.

During copulation, the basal, region of the penis
becomes highly engorged with blood (Fig. 3) while
the distal region lengthens and decreases in diameter
so as to become thread-hke (Fig. 3).

COPULATION

Weekly observations of the snails in the salt marsh
were begun on January 4, 1 969. Copulation was first
noted during the afternoon of May 5 when about
25% of the animals were copulating, either at the
air-water interface or on grass shoots and leaves above
the water. The female of a copulating pair is always
firmly attached to the marsh grass with the foot
extended and, in most instances, in a spire-down
position. The male secures a firm hold on the female's

Vol. 86(1)

THE NAUTILUS

shell with its extended foot and comes to rest with
the right side of its shell hp slightly overlapping the
same portion of the female's shell. After the male is
in this position, the penis is directed into the mantle
cavity of the female and quickly inflates (Figure 4).
The length of time spent in copulation in 17 pairs
ranged from 24 to 36 minutes. During copulation and
for 15 minutes or longer thereafter, no locomotory
movements were seen in either sex.

High temperatures may be the stimulus for
copulation as suggested by the fact that during the
months of May, June and July, copulation was
observed on each field trip made in hot, clear weather
and no copulation was seen during two field trips
taken in cool, overcast weather conditions. In
studying this possibility, 150 specimens were
collected in the marsh on July 12 and brought to the
laboratory. Fifty specimens were placed in each of
three shallow pans which contained small amounts of
seawater and were covered with wire screens to
prevent the snails' escape. One pan was put outside in
the sunlight, one pan was left on a table in the
laboratory at 21°C, and one was placed in an oven set
at 40° C. No copulation occurred in the pan kept in
the laboratory. Copulation began in the sunlighted
pan and in the oven heated pan when a temperature
of 35°C was reached in each, and continued in both
pans for about two hours even though the pan in the
oven was taken out and allowed to cool to room
temperature (21*'C).

Tattersall (1920) noted that L. littorea kept in an
aquarium began to copulate soon after a water
change. He believed copulation to be induced either
by higher levels of dissolved oxygen or a decrease in
temperature. Alterations in temperature could also
have been involved when Lenderking(1954) observed
large numbers of L. augulifera copulating soon after
heavy rains.

Copulation in L. inorata was not seen in the marsh
after September 28, and specimens collected there-
after could not be induced to mate regardless of the
temperature at which they were maintained.

SPAWNING

Females which mated in the laboratory during the
afternoon of May 6 began spawning the next after-
noon at 1:10 PM, just 16 minutes after high tide
occurred in the area from which they were collected.
Specimens taken during the next several months
began spawning without regard to dayUght or dark-
ness at approximately the same time as the next high
tide after copulation.

A few females spawned while completely sub-
merged, but most were positioned at the air-water
interface (Fig. 5). Egg cases were continuously
expelled at a rate of four or five per second for a
period of two to four hours, and formed cloudy paths
to the bottom of the animals' containers. Two
females were isolated after copulation and their eggs
counted using a tally counter, grid slide and a known
volume of seawater in which the eggs had been

PENIS

FIG. 1. Repose position of the penis in L. irrorata.

FIG. 2. View of side of penis lying next to body. Penis in repose state. A - basal region; B - attachment gland; C ■

sperm groove; D - distal region.

FIG. 3. Penis engorged and the distal region in an extended state. A - basal region; B - attachment gland; C ■

sperm groove; D - distal regiori

10

THE NAUTILUS

July 1972

Vol. 86(1)

suspended by agitation. One snail laid approximately
43 thousand, and the other 85 thousand eggs.

THE EGG AND EGG CAPSULE
• L. irrorata lays clear, planktonic, disc-shaped egg
capsules which contain one gray egg each (Fig. 6).
The capsules measure from 250 to 280 n in diameter,
and are somewhat negatively buoyant in still seawater
of 26%o salinity.

LITERATURE CITED
Bingham, F. 0. In Press. The influence of en-
vironmental stimuli on the direction of movement

.i:t\>.<:-*.

•' :■'■•'**'•■

of the supraUttoral gastropod Littorina irrorata.

Bull. Mar. Sci.
Fretter, V. and A. Graham. 1962. British Prosobranch

Molluscs. Ray Society, London. 755 p.
Lenderking, R. E. 1954. Some recent observations on

the biology of Littorina angulifera Lam. of Bis-

cayne and Virginia Keys, Florida. Bull. Mar. Sci.

Gulf and Caribbean 3: 272-296.
Struhsaker, J. W. 1966. Breeding, spawning, spawning

periodicity and early development in the Hawaiian

Littorina: L. pintado (Wood), L. picta (Philippi)

and L. scabra (Linne). Proc. malac. Soc. Lond. 37:

137-166.
Tattersall, W. M. 1920. Notes on the breeding habits

and Ufe history of the periwinkle. Sci. Invest. Fish.

Br. Ire. 1: 1-11.

-250A

FIG. 4. Simplified drawing of copulating pair of L.
irrorata as seen through a glass substrate. A -male; B -
female.

FIG. 5. Simplified drawing of female L. irrorata
spawning

FIG. 6. Egg and egg capsule of L. irrorata. A - egg; B
egg capsule.

BOOK REVIEW

SEA SHELLS COMMON TO NORTH CAROLINA.

By Hugli J. Porter and Jim Tyler. 36 pp., 131 figs.,
colored cover on paperback. 1971. Free copy
obtained by writing: Division of Commercial and
Sports Fisheries, Dept. Natural Resources, More-
head City, N. C. 28557.

This is a well-illustrated and accurate guide to 1 29
marine mollusks of the coast of North CaroUna. It is a

paperback booklet designed for seashore visitors to
this part of the world. It contains both popular and
scientific names, brief descriptions, relative
occurrences, and habitats. The species are con-
veniently arranged in a series of simple keys and
illustrated by either drawings or clear photographs.
An index and glossary are included.
R. Tucker Abbott
Delaware Museum of Natural History

Vol. 86 (1)

THE NAUTILUS

11

GEOLOGIC HISTORY OF DEPOSIT-FEEDING PELECYPODS

David Nicol

Box 14376, University Station,
Gainesville, Florida 32601

ABSTRACT

All Paleozoic faunas average 10 per cent deposit-feeding pelecypods, with a range from
0 to 15 per cent. The Mesozoic pelecypod faunas average only 8 per cent deposit feeders,
with a range from 0 to 18 per cent. Of the Cenozoic faunas exluding the Recent, the
average percentage of deposit feeders is 16 per cent, with a range from 11 to 38 per cent.
There was a rapid increase in diversity of deposit-feeding pelecypods beginning in the
Paleocene. In the shallow-water Recent faunas the average percentage of deposit-feeding
pelecypods is 19 per cent, with a range of from 7 to 29 per cent, the Arctic having the
highest percentage. Deposit-feeding pelecypods are now at least as diverse as they have
ever been in the past. There is a higher percentage of deposit-feeding pelecypods (27 per
cent) in silty formations, than in sandy areas (12 per cent) or marl (10 per cent). There
appear to be at least 5 variables in the occurrence of deposit-feeding pelecypods - the
type of bottom sediment; geographic distribution; water temperature; bathymetric depth
and the evolutionary stage of development. The protobranchs originated in the
Ordovician, whereas the deposit-feeding tellinaceans are a relatively modem group,
appearing in the Early Cretaceous.

Protobranchs, which are deposit feeders, are a
minor element in most marine pelecypod faunas from
Ordovician to Recent. In a sample of 13 Paleozoic
faunas, protobranchs average 10 per cent of all
pelecypod species. This figure is quite consistent in
most of the Paleozoic faunas, although in 7 Permian
faunas the average is 11 per cent. The highest
percentage of all Paleozoic faunas, 1 5 per cent, is also
found in 2 Permian faunas.

The Triassic, Jurassic, and Early Cretaceous
(Albian and older) have lower percentages of proto-
branchs than is the average in the Paleozoic. The
average percentage for the Triassic and also the
Jurassic is 5 per cent and that for the Early
Cretaceous is only 4 per cent. The Late Cretaceous
faunas have an average of 7 per cent protobranchs,
but this average is high because of the Kemp Clay of
Texas, in which protobranchs comprise 16 per cent of
the pelecypod species (Stephenson, 1941). It is
interesting to note that the Kemp Clay is the
youngest Cretaceous formation in Texas and is Late
Maastrichtian in age. It is possible that the sudden
increase in protobranch species in a Late Cretaceous

fauna is an indication of colder seas at the end of the
Mesozoic.

The trend toward higher percentages of proto-
branchs continues in the Paleocene (3 faunas that
average 12 per cent protobranchs) and through the
Eocene (4 faunas average 13 per cent protobranchs).
Beginning with the Oligocene the percentage of
protobranchs decHnes considerably. Two OHgocene
pelecypod faunas average only 7 per cent proto-
branchs. Seven Miocene faunas average 9 per cent
protobranch species, and this includes a remarkable
fauna, the Miocene of Astoria, Oregon (Moore,
1963), in which 25 per cent of the pelecypod species
are protobranchs. The 2 Pliocene faunas average only
4 per cent protobranchs, and the 2 Pleistocene faunas
7 per cent protobranchs. The marked reduction of
protobranch species in shallow-water marine faunas
beginning in the Oligocene may be due to more
deposit- fee ding tellinaceans supplanting protobranchs
in this envirormient.

In the Recent marine faunas, protobranchs range
from 1 2 to 23 per cent only in the polar and most of
the cold-temperate faunas where the average tem-

12

THE NAUTILUS

July 1972

Vol. 86(1)

perature of the water is 10°C or less. The highest
percentage, 23 per cent protobranchs, is found in the
Arctic, but only 13 per cent of all Antarctic
pelecypod species are protobranchs. In the tropical
and warm-temperate marine faunas, the protobranchs
range from 1 to 7 per cent of each pelecypod fauna.

There are 3 fossil pelecypod faunas that are devoid
of protobranchs. The Permian Whitehorse fauna
(NeweU, 1940) has only 14 species of pelecypods,
none of which are protobranchs. The Early Triassic
fauna described by Ciriacks (1963) contains 23
species, but none are protobranchs. A Pleistocene
fauna from southwestern Japan described by
Hayasaka (1961) contains 87 species; none are
protobranchs, but there are 10 species of
deposit-feeding teUinaceans. The relatively coarse
sediment comprising the Whitehorse Sandstone was
not conducive to deposit feeding, and 14 pelecypod
species are suspension feeders. No explanation can be
given for the absence of protobranchs in the Early
Triassic fauna described by Ciriacks. The lack of
protobranchs in the Pleistocene fauna from south-
western Japan may be attributed to the fact that it
was a shallow warm-water environment suitable for
deposit-feeding tellinaceans but unsuitable for proto-
branchs.

No Jurassic or older pelecypod faunas analyzed
had undoubted deposit-feeding tellinaceans, (See
Pohlo, 1968, for deposit-feeding and
non-deposit-feeding teUinaceans) although this super-
family has been reported in rocks as old as Late
Triassic or Early Jurassic. Throughout the Cretaceous,
deposit-feeding teUinaceans (the TeUinidae) comprise
no more than 6 per cent of the total pelecypod
species in any of the 1 1 faunas analyzed, but none of
these faunas was devoid of the TeUinidae. Only the
Wangaloan (Paleocene) beds of New Zealand lack
deposit-feeding teUinaceans (Finlay and Marwick,
1937). The remainder of the Paleocene, the Eocene,
the Oligocene, and a few of the early Miocene faunas
have deposit-feeding teUinacean species comprising 5
to 9 per cent of the pelecypod species. Most Middle
Miocene faunas and aU Late Miocene faunas have 10
per cent or more deposit- feeding teUinaceans. This is
true also of the 2 PUocene and 2 Pleistocene faunas
analyzed. The oldest Miocene fauna that has at least
10 per cent deposit- feeding teUinaceans is the Chipola
Formation of Florida, and it is considered to be Late
Early Miocene in age. By Middle Miocene time the

diversity of deposit- feeding teUinaceans had reached
approximately its present level.

In Recent faunas there is a higher percentage of
deposit-feeding teUinaceans in warm water than in
cold water. In water temperature of 20°C or higher,
deposit-feeding teUinaceans range from 9 to 19 per
cent of the total pelecypod fauna. In colder waters
the deposit- feeding teUinaceans range from 0 to 10
per cent. There is an interesting geographic trend
superimposed on that of water temperature. In the
southern hemisphere the number of species of de-
posit-feeding teUinaceans is considerably lower than
in the northern hemisphere. The South AustraUan
and New Zealand faunas have only 4 per cent
deposit-feeding teUinacean species, the Tasmanian
and MageUanic faunas have only 3 per cent, and the
Antartic pelecypod fauna has none. On the other
hand, the fauna at Monterey Bay, California, has 10
per cent deposit- feeding teUinacean species, that of
Canada 9 per cent, and that of the Arctic 6 per cent.

Beginning with the Cretaceous, one can compare
the diversity of the protobranchs to the de-
posit-feeding teUinaceans in the various fossU
pelecypod faunas. The Early Cretaceous pelecypod
faunas have few species of deposit-feeding teUinids,
but there is an increase in number of species in
Cenomanian faunas, which are commonly considered
the oldest Late Cretaceous. The oldest pelecypod
fauna where teUinid species outnumber protobranch
species is in the Aptian, Early Cretaceous of Lebanon
(Yokes, 1940). However, there are only 5 de-
posit-feeding species in this fauna, comprising 9 per
cent of the total pelecypod species. Of the 9 Late
Cretaceous pelecypod faunas examined, 3 have more
teUinid species than protobranch species. The 3
Paleocene and 4 Eocene faunas have a greater number
of protobranch species than teUinacean de-
posit-feeding species, despite the fact that the
semeUds, which are also deposit- feeding telUnaceans,
first appeared in the Eocene. Of the 2 Oligocene
faunas, one has a greater number of deposit-feeding
teUinacean species than protobranch species. How-
ever, beginning with the Miocene the teUinacean
deposit-feeding species more commonly outnumber
the protobranch species. Of 7 Miocene pelecypod
faunas analyzed, only 2 have more species of proto-
branchs than of deposit-feeding teUinaceans. These 2
are the Shoal River Miocene of Florida (Gardner,
1926-1928) and the Miocene of Astoria, Oregon

Vol. 86(1)

THE NAUTILUS

13

(Moore, 1963). In all 4 Pliocene and Pleistocene
faunas, the deposit-feeding tellinacean species out-
number the protobranch species. Thus, from Miocene
onward, most of the fossU pelecypod faunas are
similar to Recent warm-water faunas (average tem-
perature 20°C or higher, Nicol, 1969) in that the
deposit-feeding tellinaceans outnumber the proto-
branch species. It is obvious from these data that the
ratio of percentages of teUinacean deposit-feeding
species to protobranch species in pelecypod faunas
older than Miocene is an unreUable indicator of water
temperature, and in even some of the Early and
Middle Miocene pelecypod faunas, water temperature
may not be too accurately indicated by the proto-
branch-tellinacean species ratio.

In summation on the diversity of deposit-feeding
pelecypods through time, all Paleozoic faunas average
10 per cent deposit feeders, with a range from 0 to 15
per cent. The Mesozoic pelecypod faunas average
only 8 per cent deposit feeders, with a range from 0
to 1 8 per cent. Of the Cenozoic faunas excluding the
Recent, the average percentage of deposit feeders is
16 per cent, with a range from 11 to 38 per cent. The
fauna with 38 per cent deposit-feeding pelecypods is
from the Middle Miocene of Astoria, Oregon. It is
interesting to note the rapid increase in diversity of
deposit-feeding pelecypods beginning in the
Paleocene. In the shallow-water Recent faunas the
average percentage of deposit-feeding pelecypods is
1 9 per cent, with a range of from 7 to 29 per cent,
the Arctic having the highest percentage but closely
followed by Canada. Deposit-feeding pelecypods are
now at least as diverse as they have ever been in the
past.

Purdy (1964) pointed out that there is a higher
percentage of deposit- feeding marine animals in silt
and clay substrates than in the coarse sediments such
as sands, where deposit feeders are few or absent. In
the fossil faunas analyzed, where there are reliable
data on the Uthology of the beds, the following
results were obtained. In 6 sandy formations the
average percentage of deposit-feeding pelecypods is
12 per cent. In 5 marl and Umestone formations the
average percentage of deposit- feeding pelecypods is
only 10 per cent. This is surprising in that the
percentage is lower than in the sandy formations. In 3
silty formations the average percentage of de-
posit-feeding pelecypods is 27 per cent

There appear to be at least 5 variables in the
distribution of, or diversity of, deposit-feeding

pelecypods. The type of bottom sediment is defin-
itely a factor. There is a greater percentage of
deposit- fee ding pelecypods in clays and sUts than in
sands and limestones. Geographic distribution can be
a factor in the diversity of deposit-feeding
pelecypods at a given locality. At present there are
considerably fewer deposit-feeding tellinaceans in the
southern hemisphere than in the northern hem-
isphere, and this mainly explains why the southern
hemisphere pelecypod faunas have a lower percentage
of deposit feeders. The paucity of deposit-feeding
tellinaceans in the Recent faunas of the southern
hemisphere may explain why there are none of these
pelecypods in the Wangaloan (Paleocene) of New
Zealand. In other words, the deposit-feeding
tellinaceans originated in the northern hemisphere
and are still not so diverse in the southern hem-
isphere. Water temperature is a factor in de-
posit-feeding pelecypod distribution today, with
protobranchs dominating the colder waters. Water
temperature is also closely linked with water depth.
In deeper water there is generally a higher percentage
of deposit feeders, and at great depths (2000 meters
or more) the protobranchs comprise at least 35 per
cent of the total pelecypod species. The stage of
diversity or evolution of the protobranchs and de-
posit-feeding tellinaceans is another important var-
iable. The protobranchs are an ancient stock, going all
the way back to the Ordovician, whereas the de-
posit-feeding teUinaceans are a relatively modern
group, appearing in the Early Cretaceous but not
attaining their present great diversity until about the

Middle Miocene.

In order to conserve space, I have not cited in the

main body of this paper each reference that I
analyzed, but all references are included in the
bibhography. Fourteen Recent and 50 fossil
pelecypod faunas are analyzed. Of the fossil faunas,
19 are Cenozoic, 18 are Mesozoic, and 13 are
Paleozoic in age. I have excluded the Recent deep-sea
pelecypod fauna because all of the fossil faunas
analyzed are from shallow water. Deep-water sed-
iments of the past are rarely available for study, and
modern deep-water faunas are quite different from
fossil shallow-water faunas.

LITERATURE CITED
Arkell, W. J. 1929-1937. A monograph of British

CoraUian Lamellibranchiata. Palaeontographical

Soc. pts. 1-10: 1-392.
Bird, S. 0. 1968. A pelecypod fauna from the

14

THE NAUTILUS

July 1972

Vol. 86 (1)

Gaptank Formation (Pennsylvanian) West Texas.

Bull. Am. Paleo. 54 (240): 11 1-185.
CarceUes, A. R., and S. I. Williamson 1951. Catalogo

de los moluscos marinos de la Provincia

Magallanica. Argentine Mus. Ciencias Nat., Bol.,

Ciencias Zool. 2 (5): 225 -283.
Chavan, A. 1952. Les pelecypodes des sables

Astartiens de Cordebugle (Calvados). Mem. Suisses

de Paleo. 69: 1-132.
Chronic, H. 1952. Molluscan fauna from the Permian

Kaibab Formation, Walnut Canyon, Arizona. Bull.

Geol. Soc. Am. 63 (2): 95-166.
Ciriacks, K. W. 1963. Permian and Eotriassic bivalves

of the middle Rockies. Bull. Am. Mus. Nat. Hist.

125(1): 1-100.
Clark, W. B. and G. C. Martin 1901. The Eocene

deposits of Maryland. Maryland Geol. Survey

Eocene Vol. 1, 331 p.
Cotton, B. C. and F. K. Godfrey 1938. The molluscs

of South Australia, part 1, The Pelecypoda.

Government Printer, Adelaide, South Australia.

314 p.
Dall, W. a, P. Bartsch and H. A. Rehder 1938. A

manual of the Recent and fossil marine pelecypod

mollusks of the Hawaiian Islands. Bernice P.

Bishop Mus. Bull. 153: 1-233.
Dickens, J. M. 1963. Permian pelecypods and gas-
tropods from Western Australia. Bur. Mineral Res.,

Geol. and Geophysics, Australia, Bull. 63: 1-202.
DuBar, J. R. 1958. Stratigraphy and Paleontology of

the Late Neogene strata of the Caloosahatchee

River area of southern Florida. Florida Geol.

Survey Bull. 40: 1-267.
Finlay, H. J. and J. Marwick 1937. The Wangaloan

and associated molluscan faunas of

Kaitangata-Green Island Subdivision. New Zealand

Geol. Survey Paleo. Bull. 15: 1-140.
Gardner, J. A. 1916. Upper Cretaceous, Vol. 1 text,

Vol. 2 text and plates. Maryland Geol. Survey.
1-1022.
Gardner, J. A. 1926-1928. The molluscan fauna of
the Alum Bluff Group of Florida. U. S. Geol.
Survey Prof. Papers 142A-E: 1-249.
Gardner, J. A. 1935. The Midway Group of Texas.

Univ. Texas Bull. 3301: 1-403.
Gilbert, H. and J. de H. de Braucourt 1954.
1 ! '!30c^ne mferieur Beige. Vol. Jubilaire Victor
Siraelan, Inst. Pvoy. Sci. Nat. Belgique. 1:

;'■ j-?48.

Gorges, J. 1952. Die Lamellibranchiaten und Gas-

tropoden des Oberoligozanen Meeressandes von

Kassel. Abh. hess. L.-Amt Bodenforsch.,

Wiesbaden, 4: 1-134.
Harris, G. D. and K. V. W. Palmer 1946. The MoUusca

of the Jackson Eocene of the Mississippi Em-

bayment (Sabine River to the Alabama River).

Bull. Am. Paleo. 30 (1 1 7): 1-563.
Hayami, I. 1965-1966. Lower Cretaceous marine

pelecypods of Japan, parts 1-3, Mem. Faculty Sci.,

Kyushu Univ., Ser. D, Geol., 15 (2): 221-349, 17

(2): 73-150, 17(3): 151-249.
Hayasaka, S. 1961. The geology and paleontology of

the Atsumi Peninsula, Aichi Prefecture, Japan. Sci.

Reports Tohoku Univ., Sendai, 2nd Ser. (Geol.).

33(1): 1-103.
Hind, W. 1896-1900. A monograph of the British

Carboniferous Lameilibranchiata. parts 1-5,

Palaeontographical Soc. London. 1-476.
Isberg, 0. 1934. Studien liber Lamellibranchiaten des

Leptaenakalkes in Dalarna. Hakan Ohlssons

Buchdruckerei, Lund, Sweden. 1-492.
Keen, A. M. 1958. Sea shells of tropical west

America. Stanford Univ. Press, California. 1-626.
La Rocque, A. 1950. Pre-Traverse Devonian

pelecypods of Micliigan. Contrib. Mus. Paleo.,

Univ. Michigan. 7 (10): 271-356.
La Rocque, A. 1953. Catalogue of the Recent

Mollusca of Canada. Nat. Mus. Canada Bull. 129:

1-406.
Logan, A. 1967. The Permian Bivalvia of northern

England. Palaeontographical Soc, London. 121

(518): 1-72.
Mansfield, W. C. 1932. Miocene pelecypods of the

Choctawhatchee Formation of Florida. Florida

Geol. Survey Bull. 8: 1-240.
Manfield, W. C. 1937. Mollusks of the Tampa and

Suwannee Limestones of Florida. Florida Geol.

Survey BuU. 15: 1-344.
Marwick, J. 1953. Divisions and faunas of the

Hokonui System (Triassic and Jurassic). New

Zealand Geol. Survey Paleo. Bull. 21: 1-141.
May, W. L. and J. H. Macpherson 1958. An illustrated

index of Tasmanian shells. Government Printer,

Tasmania. 1-72.
McAlester, A. L. 1962. Upper Devonian pelecypods

of the New York Chemung Stage. Peabody Mus.

Nat. Hist., Yale Univ., Bull. 16: 1-88.
Mongin, D. 1967. Les niollusques du Bathonien

Vol. 86(1)

THE NAUTILUS

15

Saumatre du moyen Atlas. Notes et Mem. Serv.
geol. Maroc. 200: 37-94.

Moore, E. J. 1963. Miocene marine moUusks from the
Astoria Formation in Oregon. U. S. Geol. Survey
Prof. Paper 419: 1-109.

Nakazawa, K. and N. D. Newell 1968. Permian
bivalves of Japan. Mem. Fac. Sci., Kyoto Univ.,
Ser. Geol. and Mineralogy. 35 (1): 1-108.

Newell, N. D. 1940. Invertebrate fauna of the Late
Permian Whitehorse Sandstone. Bull. Geol. Soc.
Am. 51: 261-336.

Nickles, M. 1950. Mollusques testaces marine de la
cote occidentale d'Afrique. Manuels
Quest- Africains, Paris II. 1-269.

Nicol, D. 1967. Some characteristics of cold-water
marine pelecypods. Jour. Paleo. 41 (6):
1330-1340.

Nicol, D. 1969. Deposit- feeding pelecypods in Recent
marine faunas. Trans.-Gulf Coast Assoc. Geol. Soc.
19: 423-424.

Olsson, A. A. 1961. Mollusks of the tropical eastern
Pacific particularly from the southern half of the
Panamic-Pacific faunal province (Panama to Peru):
Panamic-Pacific Pelecypoda. Paleo. Res. Inst., Ith-
aca, New York. 1-574.

Perry, L. M. and J. S. Schwengel 1955. Marine shells
of the western coast of Florida. Bull. Am. Paleo.
26(95): 1-318.

Pohlo, R. 1969. Confusion concerning deposit feed-
ing in the Tellinacea. Proc. Malacologjcal Soc.
London. 38 (4): 361-364.

PoweU, A. W. B. 1946. The shellfish of New Zealand.
Whitcombe and Tombs, Christchurch, New Zea-
land, 2nd. ed. 1-106.

Purdy, E. G. 1964. Sediments as substrates, in J.
Imbrie and N, D. Newell, Approaches to
paleoecology. John Wiley and Sons, New York.
238-271.

Schmidt, M. 1928. Die Lebewelt unserer Trias.
Ferdinand Rau, Ohringen, Germany. 1-461.

Smith, A. G. and M. Gordon, Jr. 1948. The Marine
mollusks and brachiopods of Monterey Bay, Cal-

ifornia, and vicinity. Proc. Calif. Acad. Sci., 4th.

Ser. 26 (8): 147-245.
Stenzel, H. B., E. K. Krause and J. T. Twining 1957.

Pelecypoda from the type locality of the Stone

City Beds (Middle Eocene) of Texas. Univ. Texas

pub. 5704: 1-237.
Stephenson, L. W. 1923. The Cretaceous formations

of North Carohna. Part 1. Invertebrate fossils of

the Upper Cretaceous formations. North Carolina

Geol. Survey. 5 : 1-604.

Stephenson, L. W. 1941. The larger invertebrate
fossils of the Navarro Group of Texas. Univ. Texas
pub. 4101: 1-641.

Stephenson, L. W. 1953. Larger invertebrate fossils of
the Woodbine Formation (Cenomanian) of Texas.
U. S. Geol. Survey Prof Paper 242: 1-226.

Yokes, H. E. 1939. Molluscan faunas of the
Domengine and Arroyo Hondo Formations of the
California Eocene. Ann. New York Acad. Sci. 38:
1-246.

Yokes, H. E. 1 946. Contributions to the paleontology
of the Lebanon Mountains, RepubUc of Lebanon,
part 3. The pelecypod fauna of the "Olive Lo-
cality" (Aptian) at Abeih. BuU. Am. Mus. Nat.
Hist. 87(3): 143-215.

Yokes, H. E. 1957. Miocene fossils of Maryland.

Maryland Geol. Survey Bull. 20: 1-85.
Wade, B. 1926. The fauna of the Ripley Formation

on Coon Creek, Tennessee. U. S. Geol. Survey

Prof Paper 137: 1-272.
Warmke, G. L. and R. T. Abbott 1961, Caribbean

seashells, Livingston PubUshing Co., Narberth,

Pennsylvania. 1-348.
Wilson, A. E. 1956. Pelecypoda of the Ottawa

Formation of the Ottawa-St. Lawrence lowland.

Geol. Survey Canada BuU. 28: 1-102.
Winters, S. S. 1963. Supai Formation (Permian) of

eastern Arizona. Geol. Soc. Am. Mem. 89: 1-99.
Woodring, W. P. 1925. Miocene mollusks from

Bowden, Jamaica. Pelecypods and scaphopods.

Carnegie Inst. Washington pub. 366: 1-222.

16

THE NAUTILUS

July 1972

Vol. 86(1)

TWO NEW NORTH AMERICAN PULMONATA: PARA VITREA SERADENS

AND PHILOMYCUS SELLATUS
Leslie Hubricht

4026 35th Street
Meridian, Mississippi 39301

ABSTRACT

Paravitrea seradens Hubricht (Zonitidae) from Gauley Bridge, Fayette Co., West
Virginia, and the slug Philomycus sellatus Hubricht from Princeton, Jackson Co.,
Alabama, are described as new species. Additional geographical records are given for
Helicodiscus triodus Hubricht. Anatomical notes are made on Triodopsis occidentalis
(Pilsbry and Ferriss) and Polygyriscus virginianus (P. R. BurchJ.

Triodopsis occidentalis (Pilsbry & Ferriss)
Triodopsis obstricta occidentalis (Pilsbry and Ferriss),
Pilsbry, H. A., 1940, Land Mollusca of North
America (north of Mexico). Aca. Nat. Sci. Phil-
adelphia, Mono. 3, 1 : 829.
Mesodon sargentianus (Johnson & Pilsbry),
Vagvolgyi, J., 1968, BuU. Mus. Comp. Zool. 136:
210.

1 recently collected this species alive near Locust
Grove, Independence Co., Arkansas. The genitaha was
found to be similar to that of T. denotata (Ferussac)
(Pilsbry, fig. 473-6.). The shell appears to be a
connecting Unk between T. obstricta (Say) and T.
fosteri (F. C. Baker). The aperture is somewhat
intermediate between these two species. The
periphery varies from strongly angulate to carinate.
Paravitrea seradens new species
FIGS. la-c.
Description: Shell small, pale amber, subhyaline,
glossy; spire low, dome-shaped, sutures shallow,
sculpture of numerous irregularly spaced radial
grooves; periphery somewhat flattened giving the
shell a quadrate appearance in immature shells,
becoming more rounded at maturity; umbilicus deep
and well-like exhibiting all the whorls, contained over
5 times in the diameter of the shell, base flattened
and excavated around the umbihcus; whoris slowly
expanding, last whorl expanding more rapidly and
deflected downward to the aperture; aperture lu-
nate, obhque; lip thin, simple; internal armature of
one or more pairs of rather large teeth on the outer

and basal walls at all stages of growth, except in an
occasional very old shell.

Height 2.8 mm., diameter 5.5 mm., aperture
height 2.0 mm,, diameter 2.5 mm., umbilicus di-
ameter 1.0 mm,, 6.9 whorls. Holotype.

Distribution: West K/rgzw/a; Kanawha Co.: wooded
hillside, Hernshaw. Fayette Co.: below Cane Branch
Falls, 1.5 miles east of Gauley Bridge, holotype
173020 and paratypes 173021 Field Museum of
Natural History, other paratypes A8774 collection of
the author. Wyoming Co.: mountainside, 2.8 miles
northeast of Wolf Pen. Logan Co.: ravine, 4.8 miles
southwest of Holden. Mingo Co.: Gyandot River
bluff, opposite Justice; mountainside, 0.7 mile north
of Cinderella. McDowell Co.: ravine, 4 miles north-
east of Welch.

Remarks - Paravitrea seradens is most closely
related to P. capsella (Gould) differing in having at
least one pair of teeth at all stages of growth; in
having a more expanded aperture; in having the base
more impressed around the umbilicus; and in having a
larger umbilicus in immature shells, the umbilicus
being more well-like. The type locality for this species
is also the type locaHty for Helicodiscus triodus
Hubricht and Carychium clappi Hubricht.

Polygyriscus virginianus (P. R. Burch)
Polygyra virginianus P. R. Burch, 1 947, The Nautilus

61:40.
Polygyriscus virginianus (P. R. Burch), Burch J. B.,

1962, How to Know the Eastern Land Snails. Wm.

C, Brown Co., Dubuque, Iowa. p. 148.

Vol. 86(1)

THE NAUTILUS

17

On a recent visit to the type locality I succeeded
in collecting a series of living specimens of this
species by "mining" at the right spot. Immature
shells have epidermal fringes on the spiral ridges, and
look very much like immature Helicodiscus
fimbriatus Wetherby, but are without teeth. After
maturity these fringes wear off and they are com-
pletely gone in old shells. In adults there is a
transverse tooth on the base a short distance within
the aperture. This was not mentioned in the original
description. P. virginianus seems closely related to
Helicodiscus but whether it should be placed in that
genus is left open pending anatomical studies.
Helicodiscus triodus Hubricht

This species can be added to the growing list of
cave snails, as it has been found living in the two
caves listed below.

West Virginia: Monroe Co.: McClungs Cave,
Zenith. Greenbrier Co.: McClungs Cave, 1.5 miles
northeast of Maxwelton. These two caves are not
connected, although they have the same name. They
are about thirty miles apart.

Philomycus sellatus new species
FIGS. Id-e

Description: The mantle pattern is black on a
white or cream background in very young slugs; as
they become older the pattern becomes lighter, dark
gray in half-grown slugs and brownish gray in adults
and the background becomes darker so that the
pattern is somewhat obscured. The forward end of
the mantle is irregularly mottled; behind this is an
area in which the dark pigment is greatly reduced.
About one-third of the way back is a transverse dark
band with irregular margins. On the latter half of the
mantle there is a broad dorsal band which is bordered
by a series of elongated black spots. On each side
there is a narrow longitudinal band m\h irregularly
scattered mottling above and below. This mottUng
may become so thick as to obscure the lateral bands
and merge them with the dorsal band. The tentacles
are dark gray, and the foot is white. The maximum
length of adults when extended in crawling is about
100 mm.

Distribution: Alabama: Jackson Co.: wooded hill-
side, 1.7 miles northeast of Princeton, holotype
157322 F. M. N. H., paratypes 30066 collection of
the author; base of Putnam Mtn., 4 miles northwest
of Princeton; Woodville (H. E. Sargent); Russell Cave

FIG. lA-C. Paravitrea seradens Hubricht, holotype.
FIG. ID-E. Philomycus sellatus Hubricht, holotype.

National Monument. Madison Co.: wooded hillside,
1.3 miles northeast of New Hope: base of Sharp
Mtn., near Sneeds Spring, Sharps Cove, northeast of
Maysville. Tennessee: Franklin Co.: hilltop, 2.5 miles
south-southeast of Huntland. Marion Co.: Raven Den
Point Sink, 1.8 miles west of Martin Spring.

Remarks: Philomycus sellatus is most closely re-
lated to P. carolinianus (Bosc). The latter half of the
mantle is not distinguishable, but the transverse Ught
band followed by a dark band on the forward half
will readily separate it. Philomycus sellatus is the
common upland slug of northeastern Alabama and
adjacent Tennessee. It sometimes occurs with P.
carolinianus.

Illustrations by Miss Carole Wrigley provided
through the courtesy of Field Museum of Natural
History.

18

THE NAUTILUS

July 1972

Vol. 86(1)

A NOTE ON LAND SNAILS ASSOCIATED WITH KUDZU VINE

Dorothy E. Beetle

Peninsula Nature Museum

524 Clyde Morris Boulevard

Newport News, Virginia 23601

ABSTRACT

A heavy growth of Kudzu vine taking over a sandy slope and nearby woodland in
Newport News, Virginia, now supports a large population of land snails, consisting of
ten species. Among the genera represented are Triodopsis, Retinella, Hawaiia,
Ventridens, Zonitoides, Helicodiscus, Strobilops, Gastrocopta, and Vertigo.

On March 28, 1971 a fire raced along the north
boundary of the grounds of the Peninsula Nature
Museum in Newport News, Va. This area includes the
steep slope of a railroad overpass and adjacent forest
floor. This report lists the snails found exposed by
the complete removal of leaf litter.

Originally the land where the museum and the road
are situated was covered with a mixed pine and
hardwood forest. White and black oaks and hickories
are abundant and sweetgum, red maple, beech, tulip
tree and the shrubby dogwood and sourwood occur
in the area. The elevation is 45 feet above sea level.
The soil is coarse sand, with crossbedded sands,
gravels and clays extending downwards to
considerable depths. Newport News lies on a
peninsula which juts into the Chesapeake Bay. Its
climate is mild with abundant rain.

When the road and overpass were constructed in
1958, the steep sandy slopes were planted v/ith
Kudzu vine to prevent erosion. This rapidly formed a
dense mass which smothered volunteer plants. The
Kudzu has since invaded the adjacent woods. It has
smothered shrubs under festoons of vine and climbed
into the crowns of the tallest trees, killing them.
Under the trees scattered patches of moss, grass and a
few early spring flowers are the only plants which
survive.

In fall the Kudzu becomes dormant, leaving a
brittle mat of dead leaves resting slightly above the

soil on the vines which thickly crisscross along the
ground. These leaf mats can be lifted intact to view
the bare sand beneath. Even in the woods the sand
permits the rapid leaching of material and only a thin
humus layer is formed. Under the Kudzu vine
dessicated plant material consists almost entirely of
the previous year's growth. On the steep slopes of the
overpass the soil has almost no traces of plant debris.

In view of the exposed and Umited habitat of the
overpass, it was surprising to discover a large
population of land snails consisting of 10 species, plus
3 additional ones on the floor of the woods invaded
by Kudzu. The fire completely cleared the area of
plant material and the snails were picked up from the
surface of the sand.

STATION 1

One square yard, 35° slope, almost under the
overpass, 3 feet above ground level. The Triodopsis
and Gastrocopta were most numerous at this station.
One specimen of V. oscariana occurred here.
Triodopsis juxtidens
Retinella indentata paucilirata
Hawaiia minuscula
Ventridens cemoides
Zonitoides arboreus
Helicodiscus parallelus
Strobilops labyrinthica
Gastrocopta contracta
Vertigo oscariana

Vol. 86(1)

THE NAUTILUS

19

STATION 2
One square yard on low slope of embankment, one
foot above ground level.
Triodopsis juxtidens
Retinella indentata paucilirata
Helicodiscus parallelus
Succinea sp., juvenile
Gastrocopta contracta

STATION 3

Under standing dead trees, under and around log 4
inches in diameter.
Triodopsis juxtidens
Triodopsis fallax obsoleta
Triodopsis albolabris
Helicodiscus parallelus
Retinella indentata paucilirata
Hawaiia minuscula

Random collection from the forest floor also
turned up specimens of Mesodon thyroidus and

Ventridens cemoides. Triodopsis juxtidens was most
abundant all through the forest area; in some places
as many as a dozen individuals lying in one square
yard.

The woods in the vicinity of the nature museum
are second growth and receive fairly heavy use for
recreational purposes. While much of the understory
has been trampled down, the Kudzu vine has not yet
invaded this section. The same mollusks are present as
in the area of the Kudzu vine except for Succinea sp.,
Gastrocopta contracta and Vertigo oscariana. T.
juxtidens and//, parallelus are most abundant.

Gratitude is expressed for the assistance of F.
Wayne Grimm for identification of some of the
material.

LITERATURE CITED
Pilsbry, Henry A. 1940-1948 Land MoUusca of North
America (North of Mexico). Vols. 1-3. Acad. Nat.
Sci. Phila., Monogr. 3.

BOOK REVIEW

THE MARINE MOLLUSCS OF ARCTIC CANADA.

By Elizabeth Macpherson. PubUcations in Biolog-
ical Oceanography, no. 3. 149 pp., 54 maps, 7 pis.
Paperback. 1971. $3.50. Available by mail from
the Marketing Division, National Museums of
Canada, Ottawa 4, Canada.

This is a welcome handbook account of the shelled
marine mollusks of Arctic Canada exclusive of the
bivalves and cephalopods. Included are 1 08 species of
prosobranch gastropods, chitons and scaphopods.
Each species has its main synonymy, adequate de-
scription, Ust of Canadian localities, literature
records, overall range, distributional map, and an
accompanying photograph. There is a brief but

interesting discussion of the ecology and zoo-
geography of the mollusks of the Canadian Arctic. An
up-to-date bibhography and index are included.

The nomenclature is excellent, although a few
discrepancies have crept in. Lophyrochiton
Yakovleva, 1952, may be preceded by Stenosemus
Middendorff, 1847, and Lepidopleuroides Thiele,
1893. Buccinum tehue Gray, 1839 (non Schroter,
1805) should be scalariforme Moller, 1842. The
modern typography of the printed page, consisting of
alternating double and single columns and
not-too-clear photographs do not make this otherwise
excellent work easy to use.
R. Tucker Abbott
Delaware Museum of Natural History

20

THE NAUTILUS

July 1972

Vol. 86(1)

SEASONAL VARIABILITY IN CALYCULISM IN SPHAERIUM TRANSVERSUM (SAY)^

Waiiam F. Gale^

Department of Zoology and Entomology
Iowa State University, Ames, Iowa 50010

ABSTRACT

The nepionic shell of the freshwater bivalve, Sphaerium transversum, may be separated
from the older part of the shell by a sulcus, thus forming a bulging "cap " or caly cuius at
the umbo. Populations sampled from a stream in Iowa showed varying percentages of
specimens being calyculate or noncalyculate. Growth experiments in a field laboratory
indicated that arrested growth caused the formation of a calyculus, thus suggesting that
this character is of questionable taxonomic importance.

The calyculus or "cap" is the bulging upper
portion of the beak or umbo of some sphaeriid
shells. It consists of the shell of the nepionic young
(Thomas, 1965) and is separated from the rest of the
shell by a sulcus. While investigating the bottom
fauna of the Mississippi River near Fort Madison,
Iowa (Gale, 1969), I observed that some Sphaerium
transversum were distinctly calyculate and that others
were distinctly noncalyculate. Frequently, inter-
mediates were found in which the nepionic shell was
distinct, but not elevated above the surface of the
adjoining shell. Such shells were not considered
calyculate.

That S. transversum occurs in two forms has long
been recognized (Sterki, 1909). The significance of
the calyculus and why it is sometimes absent have not
been explained. Herrington (1968, personal commu-
nication) suggested that "capped beaks" might result
from a rest period. The presence of calyculi was a
characteristic used to justify the validity of
Musculium as a genus. Herrington (1962) suggested
that calycuh have little taxonomic value because they
occasionally occur in groups other than Musculium
and are variable within a species.

* Joumal Paper No. J-7035 of the Iowa Agriculture
and Home Economics Experiment Station, Ames,
Iowa. Project 1374. A contribution from the Iowa
Cooperative Fishery Unit sponsored by the Iowa
State Conservation Commission, Iowa State Univer-
sity of Science and Technology, and the Bureau of
Sport Fisheries and Wildlife (U. S. Department of
Interior). (Contract 14-16-0003-12204).
^ Present address: Ichthyological Associates,
Berwick, Pennsylvania 18603.

In bottom samples, the proportion of calyculate
clams diminished progressively between June and
September (Table 1). Similar trends occurred at
several sampling stations. Gams 2-3 mm long, with
the exception of those in May and December, usually
were not calyculate. Probably most of the clams 2-3
mm long had not grown since birth. Since the
calyculus represents the nepionic shell, it cannot be
observed until visible post-embryonic growth has
taken place. A few calyculate clams 2-3 mm long
were observed in the June-November collections, but
were missed in random selection of the subsamples.

In June, all clams examined were calyculate except
those 2-3 mm long. Most clams over 3.0 mm long in
June probably had over-wintered when 2-3 mm long.
In May only clams of the first two sizes were present
at station 14, the station where the June to December
samples were collected. Unless immigration occurred
at station 14 between May and June or unless the
samples were not representative, the small clams of
May grew into large calyculate clams by June. Thus,
clams that overwinter when 2-3 mm long, presumably
before growing, become calyculate as growth com-
mences the following spring.

In July, all clams 3-4 mm long and 30% of those
4-5 mm long were noncalyculate. These were prob-
ably born in June or July 1967. By August, non-
calyculate clams 6-7 mm long were beginning to
appear. A major die-off of calyculate clams in large
size classes occurred in August, and by September,
only noncalyculate clams remained. The absence of
calyculate clams at station 14 in September means
that the entire population consisted of clams born in
1967, probably since May.

Vol. 86(1) THE NAUTILUS 21

TABLE 1. Number of S. transversum examined (No.) in 1967 and percentage (%) with calyculate
shells. Specimens for April and May were pooled from 7 open-water stations about three
miles downstream from Ft. Madison, Iowa (Stations 4-10 on transect 3 of Gale, 1969).
Specimens for June through December were collected at a station about 0.5 miles further
downstream (transect 4 Station 14 of Gale, 1969). Clams 2-4 mm long were present in
April but were discarded after counting. When more than 10 clams were available for one
size group the specimens were randomly selected.

Size

Class

Apr

May

Jun

Jul

Aug

(mm)

No.

%

No.

%

No.

%

No.

%

No.

%

2- 3

~

—

10

80

10

0

10

0

10

0

3- 4

—

~

10

100

10

100

10

0

10

0

4- 5

3

33

10

90

10

100

10

70

10

0

5- 6

6

50

~

-

10

100

10

100

10

30

6- 7

10

10

2

100

10

100

10

100

10

70

7- 8

10

10

3

33

10

100

10

100

10

100

8- 9

10

0

3

33

10

100

10

100

10

100

9-10

9

0

2

50

10

100

10

100

1

100

10-11

2

0

-

-

10

100

10

100

1

100

11-12

2

100

1

100

Size

Class

Sep

Oct

Nov

Dec

(mm)

No.

%

No.

%

No.

%

No.

%

No.

%

2- 3

10

0

10

0

10

0

10

90

3- 4

10

0

8

75

10

50

—

_

4- 5

10

0

8

63

8

75

1

0

5- 6

10

0

10

40

6

100

~

--

6- 7

10

0

6

0

4

0

3

0

7- 8

10

0

10

0

6

17

1

0

8- 9

10

0

5

0

5

20

2

50

9-10

2

0

1

0

3

0

1

0

10-11

—

—

—

—

—

—

—

—

11-12

'

"

■

"*

"

22

THE NAUTILUS

July 1972

Vol. 86(1)

In October, calyculate clams reappeared, with
smaller clams becoming calyculate. During November
and December, the population included both
calyculate and noncalyculate clams. Of clams 2-3 mm
long, 90% were calyculate in December. Thus, over-
wintering is not essential for calyculus formation; but
all small clams that over-wintered became calyculate,
while only part of those bom between September and
December became calyculate.

The possibility that an initial period of no growth
(resting state) influences subsequent shell devel-
opment is plausible and is supported by growth
experiments conducted in a field laboratory during
1967 (Gale, 1969). In the laboratory most clams
which he d an initial lag in growth became calyculate
and those which grew immediately after birth became
noncalyculate. Therefore, the presence or absence of
calycuU in S. transversum is not hereditarily deter-
mined within the species. Thomas (1959) observed
that newborn S. partumeium reared in the laboratory
frequently exhibited a lag in growth lasting up to 6
weeks, but clams that grew immediately gave birth to
young that also began to grow immediately. Pre-
sumably, clams that did not grow immediately
produced young that had a growth lag.

The stimulus that eUcited a resting state in
laboratory-reared clams in my study, is not known,
but certain clues may be discovered by examining the
methods in which the clams were treated. Clams, in
chambers where growth lags occurred, were born in a
pan of river water, picked up with a camel-hair brush,
measured with an ocular micrometer, and placed into
a vial of river water until four were collected. The vial
of clams and water was then poured into the proper
chamber. Small clams in chambers where growth lags
did not occur were born there and were not measured
or otherwise handled until the chambers were cleaned
after 33 days.

Physical and chemical changes may have occurred
in the pan of river water holding the parental stock.
None of the newborn was in the pan longer than an
hour, but the process of gathering them from the pan
and making measurements consumed almost an entire
afternoon; ample time for changes in water temper-
ature, dissolved oxygen, pH, etc.

Tactile stimulation might have elicited a resting
state. Besides being handled with a brush, young were
frequently pushed about by larger clams in the pan.
That some young were born in the well-lighted pan
and others in subdued Hght in the laboratory may
have been important. That some chambers contained
the decomposing remains of the parental stock may
also have been a factor. Factors causing a resting state
in the laboratory and in the field may not have been
the same.

The presence of calyculi in part of the population
was helpful in assessing growth rates of the clams in
their natural environment. For example, if we assume
that the largest noncalyculate clams (4-5 mm long) in
July (Table 1) became the largest noncalyculate clams
(6-7 mm) in August, the mean length increase was
about 2 mm. Also, noncalyculate clams 3-4 mm long
in July grew to 5-6 mm in August. Since clams were
noncalyculate in September, growth of calyculate
clams can be followed in fall.

The results of this study substantiate Herrington's
(1962) contention that calyculism is of questionable
taxonomic importance.

I wish to thank Dr. Kenneth D. Carlander and Dr.
R. Jess Muncy, Department of Zoology and En-
tomology, Iowa State University, who directed the
research and made helpful suggestions concerning the
manuscript,

LITERATURE CITED

Gale, W. F. 1969. Bottom fauna of Pool 19,
Mississippi River with emphasis on the Ufe history
of the fmgemail clam, Sphaerium transversum.
Ph.D. thesis, Iowa State Univ., Ames, Univ. Micro-
film No. 69-20642, Ann Arbor, Mich.

Herrington, H. B. 1962. A revision of the sphaeriidae
of North America (Mollusca: Pelecypoda). Univ.
Mich. Mus. Zool. Misc. Publ. 118. 74 p.

Sterki, V. 1909. Some observations and notes on
Musculium, The Natilus 23: 17-19.

Thomas, G. J. 1959. Self fertilization and production
of young in a Sphaeriid clam. The Nautilus 72:
131-140.

Thomas, G. J. 1965. Growth in one species of
sphaeriid clam. The Nautilus 79: 47-54.

Vol. 86(1)

THE NAUTILUS

23

SHORT PAPERS

SUBFOSSIL NON-MARINE GASTROPODS FROM

MOLOKAI, HAWAIIAN ISLANDS

Patrick Vinton Kirch

Bernice P. Bishop Museum
P. 0. Box 6037, Honolulu, Hawaii 96818

Rapid extinction of endemic land snails in the
Hawaiian Islands has occurred due to massive removal
of native forests, particularly in lowland areas
(Carlquist 1970). Hence it is extremely difficult to
find associations of endemic gastropods in their
original habitats. Perkins (1913, pp. xxvi-xxvii)
long-ago recognized the importance of fossiliferous,
pulmonate-bearing deposits in the reconstruction of
lowland snail associations. In 1969 and 1970 I
studied a Holocene, non-marine gastropod bearing,
subfossil deposit at the base of Halawa Valley,
Molokai Island. The deposit (50-Mo-Al-4) is an
eroded taluvial fan (Wentworth 1943) comprising
unconsolidated sand, alluvial outwash, and slumped
material.

Charcoal from the base of the fan was submitted
to Gakushuin University, Japan, for radiocarbon age
determination. The result (GaK-2744) was 750 ± 90
B. P. (1950). The geologic matrix indicates that the
fossils were deposited with debris eroded from the
adjacent subvalley following extensive forest clearing
in prehistoric times.

Table 1 lists the gastropods (pulmonates and
prosobranchs) from this deposit. Apparently
originally they comprised a lowland snail association,
and as such allow a partial reconstruction of the
lowland flora as well. The probable habitat of these
snails is Ukely to have been dominated by Acacia koa,
Chenopodium sp., Eugenia sandwicensis, and small
stands of Metrosiderous sp. (an important pulmonate
host). Today the region is dominated by Leucaena
glauca, an introduced species.

Acknowledgements. I should Hke to thank Dr.
Yosiho Kondo for aid in the identification of
specimens.

Table 1 . Gastropods from A 1-4
Halawa Valley, Molokai Island

ENDODONTIDAE

Endodonta sp.
ACHATINELLIDAE

Tomatellinops baldwini ( Ancey)

Lamellidea gracilis (Pease)

Elasmias sp.

Tomatellides procerula (Ancey)

Tomatellaria cincta (Ancey)

AMASTRIDAE

Leptachatina emerita Sykes

Leptachatina varia Cooke

Amastra (Amastrella) petricola (Newcomb)

Amastra (s.s.) humilis (Newcomb)

Amastra (Heteramastra) perversa Hyatt and Pilsbry

SUCCINEIDAE

Succinea sp.

HELICINIDAE

Pleuropoma laciniosa var. molokaiensis Neal

LITERATURE CITED

Carlquist, S. 1970. Hawaii: A Natural History. The
Natural History Press, New York.

Perkins, R. C. 1913. Fauna Hawaiiensis 1(6), Cam-
bridge University Press.

Wentworth, C. K. 1943. Soil avalanches on Oahu,
Hawaii. Geol. Soc. Amer. Bull. 54: 53-64.

ODOSTOMIA TURRITA FOUND ON
HOMARUS GAMMARUS^

Jon-Ame Sneli

Biological Station, N-7001 Trondheim, Norway

Several species of molluscs belonging to the family
Pyramidellidae have been reported as ectoparasites of
other marine invertebrates (Robertson & Orr 1961,
Cheng 1967), but only one observation of a
pyramidellid in association with a crustacean has been
reported (Fretter & Graham 1949).

In October 1969 a lobster (Homarus gammarus
(L.) = H. vulgaris H. Milne Edwards) of 5.1 kg weight
was brou^t to the Zoological Museum in Oslo. The

^ Contribution No.
Trondheim, Norway.

1 56, Biological Station,

24

THE NAUTILUS

July 1972

Vol. 86(1)

lobster was collected at Herad near Farsund on the
Norwegian coast. On the pinching legs and carapace
were observed a few Pomatoceros triqueter (L.) and
by close examination of the gills one specimen of
Odostomia turrita Hanley was found. The
identification of the Odostomia species was kindly
done by Mr. Tore Hoisaeter. The O. turrita had to sit
weU-attached to the gills as the lobster was boiled,
transported and handled by fishmongers before
delivered to the museum.

O. turrita is distributed from the north of Norway
south to the Mediterranean, but no information
about its host-specifity has been reported. According
to Robertson & Orr (1961) the discovery of a
pyramidellid "on" or "with" another invertebrate
does not mean necessarily that the invertebrate in
question is host to the pyramidellid. The only reliable
records of parasitic relationships are those in which a
pyramidellid has been seen to feed.

Observation of feeding was in this case impossible,
but the record is still interesting as no earlier
observation of Odostomia species associated with
decapod crustaceans has been reported. Fretter &
Graham (1949) have seen O. plicata (Montagu) thrust
its proboscis onto the antennae of amphipods at
Plymouth but this behaviour may well have been
accidental (Robertson & Orr 1961).

Although the case remains to be proved there is no
reason to believe that the O. turrita found on the
lobster gill could possibly be associated with the few
P. triqueter located on the exoskelton of the lobster.

LITERATURE CITED

Cheng, T. C. 1967. Marine molluscs as hosts for
symbioses with a review of known parasites of
commercially important species. Adv. Mar. Biol. 5:
1-424.

Fretter, V. & A. Graham. 1949. The structure and
mode of hfe of the Pyramidellidae, parasitic
Opisthobranchs. J. Mar. Biol. Ass. U. K. 28:
493-532.

Robertson, R. & V. Orr. 1961. Review of
pyramidellid hosts, with notes on an Odostomia
parasitic on a Chiton. Nautilus 74: 85-91.

PYRAMIDELLID GENERA OF PILSBRY
James X. Corgan

Austin Peay State University
Clarksville, Tennessee 37040

H, A. Pilsbry proposed four genus-group names for
taxa he considered referable to the gastropod family
Pyramidellidae Gray, 1 840. Each name was proposed
for a new subgenus and each subgenus was charac-
terized in a few brief words or sentences appended to
a specific description. There was Uttle in PUsbry's
writings to indicate that the subgenera were new. As a
result, standard nomenclators Hke the Nomenclator
Zoologicus overlooked some of the names. Most were
also omitted from an excellent catalogue of Pilsbry's
taxa by Clench and Turner (1962).

Today, the genus-group names Pilsbry introduced
in the PyramideUidae are httle used because the
pyramidellid faunas he studied have received little
subsequent attention. His taxa have been overlooked
and have not been evaluated by modern workers.
Pilsbry's names are available names. The groups he
discriminated seem to be meaningful taxa. Several
could be widely distributed in the world fauna. This
report lists Pilsbry's pyramidellid genera and provides
a brief appraisal of each.

Evaletta PUsbry, 1918
Type Species - By original designation, rwrfton/7/fl
(Evaletta) elizabethae Pilsbry, 1918, p. 315.

Though it was described as a subgenus of Tur-
bonilla Risso, 1826, Evaletta and Turbonilla have
little in common. As interpreted by Dall and Bartsch
(1909) and by Laws (1937), Turbonilla has prom-
inent axial sculpture and an emergent, heterostrophic
protoconch. In Evaletta the heterostrophic proto-
conch is deeply immersed and there is no axial
sculpture. Species of Evaletta have more whorls than
most Turbonilla. The growth form is more acicular
and there is generally a weakly developed tooth on
the inner lip. Evaletta differs from Turbonilla in so
many characters that it should be ranked as a distinct
genus.

Only two species have been referred to Evaletta:
Turbonilla (Evaletta) elizabethae Pilsbry (1918, p.

314, fig. 9) and T (E.) laysaensis PUsbry (1918, p.

315, fig. 10). Both are Recent species from the
Hawaiian Islands.

Vol. 86(1)

THE NAUTILUS

25

Goniodostomia Pilsbry and Johnson, 1917
Type Species - By original designation, Odostomia
(Goniodostomia) superans Pilsbry and Johnson,
1917, p. 181.

Corgan (1971) catalogued the content of this
nominal genus and interprets Goniodostomia Pilsbry
and Johnson, 1917, as a junior synonym of
Eulimastoma Bartsch, 1916.

Nesiodostomia Pilsbry, 1918
Type Species - By original designation, Odostomia
(Nesiodostomia) prima Pilsbry, 1918, p. 325; non
Odontostomia acutiuscula var. prima Boettger, 1907
{= Nesiodostomia montforti Corgan, 1972).

The characters, content, and distribution of

Nesiodostomia are discussed at length by Corgan

(1972). Nesiodostomia has been recorded from the

Tertiary of Japan but this reflects confusion with the

morphologically similar genus Puposymola Coss-

mann, 1921. All species that are correctly referred to

Nesiodostomia are part of Recent faunas of the

Hawaiian Islands.

Odostomidea Pilsbry And Johnson, 1917

Type Species - By monotypy, Odostomia (Odos-
tomidea) bartschiana Pilsbry and Johnson, 1917, p.
182.

Odostomidea Pilsbry and Johnson was proposed as
a subgenus of Odostomia Fleming, 1813, but there
are few similarities between the two taxa. Species of
Odostomia lack sculpture while species of
Odostomidea are highly sculptured. In Odostomia,
the nuclear whorls are generally deeply immersed in
the first teleoconch whorl while they are about half
immersed in Odostomidea. The tabulate shoulder of
Odostomidea contrasts markedly with the smoothly
convex whorl profile of Odostomia. The two taxa
seem generically distinct.

Two species have been referred to Odostomidea
Pilsbry and Johnson: Odostomia (Odostomidea)
bartschiana Pilsbry and Johnson (1917, p. 152,
Ulustrated by Pilsbry, 1922, pi. 36, fig. 15) and O.
(O.) mogindo PUsbry (1922, p. 393, pi. 36, fig. 6).
Both were described from the Oligocene of Hispanola
and both bear a strong resemblance to Recent species
that have been referred to Salassia Folin, 1872,
Eupyrgulina Melvill, 1910, and Odostomella
Bocquoy, Dautzenberg, and Dollfus, 1883. A survey
of the hterature suggests that all of these nominal
genera need both taxonomic and nomenclatural
review. Until a comprehensive study is completed, it

does not seem possible to evaluate Odostomidea
Pilsbry and Johnson, 1917.

REFERENCES CITED
Clench, W. J., and Turner, R. D. 1962, New names

introduced by H. A. Pilsbry in the Mollusca and

Crustacea: Acad. Nat. Sci. Philadelphia, Spec. Pap.

4. 218 pp.
Corgan, J. X. 1971, Review oi Parodostomia, Telloda,

Goniodostomia, and Eulimastoma (Gastropoda:

PyramideUacea): The Nautilus 85, p. 51-60.
Corgan, J. X. 1972, Pacific species oi Nesiodostomia

Pilsbry, 1918, and Puposymola Cossmann, 1921

(Gastropoda: PyramideUacea): The VeUgerH p.,

355-360.
Dall, W. H., and Bartsch, P., 1909, A monograph of

the West American pyramidellid moUusks: U. S.

Nat. Mus. Bull. 68. 358 pp. 30 pis.
Laws, C. R., 1937, Review of the Tertiary and Recent

Neozelanic pyramidellid molluscs. No. 1. The

genus Turbonilla: Trans. Royal Soc. New Zealand

66, p. 402- 422, pis. 32-33.
Pilsbry, H. A., 1918, Marine Mollusca of Hawaii,

IV- VII: Proc. Acad. Nat. Sci. Philadelphia 69 p.

309-333, pis. 20-22.
PUsbry, H. A., 1922, Revision of W.M. Gabb's

Tertiary MoUusca of Santo Domingo: Proc. Acad.

Nat. Sci. PhUadelphia 73 p. 305-435, pis. 16-47.
PUsbry, H. A. and Johnson, C. W., 1917, New

MoUusca from the Santo Domingo OUgocene:Proc.

Acad. Nat. Sci. PhUadelphia 69 p. 1 50-205.

OBSERVATIONS ON THE SIPHONAL

BEHAVIOR OF YOUNG SURF CLAMS,

SPISULA SOLIDISSIMA

Morris K. Jacobson

American Museum of Natural History
Central Park West at 79th Street, New York 10024

Not many observations on the siphonal behavior of
the surf clam, Spisula solidissima (DUlwyn), in nature
appear in the literature. The foUowing account of
such an observation made in Rockaway Beach, New
York may therefore prove to be of interest.

During the September 1971 ebb rides, the sandy
area inhabited by large numbers of immature surf
clams was uncovered for a few hours each day. The
clams measured from about 40 to 80 mm (1^ to

26

THE NAUTILUS

July 1972

Vol. 86(1)

about 3 inches) in length. Dense patches of clams
were scattered throughout the sandy substrate. The
small openings of the siphons at the surface of the
sand were the only part of the clam that was visible.
Morse (1919:188) described these siphon openings.
He found 28 small papillae on the Up of the anal
(dorsal or excurrent) siphon, but they were not
readily visible under field conditions, and the opening
appeared as a small, rather narrow oval with
apparently smooth edges. The opening of the
branchial (ventral or incurrent) siphon was twice the
width of the anal siphon and was much distorted by
"two excessively stout papillae springing from the
wall in the conjunction with the anal syphon. They
are curved outward half-way across the opening. One
of these is bifurcated." (Morse, I.e.). The 33
irregularly alternating long and short papUlae fringed
the outer margin and were clearly seen. Frequently
both siphons were visible, but when only one
appeared, it was almost always the opening of the
dorsal siphon.

During the short inter-wave periods, when the sand
was not being roiled by the wave action, the siphon
openings were exposed. As a wave flowed in carrying
a thick suspension of sand grains, the siphon openings
closed and the presence of the animal was not
detectable for a moment. In the short interval when
the upsweeping wave came to a brief halt, the sand in
suspension sank rapidly to the bottom and
simultaneously the siphon openings appeared. As the
water receded, sand grains were again placed in

suspension and the openings again disappeared. As
the sand swiftly settled, the siphons opened again and
remained open until the next onrush of water.
Apparently the film of water remaining on the sand
surface before the next flow of water was sufficient
to enable the mollusk to continue its feeding and
elimination activities.

At more or less regular intervals a small jet of
water, thickly laden with sand grains, was ejected
from the ventral siphon. This behavior was typical of
clams inhabiting the active wash zone. As the tide
came in, observations had to come to an end, but it
can be assumed that in areas covered by the tide and
not within the wash zone, the surf clams kept both
siphons open constantly during its feeding periods.

The type of siphonal activity described for Spisula
is apparently a defensive adaptation to minimize the
ingestion of sand particles. Any sand taken in is
probably stored briefly in the branchial siphon and
expelled at certain intervals. It was surprising to note
that the anal siphon was open more often than the
branchial or feeding siphon.

This manuscript was kindly reviewed by Dr.
William K. Emerson of the American Museum and Dr.
John Ropes of the National Fisheries Service, Oxford,
Maryland.

LITERATURE CITED
Morse, E. S. 1919. Observations on Uving
lamellibranchs of New England. Proc. Boston Soc.
Nat. Hist. 35 (5): 139-196.

Dates of Publication of The Nautilus

Volume 85, number 1: July 20, 1971
Volume 85, number 2: October 4, 1971
Volume 85, number 3: January 27, 1972
Volume 85, number 4: April 28, 1972

INFORMATION FOR SUBSCRIBERS

The annual subscription rate for The Nautilus is
$7.00 for individuals and $12.00 for institutions
(domestic or foreign). Subscriptions may begin either
in January or, preferably, in July when a new volume
begins. Send check or money order to "The Nautilus"
to Mrs. Horace B. Baker, Business Manager, 11
Chelten Road, Havertown, Pa. 19083.

Back issues from volume 72 to date are obtainable
from the Business Manager. Volumes 1 through 71 (if
available) may be obtained in reprint or original form
from Kraus Periodicals, Inc., 16 East 46th Street,
New York, N.Y. 10017.

Advertising rates may be obtained from the
Business Manager or Editor.

CONTRIBUTORS

Manuscripts: Authors are requested to follow the
recommendations of the Style Manual for Biological
Journals, which may be purchased from the American
Institute of Biological Sciences, 2000 "P" Street,
N.W. Washington, D.C. 20036. Manuscripts should be
typewritten and doublespaced; original and one copy

are required, to facilitate reviews. Tables, numbered
in arable, should be on separate pages, with the title
at the top. Legends to photographs should be typed
on separate sheets. Explanatory terms and symbols
within a drawing should be neatly printed, or they
may be pencilled in on a translucent overlay, so that

the printer may set them in 8 pt. type. There is a
charge of 50 cents per word for this extra service. All
authors or their institutions will be charged 50 cents
per line of tabular material and taxonomic keys. The
pubhshers reserve the right, seldom exercised, to
charge $32 per printed page.

An abstract should accompany each paper.

Reprints and covers are available at cost to
authors. When proof is returned to authors,
information about ordering reprints will be given.
They are obtained from the Economy Printing Co.,
Inc., R. D. 3, Box 169, Easton, Maryland 21601.

NOVEMBER, 1972

THE

NAUTILUS

Vol. 86

Nos. 2 - 4

A quarterly

devoted to

malacology and

the interests of

conchologists

%» ^ '

0EC4 Wt
Woods Hoitt M|l»»

C-4<'

Founded 1889 by Henry A. Pilsbr/, Continued by H. Burrington Baker.
Editors: R. Tucker Abbott and Charles B. Wurtz

. - .;.. •■ .;'.-/ .:■ .'■ ■ ■>■■ ^

«,■■,•*■ <•

%.•,„'• ,. ■■>♦ V ' n "^ *.

EDITORIAL COMMITTEE

CONSULTING EDITORS

Dr. Arthur H. Clarke, Jr.
Department of Mollusks
National Museum of Canada
Ottawa, Ontario, Canada K1A-0M8

Dr. William J. Clench
Curator Emeritus
Museum of Comparative Zoology
Cambridge, Mass. 02138

Dr. William K. Emerson

Department of Living Invertebrates

The American Museum of Natural History

New York, New York 10024

Mr. Morris K. Jacobson

Department of Living Invertebrates

The American Museum of Natural History

New York, New York 10024

Dr. Aurele La Rocque
Department of Geology
The Ohio State University
Columbus, Ohio 43210

Dr. James H. McLean

Los Angeles County Museum of Natural History
900 Exposition Boulevard
Los Angeles, CaUfornia 90007

Dr. Arthur S. Merrill
Biological Laboratory
National Marine Fisheries Service
Oxford, Maryland 21654

Dr. Donald R. Moore

Division of Marine Geology

School of Marine and Atmospheric Science

1 0 Rickenbacker Causeway

Miami, Florida 33149

Dr. Joseph Rosewater
Division of Mollusks
U. S. National Museum
Washington, D.C. 20560

Dr. G. Alan Solem

Department of Invertebrates
Field Museum of Natural History
Chicago, Illinois 60605

Dr. David H. Stansbery
Museum of Zoology
The Ohio State University
Columbus, Ohio 43210

Dr. Ruth D. Turner

Department of Mollusks
Museum of Comparative Zoology
Cambridge, Mass. 02138

Dr. Gilbert L. Voss
Division of Biology

School of Marine and Atmospheric Science
1 0 Rickenbacker Causeway
Miami, Florida 33149

EDITORS

Dr. R. Tucker Abbott

Delaware Museum of Natural History
Box 3937, Greenville, Delaware 19807

Dr. Charles B. Wurtz
3220 Penn Street
Philadelphia, Pennsylvania 1 9 1 29

Mrs. Horace B. Baker

Business and Subscription Manager

1 1 Chelten Road

Havertown, Pennsylvania 1 9083

OFFICE OF PUBLICATION

Delaware Museum of Natural History

Kennett Pike, Route 52

Box 3937, Greenville, Delaware 19807

Second Class Postage paid at Wilmington, Delaware

Subscription Price: $7.00 (see Inside back cover)

i«nne Bmlogicai LuboratoryT"^

L/e/?>J|JPvNAUTl[.US

DEC 4 1972

CONTENTS

Hal Lewis

Notes on the Genus Distorsio (Cymatiidae) with Descriptions of New Species 27

Tadashige Habe

Notes on the Genus Parancistrolepis Azuma (Buccinidae) 51

Gale G. Sphon

Berthella kaiiiae, a New Opisthobranch from the Eastern Pacific 53

E. P. Cheatuni

A New Species of Humboldtiana (Helminthoglyptidae) from the Sierra Vieja Mountains of Texas 56

Winston F. Ponder and Gilbert P. Whitley

Tom Iredale (1880-1972) [an obituary] 60

Ronald F. Thomas and Frazier 0. Bingham

Shell Structure in Spirula spirula (Cephalopoda) 63

Joseph Rosewater and Geerat J. Vermeij

The Amphi- Atlantic Distribution oi Littorina meleagris 67

Joseph Rosewater

Teratological Littorina scabra angiilifera 70

Samuel L. H. Fuller

Type Locality of Unio pumilus Lea, 1 838 (Unionidae) 72

Samuel L. H. Fuller

Unio caroliniana Bosc, 1 801 (Unionidae) 74

Marc J. Imlay

Greater Adaptability of Freshwater Mussels to Natural Rather than to Artificial Displacement 76

(continued over)
i

Barry Roth and Richard E. Petit

A New Species o^ Persicula from the Arabian Sea (MarginelUdae) 80

Horace G. Richards

Quaternary MoUusks from Fiji 81

Hank K. Mienis

On the Alleged Occurrence of Lambis violacea and Clithon coronata in Indonesia 82

Tadashige Habe and Kiyoshi Ito

Ancistrolepis kawamurai, a New Japanese Buccinidae 83

Samuel L. H. Fuller

An Underscribed Structural Feature in the Marsupium oi Elliptic) lanceolata (Lea, 1828)(Unionidae) ... .85

Derek S. Davis

An Unusual Form of Littorina littorea (Linne) Found in Nova Scotia 87

News

Book Reviews

(of) R. T. Abbott. 50; B. R. Wilson and K. Gillett. 59; M. Furlong and V. Pill. 66; L. G. Hertlein and U. S.
Grant, 4th. 71.

NOTICE TO SUBSCRIBERS

In order to have a new volume of The Nautilus begin in January, rather than July, we have issued the
remainder of volume 86 in a combined issue of nos. 2, 3, and 4. For further information on billing, see p. 82.

11

Vol. 86 (2 - 4)

THE NAUTILUS

27

NOTES ON THE GENUS DISTORSIO (CYMATIIDAE) WITH

DESCRIPTIONS OF NEW SPECIES
Hal Lewis

Research Associate, Dept. Malacology

Academy of Natural Sciences of Philadelphia

Philadelphia, Pa. 19103

ABSTRACT

Distorsio perdistorta Fulton, 1938, whose known distribution has previously been
limited to Japanese waters, has been discovered in the Gulf of Mexico, the Lesser Antilles,
and the Indian Ocean. Distorsio horrida Kuroda and Habe, 1964, also originally limited to
Japanese waters, is a synonym A different species from Japan, misidentified by previous
workers as "perdistorta," is described as a new subspecies, Distorsio constricta habei
Lewis. The American tertiary progenitors of this species are believed to be D. crassidens
(Conrad, 1848) of the Oligocene and D. simillimus (Sowerby, 1850) of the Miocene. The
living species D. constricta is recognized as having three geographical subspecies - con-
stricta (Broderip, 1833) from the tropical Eastern Pacific; macgjntyi Emerson and Puffer,
1953, from the Western Atlantic; and habei, new subspecies from Japan. Similar subspe-
cific distributions are known among the Cymatiidae, Cassidae and Volutidae.

An unusual periostracal structure is described and illustrated along with various ana-
tomical features o/ Distorsio.

Distorsio burgessi is described as a new species from Hawaii which is sympatric with
Distorsio anus (Linne).

The lectotype of Distorsio ridens Reeve is figured and D. ridens is clearly separated
from D. reticulata /?oc?mg, D. perdistorta Fw/fo«, and D. decussatus Valenciennes.

INTRODUCTION

While examining shells in the collection of Mr. and
Mrs. Riley Black of Fort Myers, Florida, three spec-
imens of a Distorsio were brought to my attention.
These matched a specimen first sent to me by Mrs.
Elsie Malone of Sanibel, Florida, which had been mis-
identified as Distorsio macgintyi Emerson and Puffer,
1953. Surprisingly, these specimens proved to be in-
distinguishable from Distorsio perdistorta Fulton,
1938, a species living in Japanese waters which had
been renamed Distorsio horrida by Kuroda and Habe
in 1964. Unfortunately they also misidentified an-
other taxon known as "Distorsio perdistorta" Kuroda
and Habe, 1964, (not Fulton, 1938), which now re-
quires a new name.

This paper will confirm Distorsio perdistorta
Fulton as a vaUd species; substantiate its occurrence
in the Western Atlantic and the Indian Ocean; clarify
its history in the literature; differentiate it from Dis-

torsio clathrata (Lamarck, 1816) 2in^ Distorsio mac-
gintyi Emerson and Puffer, 1953, in the Western At-
lantic; and describe the taxon previously known as
"Distorsio perdistorta" Kuroda and Habe, 1964.

HISTORICAL DISCUSSION OF
DISTORSIO PERDISTORTA

Emerson and Puffer, 1953, in their catalogue of
the Distorsio suggested the possibility that perdistorta
is a geographical subspecies of Distorsio reticulata
Roding, 1798, and said, "Fulton states that this spe-
cies possesses affinities withZ). ridens {Rqqvq, 1844)"
which they considered to be a "variant of D. re/^/cw-
/a/a 'Bol ten' Roding, 1798."

An examination of reticulata and perdistorta has
shown that there are consistent taxonomic differ-
ences. Table 3 was prepared to facilitate a comparison
using characters which are helpful in separating Dis-
torsio. The list of differences cited in Table 3 and the

28

THE NAUTILUS

November 1972

Vol. 86 (2 - 4)

specific description of perdistorta contained in this
paper demonstrates that these are separate species.

Actually, Fulton (1938, p. 56) hsted various char-
acters which "separates this from ridem Reeve."
They are "the shorter anterior canal and the much
closer granular or reticulate spiral sculpture . . .; the
line of numerous small plaits on the anterior part of
the columella is perpendicular not oblique as in
ridens. " Examinarion of the lectotype, syntypes and

Reeve's figure shows that ridens is clearly separable
from perdistorta. D. ridens is regulariy fusiform,
while perdistorta is grossly distorted. There are 25 to
30 axial ribs on the body whori of perdistorta and
only 1 2 on ridens, giving it a much more open sculp-
ture.

The spiral cords of perdistorta are separated by a

fine interstitial cord which is lacking in ridens. The
parietal shield of ridens is medium-oval in shape with

TABLE 1. Specimens o/Distortio perdistorta examined from the Gulf of Mexico.

Length

Width

Locality

Depth

(mm)

(mm)

(meters)

82

44

Tampa, Florida

81

45

West of Fort Myers, Florida

183

79

43

West of Tampa, Florida

201

77

42

78

40

E.S.E. of Key West, Florida

274.50

67

36

66

35

64

36.5

59

32

36.5

21.5

75

42

110 miles S. W. Egmont Key, Fla.

155-183

69

38

W.S.W. Tampa, Florida

192

66

36

West of Fort Myers, Florida

183

57

32

West of Sarasota, Florida

174

The

"Blake" Caribbean Exploration J 878-79, USNM

20

12.5

Sta. 157

219

19

12.5

120 fms. off Montserrat

26.5

19

Sta. 282

282

19

11.5

1 54 fms. sand, near Barbados

13

7

Barbados

183

25.5

15.5

Barbados

133.5

30

18

40

28

St. Vincent

208.6

37

25

Barbados

172

broken

canal

Vol. 86(2-4)

THE NAUTILUS

29

Length
(mm)

Width
(mm)

Locality

Depth
(meters)

Japan:

72

40

Tosa, Shilcoku, Japan

183

64

35

63

35

61

35

46.5

26

40

22

63

33

Tosa, Shikoku, Japan

110

56

32

71

36

Tosa, Shikoku, Japan

110

71

38

Tosa, Shikoku, Japan

125

60

37

Sagami Bay, off Honshu, Japan

52.5

29

67

35

Kii, Honshu, Japan

62

37

54.5

30

Wakayama, Honshu, Japan

56

32

Madagascar:
60 34

43.5

20.5

P2. Chalutage 10

12°43'S-48°15'E

300-340

very coarse plicae along the columellar edge which
curve posteriorly away from the aperture past the
axis of the shell. The shield oi perdistorta is more ob-
long with finer teeth on the columellar edge which
are more or less in a straight line which ends at the
axis of the shell. (See Table 3 for a comparison be-
tween perdistorta, ridens, and reticulata).

Until now, Western Atlantic specimens of per-
distorta have been so rarely collected that they have
failed to come to the attention of those who have
worked with this genus. In 1951, Axel Olsson and
Thomas L. McGinty described Distorsio comtricta
floridana as a subspecies of the Panamic Distorsio
constricta Broderip 1833. Unfortunately, the name
had previously been used by Gardner (1947, p. 535,
pi. 53, fig. 8) for Personella floridana and it was nec-
essary for Emerson and Puffer (1953, p. 101) to re-
name it Distorsio mcgintyi. The spelling is here
emended to macgintyi to conform with the recom-
mendations on the formafion of names in Appendix
D of the 1961 Code. Among the material with which

Olsson and McGinty dealt were the Distorsio collect-
ed by the Blake expedition in the Gulf of Mexico,
1877-78 and in the Caribbean, 1879-80. While dis-
cussing the Distorsio in his well-known "Blake Re-
port", Dall (1889, p. 221) referred to Link's (1807,
p. 1 23) hst which limited the genus to two living spe-
cies. Dall stated that these were "the two species and
only two species of which it is composed, even at the
present day." While not mentioned by Dall, one of
these species was Distorsio anus (Linne, 1758), the
type for the genus, and the other was listed and dis-
cussed by him as Distortrix reticulata Link, 1807,
which is Distortio reticulata Roding, 1 798. Dall divid-
ed reticulata into "variety reticulata" and "variety
clathrata" and considered it to be the only species in
the Western Atlantic. Curiously, the taxon that Dall
considered to be "variety clathrata" is the subspecies
now known as D. constricta macgintyi, while what he
regarded as "variety reticulata" is actually Distorsio
clathrata {Lamarck, 1816).

30

THE NAUTILUS

November 1972

Vol. 86 (2 - 4)

Fig. 1, Protoconch o/Distorsio perdistorta,y4ca(iem'
of Natural Sciences of Philadelphia, 241660, 100 fms.
Tosa, Japan, height 2 mm.

The history and synonomy of A reticulata Roding
was discussed and clarified by Puffer (1953, p. 1 13).
The distribution of reticulata and anus is limited to
the Indo-Pacific.

Emerson and Puffer, 1953, and Clench and
Turner, 1957, limited the living species in the Western
Atlantic to Distorsio clathrata and Distorsio mac-
gintyi. Neither Dall nor later authors realized that the
"Blake" expedition had actually collected a third and
different species. I found seven specimens of this spe-
cies (four from the dry collection and three from the
alcohol collection) in the USNM. Some of these
proved to be the actual specimens listed by Dall as

"Distortrix reticulata" Link and were still labeled as
such. They match the holotype, and other specimens
of Distorsio perdistorta recently collected in the
Western Atlantic in every detail, including penis,
periostracum and operculum, althougli the shells are
smaller in size.

Examination of the literature of fossil mollusca
has failed to reveal any record of an ancestor of Dis-
torsio perdistorta in the Western Atlantic althougli
there is ample evidence of the ancestors of Distorsio
clathrata and Distorsio macgintyi. A special effort
was made to investigate the possibility that a Panamic
species, such as Distorsio decussata (Valenciennes,
1832), could prove to be a Panamic analog of Dis-
torsio perdistorta in either Recent or fossil form.
Woodring, (1928, p. 495, pi. 18, figs. 7, 8, 9) illust-
rates a mixture of species which he misidentifies as
"Distorsio decussatus simillimus (Sowerby, 1850)".
Figures 7 and 8 are actually Distorsio gatunensis
Toula. 1909, the fossil subspecies of Distorsio
decussata. Figure 9 is Distorsio simillima, the fossil
subspecies of constricta. The differences between per-
distorta and the living and fossil forms of decussata
suggest that a close relationship between the two spe-
cies is unlikely, in spite of their relatively close distri-
bution. This seems especially borne out when one ob-
serves the great similarity of Western Atlantic,
Japanese, and hidian Ocean specimens, in spite of
their extreme geographical separation.

Fig. 3, Left jaw of Distorsio perdistorta Fulton, Gulf
of Mexico, length: .75 mm.

Fig. 2, Radula of Distorsio perdistorta Fulton, 105
fms, WSW Tampa, Fla., width of rachidian: 120^.

Vol. 86 (2 - 4) THE NAUTILUS

TABLE 2. Specimens of Distorsio constricta habei Lewis, new subspecies, examined.

31

Length Width
(mm) (mm)

Locality

Depth
(meters)

53

28

Tosa Bay,

Shikoku, Japan

54
51
51
45

41

29
30

27
26

22

Tosa Bay.

Shikoku, Japan

53

28

Kii, Honshu, Japan

45
42

25

TO

Tosa, Shikoku, Japan

128

54

31.5

Tosa, Shikoku, Japan

128

TABLE

3. Con

iparison o/ Distorsio perdist

orta, Distorsio reticulata.

and Distorsio ridens.

perdistorta

reticulata

ridens

color
of shell

white;

cords can be
orange-brown

diffused tan;
cords can be
lighter

white;

some color on

axial ribs

shape of
whorls

rounded, very swollen
and distorted

tabled whorls above
angled periphery

rounded;

shell is fusiform

axial ribs

on body whorls

25-30

16- 20

13

plicae at

columellar

edge

fine, usually
formed in
straiglit line

fine, usually
formed in
straight line

gross, recurve
posteriorly away
from aperture

shape of
parietal shield

oblong

triangular to
rounded oval

medium oval

color of
shield

white or stained
orange-brown on
parietal area

solid dark tan

to pink

with white plicae

orange-brown with
white apertural edge;
to white

sculpture
of shield

smooth to low
coarse beading

fine beading
formed by ribs and
cords under shield

strong coarse beads,
axially aligned

plicae at

posterior

canal

absent or
very small

constricted; thir
tooth on inner e
of outer lip is
very prominent

2 large strongly
formed plicae

2 large strongly
formed plicae

shape of
aperture

d
dge

more open; third
tooth on inner edge
of outer lip is
sliglitly larger

constricted; third
tooth on inner edge
of outer lip is
very prominent

teeth at
inner edge
of
outer Up

9 to 10 large;
first tooth below
posterior canal is
usually double

8 to 9 large

6 to 7 large;
3 very small

32

THE NAUTILUS

November 1972

Vol. 86(2-4)

Fig. 4, Protoconch of Distorsio constricta habei
Lewis, height of protoconch: 1.8 mm.

Genus Distorsio Rbding, 1798

Distorsio Roding, 1798, Museum Boltenianum, pt. 2,
p. 133. Type species, Murex anus Linne, 1758,
subsequent designation J. E. Gray, 1847. (The
Latin noun distortio is feminine).

Description - Shells range in length from 25 to 90
mm. They are strongly sculptured with spiral cords
and axial ribs which can make them knobby or can-
cellated. The whorls are swollen and distorted be-
cause they bulge in order to accommodate the grow-
ing animal as it covers earlier whorls. There is a large
parietal shield which joins with an expanded
peristome to encircle the aperture. When partially
covered by new growth, the old parietal shields serve
as varices. The distorted whorls, parietal plicae and
grossly-formed denticles on the inner edge of the out-
er lip, create a very irregular aperture. The shield has
a groove and numerous irregular plicae on the lower
left. A short anterior siphonal canal usually turns up-
wards.

The radula is taenioglossate. It is situated in the tip
of an extremely long proboscis which lies folded in
the proboscis sheath (figs. 14 to 22). The proboscis is
capable of tremendous extension. This is typical of
the genus and quite different from the typical
cymatiid pleurembolic proboscis. In species which
have been examined, the jaws are small, transparent,
and not as strongly formed as in most genera of
Cymatiidae.

OPERCULA

Previous workers have suggested that the pattern
of the opercula of Distorsio varies intraspecifically be-
tween terminal (without a nucleus) and submarginal
(with a nucleus). Personal observation of numerous
broken and repaired opercula has indicated that there
is a high incidence of breakage and repair. This is
probably due to the difficulty of passing the
operculum through the extreme constriction of the
aperture. It is interesting to note that all of the
opercula of Distorsio which show clear evidence of re-
pair have a nucleus. Missing opercula are replaced by
newly formed ones, which also always have a nucleus.
1 have observed this characteristic change in pattern
from terminal (a-nuclear) to nuclear in the repaired
opercula of other genera of Cymatiidae such as
Cymatium s.s., Gyrineiim and Monoplex. Often the
growth rings depart from the semicircular arc which is
typical of the original terminal pattern. Furthermore,
the specimens which have remained terminal are
usually consistent in size and shape, while the nucle-
ated opercula vary considerably. When dealing with
perfect specimens of the opercula of Distorsio, the
primary muscle scar pattern and the shape delineated
by the varnish can prove to be a valuable taxonomic
character.

Distribution - Species of Distorsio are found in
most tropical portions of the world to a depth of 300

Fig. 5, Operculum of Distorsio perdistorta Fulton,
dredged WSW Tampa, Fla., 105 fms., height 9 mm.

hlg. 6, Operculum of Distorsio perdistorta Fulton,
Academy of Natural Sciences of Philadelphia,
241652, Tosa, Japan, height 7 mm.

I'ig. 7, Operculum of Distorsio perdistorta Fulton,
Academy of Natural Sciences of Philadelphia,
241652, Japan, height 6.9 mm.

Fig. 8, Operculum of Distorsio clathrata Lamarck,
140 ft. S.W. Cape San Bias, Florida, 1969, height 5
mm.

Fig. 9, Operculum of Distorsio constricta macgintyi
Fmerson & Puffer, South of Loggerhead Lt., Tor-
tugas, Fla., 25 fms., height 7.8 mm.

Fig. 10, Operculum (^>/ Distorsio habei Lewis, Acade-
my of Natural Sciences of Philadelphia, 189639, Tosa
Bay, Japan, 70 fms.. height 6 mm

Vol. 86 (2 - 4)

THE NAUTILUS

33

8

10

Fig. 5-10, Explanation on opposite page.

34

THE NAUTILUS

November 1972

Vol. 86 (2 - 4)

fathoms. The earliest American fossils of the sub-
genus Persunella appear to be from the Middle
Eocene, while the earhest Distorsio s.s. appears to be
Distorsio crassidens (Conrad, 1848), from the Oli-
gocene of Vicksburg, Mississippi

REMARKS ON THE SUBGENERA

Subgenus Rhysema Clench. Wm. J. and Turner.
Ruth D. 1957. Johnsonia, vol. 3, no. 36, p. 236. Type
species clathratus Lamarck, 1816, by original designa-
tion.

When Clench and Turner, 1957, described the sub-
genus Rhysema, they differentiated it from Distorsio
s.s. on the basis of two characters. They pointed out
that Distorsio anus, the type for Distorsio s.s., had a
parietal shield which "extends well above the upper
limits of the outer lip and covers the preceding two
whorls" and a siphonal canal which is "nearly verti-
cal." This limited Distorsio s.s. to one species and all
other living species were then considered to be in the
subgenus Rhysema. Up to the present day, there has
been no additional evidence to justify two subgenera.
It is true that the various species which comprise
Rhysema, do not have a parietal shield which covers
two preceding whorls, but the shield often covers one
preceding whorl and quite often exceeds the upper
limits of the outer lip. Furthermore, there are many
specimens of various species whose siphonal canals
are very recurved, although not vertical. These charac-
ters appear to be based upon differences of relative
degree. Wliile they miglit be considered valid when
separating species, they do not appear to define sep-
arate subgenera. A new species is described later in
tins paper which is very similar {o Distorsio anus. Be-
cause of this similarity most workers would agree that
it is properly placed in Distorsio s.s. The definition of
Rhysema would require placing it in Rhysema since
its parietal shield does not exceed the two preceding
whorls and its siphonal canal is not vertical. This
example alone demonstrates the difficulty one would
have in attempting to place the various species of Dis-
torsio into separate subgenera based on these charac-
ters.

As an added example, Distorsio clathrata differs as
much from Distorsio maegintyi as does Distorsio anus
from cither one. Distorsio anus is often considered a
shallow water species but. living specimens have been
found in 45 meters. While the various species of

Rhysema are considered to be from deep water, some
species have been found living intertidally. Until more
evidence becomes available, it seems unnecessary to
retain two subgenera which are so weakly differenti-
ated. Consequently, I consider Rhysema to be a syno-
nym oi Distorsio.

Distorsio perdistorta Fulton, 1938

Figs. 1,3, 5-7, 11-34

Synonomy -

1938 Distorsio perdistorta Fulton, Proceedings of the
Malacological Society of London, (March 16), vol.
23, pt. 1, pp 55-56, pi. 13, figs, 3 and 3a. Type
locahty; Kii, Japan. Type in the British Museum of
Natural History
1964 Distorsio (Rhysema) horrida Kuroda and Habe.
Shells of the Western Pacific in Color, vol. 2, p. 74,
pi 23, figs. 3 and 3 (both figures numbered 3).
Type locality, Tosa Bay, Shikoku, Japan. Type in
the National Science Museum, Tokyo, Japan.
Description - The largest shell examined reached
82 mm. in length. The color of the shell is white, but
pale orange-brown color may be present on the spiral
cords. There are 8 to 10 convex whorls producing a
spire of approximately 50°, The outer lip is thickened
with the outer margin curving forward. There are 8 or
9 denticles on the inner edge of the outer lip The
third denticle below the posterior anal canal is much
larger than the others and is opposite a deep indenta-
tion in the parietal wall, creating a constricted
apertural shape. The parietal shield is thin, rather ob-
long, being wider posteriorly and narrowing anterior-
ly. The shield can be smooth or sculptured with very
low spiral cords and axial ribs which form beads when
they cross. There are numerous irregularly formed
plicae on the left of the groove in the lower parietal
shield. These are variable in sculpture and number,
sometimes reaching the edge of the shield. The groove
itself is more open and straighter than in most species
of Distorsio. The siphonal canal is relatively straiglit
for the genus, short and turned slightly upwards. It is
bordered by 9 to 15 well-defined plicae, the greater
number usually occurring on the larger specimens.
The upper three plicae arc the largest and the re-
mainder diminish in size. The sculpture consists of 8
major spiral cords on the body whorl, the upper 5 or
6 being separated from one another by a single fine
interstitial cord. There are 8 or 9 varices with 20 to

Vol. 86 (2 - 4)

THE NAUTILUS

35

these papillae were
■i^'y'-^ky^ip^^-^':^^ y presumed missing

t

Fig. 11, Dorsal aspect of the mantle edge o/Distorsio
perdistorta Fulton (female) flattened to show papil-
lae.

Fig. 12, Dorsal aspect o/Distorsio perdisioita Fulton
(male). The mantle edge of this specimen lacks papil-
lae.

\

36

THE NAUTILUS

November 1972

Vol. 86 (2 - 4)

25 axial ribs between them which form beads when The operculum is small and distinct from that of

they cross and give the shell a reticulated appear- Distorsio clathrata although it is similar to Distorsio
ance. macgintyi (figs. 5 to 10).

exit of proboscis
sheath

proboscis

fully

retracted

proboscis sheath
opened dorsally

Fig. 13, Right lateral view o/ Distorsio perdistorta Fig. 14, £)orsa/ v/ew o/ Distorsio perdistorta Fw/ron.
Fulton.

Vol. 86 (2 - 4)

THE NAUTILUS

The soft body of the animal is tan, lacking the
spots typical of many Cymatiidae. The mantle edge
of the male animal examined was lacking in papillae
(fig. 12); however the female specimen has large ob-
vious papillae which are bisected by an open groove
(fig. 11). Since only two specimens were examined,
the differences in the mantle edge should not be con-
strued as evidence of sexual dimorphism. The penis is
very large with an open penial groove (figs. 12- 13),

The rachidian and laterals of the radula are very
powerfully formed (fig. 2). There is a long central
cusp on the racliidian with 4 to 6 sharply-pointed
shorter cusps on either side of it. The lateral has 6 to
9 small, sharply pointed cusps on the anterior lateral
edge. There are no cusps on the marginals. Because of
the extraordinary proboscis structure and the ex-
tremely small opening througli which the proboscis is
extended, the radula, jaws and buccal mass are very
small in relationship to the body mass,

PERIOSTRACUM

The periostracum is yellowish and formed in nu-
merous very low axial blades which are fringed with
fine projections along their edges. There are long
hair-Uke processes at the beads of the shell sculpture
which gives fresh specimens a bristly appearance. Al-
though the Japanese specimens of this species are
more sparsely bladed than the Western Atlantic spec-
imens, both exhibit an extraordinary periostracal
structure. Below the visible upper surface, there is a
second layer of tunnel-like chambers which run spiral-
ly around the shell (figs. 23 to 25). There is a perio-
stracal floor which is attached to the shell and a roof
which is parallel to the floor and shell surface. The
roof is formed by flat connections between the small
periostracal processes. The axial walls of the tunnels
are formed by the axial blades and the .spiral walls by
flat, vertical connections between the processes. I
have observed similar structures in Distorsio reticu-
lata, D. clathmta, A decussata, A constricta con-
stricta, and D. constricta macgintyt Two species
which do not have this type of periostracum are A
anus and A constricta habei.

DISTRIBUTION

The distribution of Distorsio perdistorta has pre-
viously been known from Tosa Bay, Shikoku, Japan
to Kii, Honshu, Japan. Based on the hmited amount

of material which has been collected in the Westeri.
Atlanfic, it is difficult to judge the relative rarity of
this species, but it certainly can be said that it has not
proved to be as common as Distorsio clathrata or Dis-
torsio macgintyt Thus far the northern record in the
Western Atlantic is west of Tampa, Florida, Gulf of
Mexico, while the southern record is off Barbados, in
the Lesser Antilles, Recently, two specimens were re-
corded from north-west Madagascar in the
Mozambique Channel, Indian Ocean.

COMPARATIVE FEATURES

Fulton described Distorsio perdistorta as white,
but examination of numerous specimens indicates an
occasional pale-brown coloration limited to the spiral
cords. This characteristic position of color pigment is
present in both Western Atlantic and Japanese spec-
imens, and appears to be a useful character in Dis-
torsio.

Some workers might be tempted to designate the
Western Atlantic representatives as a subspecies of the
Japanese perdistorta because of geograpliical separa-
tion, heavier periostracum and an apparent tendency
to reach a larger size. However, careful examination
of all the material failed to show that these were sig-
nificant differences. On the contrary, these characters
varied within each geographical range. My work with
the Cymatiidae has clearly demonstrated to me their
great ability for intraspecific variation. Laxton,
(1971), has shown that two distinct populations of
Cymatium spengleri (Perry 1811), can vary in spire
angle, number of varices, and other characters, when
each lives in different ecological situations and feeds
upon different species of ascidians which are available
in different quantities. Bayer, (1971, pp. 114-115)
discusses the close resemblance of various Japanese
and Caribbean genera and species. It is widely known
that other species of Cymatiidae are worldv^de in dis-
tribution with various unexplained geograpliical rela-
tionsliips. The morphological consistency of the
Japanese and Western Atlantic specimens of Distorsio
perdistorta makes it unnecessary to estabhsh a new
subspecies in spite of their great geographical separa-
tion.

In order to clearly differentiate the threQ Hving
species of Distorsio in the Western Atlantic, I have at-
tempted to estabhsh a diagnostic chart of their more
obvious differences.

38

THE NAUTILUS

November 1972

Vol. 86 (2 - 4)

TABLE 4.

Comparison of the three Caribbean

species of Distorsio.

Diatorsio

Distorsio

Distorsio

perdistorta

clathrata

const ricta

macgintyi

color

white;

brown;

dit't'used

cords

cords and ribs

light

orange-brown

white

orange-tan

shield

oblong;

oval-round;

oval-round;

shape

shallow or

strongly

strong white

no sculpture

sculptured

beads, color
in between

outer

relatively

strongly

raised

lip

smooth

denticulated

spiral cords

size

large;

large;

small:

to 82 mm.

to 90 mm.

to 55 mm.

spire

50°

55°

42°

angle

Distorsio constricta habei

new subspecies, Lewis

Figs. 4, 10,38,39

Synonomy -

1964 Distorsio ( Rhyscma) perdistorta Fulton,

Kuroda and Habc, Shells of Ihc Western Pacific in

Color, vol 2, p. 74, pi. 23, fig. 1 (non Fulton,

1938).

Description - The largest shell examined reached
54 mm. in length. There are 9 convex whorls which
have a Hallened plane above the periphery formed be-
tween the first and second spiral cords. The spire is
produced at approximately 42°. The outer lip is
slightly thickened with the outer margin curving for-
ward. There are 8 denticles on the right edge of the
aperture which extend to the edge of the outer lip
and form low cords. The third denticle below the pos-
terior anal canal is much larger than the others and is
opposite a deep indentation in the parietal wall. The

I'ig. 15-19, Dissection of the tip of the proboscis of
Distorsio perdistorta Fulton (dorsal aspect):

hni buccal mass;
c. esophagus;
ev. esophagal valve;
ie. incision in esophagus;

j. jaws positioned considerably posterior to lip of
oral tube;

lo. crenulated lip of oral tube (probably used for

ingestion of food);
Ip. lip of proboscis;
me. nmscles of the esophagal valve;

parietal shield is thin, oval and variably sculptured by
spiral cords and axial ribs which form low beads when
they cross. Color is a diffused pale orange-brown,
with more intense color limited to the spiral cords.
There is a clearly formed groove in the lower parietal
shield, bordered on the right by 8 to 12 denticles on
the columcllar edge of the siphonal canal, The first
denticle is the largest and the remainder diminish in
size. There usually is dcnticulation on the left side of
the groove, but in occasional specimens, the groove
blends into the parietal shield without delineating
dcnticulation. The siphonal canal is straight, short
and curves slightly upwards^ The sculpture consists of
8 major spiral cords on the body whorl and 3 cords
on the dorsal surface of the anterior canaL Between
the first and second cords below the suture, there are
2 or 3 fine interstitial cords The second and third
cords are close together with one fine interstitial cord
separating them. The third and fourth cord are sep-
arated by 2 fine interstitial cords, while the remaining

n.

buccal and labial nen^es;

o.

odontophore;

ot.

oral tube;

otl.

oral tube opened by longitudinal incision;

P-

proboscis;

r.

radula;

rni

retractor muscles;

sp.

surface of proboscis, opened by dorsal longitu

dinal incision;

tm

tensor muscles;

tp.

tip of proboscis;

Vol. 86(2-4)

THE NAUTILUS

39

Fig. 15-19, Explanation on opposite page.

40

THE NAUTILUS

November 1972

Vol. 86 (2 - 4)

(N

'■■^Ji

in

o
I/)

d)

(U

0)

(/)

u

(A

o

n

£1

o

4-1

^

ro

Q.

CD

X5
0)

I/)

*->
o

E

ro

o

^

u.

♦^

«^

a;

w

■D

>>

0)
I/)

•5*;;^

A.i;-^5

t

^

^ ^

^

to

to

in

*-4

<3

s

o

^

•*—

CO

S

^

?

bo

;u

■S

■^

c^

<i

s:

'^-mt

•

^
g

^

s

.0

^

c

«

s

CO

■c;

0

"a

t^

!3

s

cd

s:

CO

o

53

o

S5.

-t^

<;j

^**i

.23

53

"5

s

S

i-H

!ii

53

<u

c

in

"on

"^j

)-<

s:

a

O

o

5

-4— '

•"**»

"*^

C/3

CO

s:

s

§

-*-**

0

^

s

13

"ts

c

5^

1

«3

tn

"—4

s:

^

53

•*—

■C)

1>5

13

tn

-.^

«

■*~j

^ -s

•«:

-Q

2

<Nr

Ci.

on

0

-s;

bo

Vol. 86(2-4)

THE NAUTILUS

25 shell surface hollow chambers

Fig. 23, Single periostracal process o/Distorsio perdistorta Fulton.
Fig. 24-25, Details of periostracal structure o/Distorsio perdistorta Fulton, 125 fms. W. of Ft. Myers, Fla.

42

THE NAUTILUS

November 1972

Vol. 86 (2 - 4)

major cords are usually separated by a single fine
cord. There are 8 to 10 varices with 12 to 17 axial
ribs between the varices. Where the cords cross the
axial ribs, they form beads.

The periostracum is thin, yellowdsh, formed in
spiral rows which follow the cords of the shell in con-
trast to the numerous, fringed, axial blades of the
other species. There are thin, low hairlike processes at
regular intervals on the spiral rows and they align
axially. Longer processes develop on the ribs of the
shell The periostracum is attached directly to the
shell and lacks the second layer such as that found in
perdistorta and the other two subspecies, constricta
and macgintyU The operculum is terminal (fig. 10). I
have not examined an animal of this species.

Description of the holotype - The sliell measures
53 mm. in length and 28 mm. in width. There are 8
denticles on the riglit edge of the aperture which ex-
tend across the expanded peristome to the edge of
the outer lip, forming low cords. The lower left edge
of the parietal shield is lacking in denticulation. There
are 9 denticles on the columellar edge of the shield.
There are 1 5 axial ribs on the body whorl.

Distribution and type locality - Most of the spec^
imens which I have examined were taken in Tosa Bay,
Shikoku, Japan, which is designated the type locality.
There is one specimen from Kii, Honshu, Japan.
Kuroda and Habe list the distribution as Boso Penin-
sula, Honshu, to Tosa Bay, Shikoku, Japan at depths
of 100 to 200 m They state that the species is un-
common. The holotype is in the ANSP no. 325380;
four paratypes in ANSP 325381 ; one paratype in Del.
Mus. Nat Hist. no. 50943.

Differentiating features - Distorsio habei is Very
similar in general appearance to Distorsio constricta

and Distorsio macgintyi The differences are not sig-
nificant enough to justify specific separation. How-
ever, unlike the Western Atlantic specimens of Dis-
torsio perdistorta, they can be separated when the
three subspecies are compared. The taxononiic char-
acters wliich are consistent enougli to use are: pig-
mentation, the pattern of cords and interstitials, den-
ticulation on the expanded peristome and the struc-
ture of the anterior siphonal canal.

The shells of all three subspecies are irregularly
stained with orange-brown, but the cords on the shell
of habei are always colored v^th a darker pigmenta-
tion. On the parietal sliield of macgintyi and con-
stricta there are strongly formed white beads outlined
by a rich brown color in between the beads which
gives the shields a markedly reticulated appearance.
Tliis character is very consistent in macgintyi but
varies in some specimens of constricta. 1 have exam-
ined large specimens of constricta from the Galapagos
Islands which have no beading on the shield at all. All
of the specimens of habei examined had beaded
sculpture on the sliield, but the strength of the bead-
ing and color are variable, lower, and finer than the
beading and color on macgintyi The shield of habei is
either white or very liglit orange-brown. In some spec-
imens of habei, the parietal shield was well-below the
suture, but all of the specimens of constricta and
macgintyi which I have examined had parietal shields
which were at the suture or above it.

The regular pattern of interstitial cords which is al-
ways present in habei is absent from constricta and
irregularly variable when present in macgintyi In
habei, the riglit posterior edge of the anterior canal
slants toward the posterior columellar edge, almost
closing the canal externally at the point where they

Fig. 26-27, Distorsio perdistorta Fulton, Holotype, British Museum (Natural History), Kii, Japan, 60 mm. x 35
mm

Fig. 28-29, Distorsio perdistorta Fulton. Gulf of Mexico, 57 mm. x 32 mm.

l-ig. 30-31, Distorsio perdistorta, Fw/fow. West of Tampa, Fla. llOfms. The heavy periostracum on this specimen
is variable within the species. 66 mm x 36 mm.

I'ig. 32-33, Distorsio perdistorta Fulton. Tosa Bay, Japan, 63 mm. x 33 mm.

I'ig. 34, Distorsio perdistorta, Fulton. Dredged West of Tampa, Fla. This specimen has a periostracum that closely
corresponds to the average Japanese specimen. 82 mm. x 44 mm.

l-ig. 35, Distorsio clathrata Lamarck. Dredged 65 fms. offTortugas, Florida, 67 mm. x 36 mm.

I'ig. 36-37, Distorsio decussata, Valenciennes. Trawled near Topolobamp, Sinaola, Mexico, 40 fms. 64.5 mm. x
33 mm

Vol. 86 (2 - 4)

THE NAUTILUS

43

M. ' "-^'w->ii^>|3

jjHHj

^99IHH

■ - ■■'''^■\\^aBgm

^I^^^^^^^^^H^^^^I

^^^^■^^^^^^^^^^^V ^^^^^^^^^^^^^^^^^^^^^H

m >'<''*"]^^^V^

v^^^H^^^^^^^^^^H

^^^^^^^^H^^^^^HjF ^^^^^^^^^^^^^^^^^^^^^B

■ '-'''^^HPF'' -

: j^^B

m^ ^ss^m

^^KBb^ ^^iISI^^^I

^|k~- ■:i*f'

• ^^1

^^^x ■ s "^^^B

^^%

^^r S^H

^^^"' ^x^^a^l

Im

fll

^^^^■1^^^

■^^^^^^^^1

^^^Batr '"^^^Mv^k^^^^^^^^^

^^^^H

HfllH

j^^l^^H^^

Fig. 26-37, Explanation on opposite page.

44

THE NAUTILUS

November 1972

Vol. 86 (2 - 4)

come together. The edges of the anterior canals of
constricta and macgintyi remain parallel and leave the
canal open.

While discussing the holotype oihabei, I described
how the denticles on the right edge of the aperture
continue across the expanded peristome to the outer
edge of the shield, forming low cords. If the cords do
not continue from the apertural edge, there are no
denticles formed at the outer edge of the shield, al-
though there is a shallow groove which runs parallel
to the aperture down the length of the expanded
peristome. In both constricta and macgintyi, tliis
groove is stained with a darker orange-brown color.
Clearly defined denticles are formed on the right out-
side edge of the shield. Although separate, these
denticles align with those at the apertural edge.

In the specimens examined there were 8 to 13
axial ribs between the varices of constricta, (an aver-
age of 10.6); 11 to 20 on macgintyi (an average of
14.7); and 12 to 17 in habei (an average of 15.6).

Distorsio habei differs from Distorsio perdistorta
by being smaller, more distorted, having a more
angled whorl which is tabled above the periphery,
fewer axials (15.6) than perdistorta (20 to 25), a dif-
ferent pattern of interstitial cords, a different perio-
stracal structure and richer pigmentation than the
Japanese specimens of perdistorta. The spire angle of
habei is 42 while the spire angle of perdistorta is
50°.

HISTORICAL DISCUSSION OF HABEI

Kuroda and Habe in "Shells of the Western Pacific
in Color", (1964, vol. 2, p. 23, figs. 1 and 3) des-

cribed Distorsio horrida (their fig, 3) as a new species
and differentiated it from what they identified as
"Distorsio perdistorta Fulton" (their fig. 1). Exami-
nation of a photo of the type specimen of Distorsio
perdistorta kindly supplied by the British Museum of
Natural History and correspondence with Dr.
Tadashige Habe of the National Science Museum of
Tokyo proved that Distorsio horrida Kuroda and
Habe, 1964, is a synonym of Distorsio perdistorta

Fulton, 1938, and that "Distorsio perdistorta"
Kuroda and Habe (not Fulton) is an unnamed species.
This taxon is described as Distorsio constricta habei
in honor of Dr. Tadashige Habe whose many contri-
butions to malacology are known througliout the
world. Careful comparison of this species with spec-
imens of worldwide species of Distorsio has led me to
realize that Distorsio constricta habei from Japanese
waters along with Distorsio constricta constricta from
the Eastern Pacific and Distorsio constricta macgintyi
from the Western Atlantic are geographical sub-
species. These three subspecies give evidence once
again of the amazing distribution of some of the
Cymatiidae.

FOSSIL RELATIVES

There is some confusion in the literature that deals
with the ancestors of the recent Caribbean and
Panamic species of Distorsio, Various authors have
considered the Antillean Miocene fossil Distorsio
simillima (Sowerby, 1 850), to be a paleosubspecies of
three different recent Distorsio i.e.: decussata,
clathrata and constricta. The matter was further com-
plicated because they confused specimens of Dis-

Fig. 38-39, Distorsio constricta habei Lewis, Holotype, Tosa Bay, Shikoku, Japan, 53 mm. x 28 mm.

Fig. 40, Distorsio constricta macgintyi Emerson and Puffer, dredged 280 ft. S. W. of Key West, Fla., 43 mm. x 25

mm.

Fig. 41, Distorsio constricta constricta Broderip, dredged 200 m, off Southern Coast of Santa Cruz Is., Glalpagos,
49 mm x 27.5 mni

Fig. 42, Distorsio anus (Linne). Hawaii

Fig. 43-44, Distorsio burgessi Lewis, Hawaii, Holotype, The Academy of Natural Sciences of Philadelphia, No.
326470, 39 mm x 25 mm

Fig. 45-46, Distorsio ridens Reeve, Philippines, Syntype, The British Museum of Natural History, No. 1967630,
77.5 mm x 38 mm.

Fig. 47, Reeve's figure o/ Distorsio ridens.

Fig. 48, Distorsio ridens Reeve, Lectotype, American Museum of Natural History, 64.5 mm. x 35 mm

Vol. 86 (2 - 4)

THE NAUTILUS

iJ^^^sSf^s^.

Kpsn

P.

^^^^^^P*>v

A

S^SM

M^^^^B^

^m '^^^^^^^1

._ i

^^S^

^^^^H

.^A ^H

' ' ^^H

k^'W' ■

^^v^^p

I^^^H

■1 |K|fl

45

1 '

46

n

I .\

:p:m

47

F/^. 38-48. Explanation on opposite page.

46

THE NAUTILUS

November 1972

Vol. 86 (2 - 4)

torsio simillima with Distorsio gatunensis Toula, 1909
(Miocene, Panama). Rutsch, 1930, (pp. 6ia61 1, 614,
pi. 17, fig. 6) examined and figured the holotype of
gatunensis and concluded that this species is actually
the fossil form of the recent decussata. This was con-
firmed by Emerson and Puffer, 1953, (p. 100) and
Weisbord, 1962, (p. 271). Woodring, 1928, (p. 300,
pL 18, figs. 7 to 9) illustrates two species under the
name "Distorsio decussatus simillimus". Actually, fig.
9 and fig. 1, pi. 19, are a specimen of Distorsio
simillima, the ancestor of constricta. Figures 7 and 8
are Distorsio gatunensis Toula, the ancestor of
decussata. A possible sequence of evolutionary events
indicates that the first true Distorsio s.s. was
crassidens (Conrad, 1848), Vicksburg, Mississippi,
Middle Oligocene, which spread throughout the
Caribbean developing into simillima during the Mio-
cene and eventually into the recent macgintyi,
Pilsbry, (1922, p. 360,) considered crassidens to be a
fossil subspecies of Distorsio constricta. However, he
was unaware of the existence of macgintyi, since that
species was not reported until 1951, and he was
under the impression that simillima had died out in
the Caribbean without a recent form. Fossil evidence
shows that simillima existed in the Tertiary Caribbean
faunal province from the Lower Miocene to the Plio-
cene and in the Eastern Pacific from the Middle Mio-
cene to the Pliocene. It must be remembered that the
Tertiary Caribbean Province extended into the East-
ern Pacific from southern Nicaragua to northern Peru.
Woodring, (1966, p. 427) suggests the possibility of
transportation of planictonic larvae by the Miocene
North Equatorial current along the south border of
the Canbbean Sea, through the Atrato Strait (and
others) into the Eastern Pacific. It has been reason-
ably established that this faunal migration was at its
heiglit during the Middle Miocene, a time which
corresponds with the fossil presence of simillima in
the Eastern Pacific. Since simillima was unknown in
the Eastern Pacific during the Lower Miocene, we can
assume that it existed in the Caribbean province for
approximately 5 million years before migration into
the Eastern Pacific. It is likely that Distorsio
macgintyi was the first recent species to develop from
the crassidens-simillima stock. Distorsio simillima,
having migrated to the Eastern Pacific during the Mid-
dle Miocene, became isolated at the end of the Terti-
ary and early Pleistocene after closure of the Central
American land bridge, and there was modified into
the present-day constricta. Eastern migration of an-

cient simillima accounts today for the Japanese sub-
species Distorsio constricta habei

Distorsio burgessi new species, Lewis
Figs. 43, 44

In August, 1963, an unidentified species of Dis-
torsio was illustrated by Dr. C. M. (Pat) Burgess on
the first page of vol. 1 1, no. 10, of the Hawaiian Shell
News. The specimen appeared to be closely related to
Distorsio anus Linne and until recently I have con-
sidered it to be a polymorphic form of A anus. Re-
cently sufficient material has come into my posses-
sion to show that consistent differences do exist be-
tween the two species which suggests that they are
sympatric.

Distorsio anus is widespread in its distribution and
shows morphological variation within a given popula-
tion as well as between widely separated populations.
However, there is such a great intergrading of form
that it would be impossible to tell where a given spec-
imen was taken. In the case of Distorsio burgessi, its
distribution is hmited to Hawaii and though found
with D. anus, it can readily be separated from it.
Tliough D. anus is very common and D. burgessi rela-
tively rare, large selections of anus examined which
were taken in the same general area as burgessi fail to
show specimens which intergrade with burgessi The
first specimen illustrated in Hawaiian Shell News was
taken, along with two others, in 14 fathoms, but the
holotype and paratypes were found by diving in shal-
lower depths, dispelling the idea that burgessi might
be a deep water form of anus. The differences be-
tween the two species are consistent but do require
careful observation. If the species were not sympatric
it would seem more reasonable to consider burgessi as
a subspecies of anus.

Distorsio burgessi is named in honor of Dr. C. M.
Burgess who first published it as an unidentified spe-
cies.

Description - The largest shell examined reached
60 mm. in length. There are 9 convex whorls which
have a flattened plane above the periphery formed be-
tween the first and second spiral cords„ The periphery
is defined by the second and third spiral cords joining
to form a double cord The spire is produced at an
angle of approximately 53°. Tlic outer lip is fonned
by the right edge of the parietal shield which projects
slightly past the' body whori. Behind the shield at the
point where it rneets the body whori there is a strong
axial cord which is separated from the preceding axial

Vol. 86(2-4)

THE NAUTILUS

cord by a deep groove. Tliis groove is crossed by the
spiral cords and gives the impression of a deep perfor-
ated line. The outer edge of the parietal shield is shal-
lowly ruffled by 9 low cords which are separated by 8
dark brown shallow grooves. Larger specimens have a
row of sharply formed teeth at the beginning of each
dark groove arranged in a line parallel to the outer Up.
These teeth are separated from the apertural denticles
by a secondary groove which is also parallel to the
outer lip and is liglitly stained in a dotted line be-
tween the teeth. The parietal shield is the most strik-
ing character of this species. It is ear-shaped, and the
lower left edge of the shield is flattened and conforms
to the body whorl behind it. The main mass of the
shield is sculptured by 9 strong, regular, spiral cords
and 5 or 6 axial ribs wliich create a checkerboard pat-
tern This effect is greatly enhanced by the rich
dark-brown pigmentation in the grooves between the
squares of the pattern. An unusual appearance is cre-
ated along the left and upper edges of the parietal
shield because the ribs stop before the left edge and
the spiral cords continue, while the cords stop before
the upper edge and the axial ribs continue. The aper-
ture is typically irregular and with 9 denticles. The
third, wliich is the largest, is opposite a deep indenta-
tion in the parietal wall. The shell is wliite, liglitly
stained with a very pale orange. The columellar phcae
and siphonal canal are straiglit and aligned on the axis
of the shell. The siphonal canal is very short and re-
curves dorsally at an angle of approximately 115°.
The sculpture consists of 8 spiral cords on the body
whorl and one cord on the dorsal surface of the
siphonal canal. There are usually 10 to 12 major axial
ribs which cross the cords and form low nodules^ The
periostracum is yellowish, very flat and thin, formed
in a regular pattern of low hairlike processes, with
slightly larger processes forming on the axial ribs. It is
attached directly to the sheU surface, lacking the
second layer found in perdistorta. I have not exam-
ined an animal nor the operculum of this species.

Description of the holotype - The shell measures
39 mm. in length and 25 mm in width. There are 12
denticles along the columellar edge to the end of the
siphonal canal. There are 12 major axial ribs on the
body whorl. The specimen has its periostracum in-
tact. Holotype ANSP no. 326470. 2 paratypes in the
Hal Lewis collection. 1 paratype Del. Mus. Nat. Hist.
1 paratype in the CUfton So Weaver collection.

Distribution - All of the specimens examined were
taken in Hawaii at approximately 21.1 8N Long.
158.07 W. Lat. off Oahu Island, Type locality:
Barber's Point, S. W, Oahu Island, Hawah. Collected
by E.

Differentiating features - This species differs from
Distorsio anus primarily on characters relating to the
parietal shield and anterior siphonal canal. The parie-
tal shield of Distorsio anus is oval to almost round
with deep ruffles usually present around the peri-
meter of the shield. It rises above the body whorl to
completely cover the preceding two whorls. In Dis-
torsio burgessi the ruffled edge is restricted to the
outer lip and the shield covers approximately Wi pre-
ceding whorls. The shield of anus is white to diffused
orange-tan, lacking the rich dark-brown pigmentation
typical of burgessi. The sculpture on the shield of
both species consists of 9 spiral cords but on anus
there are usually more numerous axial cords, giving
the shield surface a finer beaded and wrinkled look.
Even when the sculpture is coarser, it lacks the regu-
lar checkerboard pattern of burgessi. The anterior
canal of anus is always angled to the left, often curv-
ing slightly, in contrast to the straiglit axially aligned
canal of burgessi. The siphonal canal of anus is longer
and recurves dorsally at an angle of approximately
90°. The groove to the left of the siphonal canal on
the lower left parietal shield of anus opens into the
aperture via a secondary groove which is framed by
two large plicae. All of the specimens of burgessi
which were examined did not have this secondary
groove, and the primary groove in the lower left
shield was reduced, thinner and shallower than in
anus, forming a narrow dark-brown passage which fol-
lows the edge of the columellar-siphonal denticles. In
specimens examined, there were 10 to 12 axial ribs
on burgessi and 14 to 16 axial ribs on anus.

In spite of the rich pigmentation present on the
parietal shield of burgessi, it is lacking in the rich
body whorl pigmentation typical of Distorsio anus.
This appears once again to be an indication of the
specific importance of the position of pigmentation
on the shells of Distorsio.

Dis torsio ridens Reeve, 1844

Figs. 45-48

In the course of my work with the Cymatiidae, I
have observed that the species known as ridens Reeve
is often misidentified in collections. This very uncom-

48

THE NAUTILUS

November 1972

Vol. 86 (2 - 4)

mon species has had equal inistreatment in the litera-
ture. It has been listed as reticulata Roding (Maxwell
Smith, 1948, p. 23); properly figured but misidenti-
fied as reticulata (Wagner and Abbott, 1967, p. 85,
fig. 13-11 5); been confused with Distorsio smithi von
Maltzan, 1884 (Nickles 1950, p. 86, fig. \2>3),perdis-
torta Fulton, 1938 (Oyama, 1957, pi. 1, figs. 7-8),
and, in many other instances too numerous to men-
tion, improperly synonymized, misidentified and mis-
figured. The actual species described and figured by
Reeve (1844, Triton, pi. 12. sp. 46) has been subse-
quently figured properly by Try on (1881, pi. 17, fig.
177) and Webb (1935, pi. 51, fig. 10). Both of these
figures are copies of Reeve's original figure, and it is
probable that neither author had actually seen spec-
imens of the species. Oddly enough, I have been un-
able to find a published photograph of rid ens.

A recent visit to the British Museum of Natural
History to study types revealed that none of the
syntypes labeled ridens matched the actual specimen
figured by Reeve. It is important to realize that
Reeve's cymatiid drawings are accurate depictions of
the specimens which they represent, matching them
very well in size, color pattern, details of breakage,
etc. All of the syntypes were less colorful, and none
matched the figure in size, although they were clearly
the same species (fig. 45). However, there is a spec-
imen in the collecfion of the American Museum of
Natural History New York (cat. no. 6369) (fig. 48)
which so very closely matches Reeve's figure (our fig.
47) that I feel it is reasonable to designate it as the
lectotype. The specimen measures within a millimeter
of the figure, matches it exactly in the outline of the
shell, shape of the parietal shield, position of color
(absent from the syntypes), spire angle, broken
siphonal canal, number of denticles on the columellar
edge and minor details of breakage. The only differ-
ences appear to be artististic exaggerations of a
sece)nd row of plicae on the lower left parietal shield
and the gross manner in which the groove on the low-
er parietal shield enters into the aperture. Both of
these characters are unique to the figure, being absent
from the syntypes and all other specimens examined.
1 have never seen characters such as these on any
specimen of any species of Distorsio. This specimen is
from the Wm. A. Haines collection, the bulk of which
was given to the AMNH in 1879. Haines, an American
conchologist of the 19th Century, exchanged with
many famous conchologists of the day, and could
have obtained the specimen through his friend John

C. Jay, or even directly from Reeve. While at the
British Museum of Natural History, I carefully exam-
ined every cymatiid in the collection, including ma-
terial not separated and distributed. There were no
other specimens of ridens Reeve that could be con-
sidered to match the figured specimen.

The ridens situation is further complicated by the
similarity of ridens to Distorsio decussata
Valenciennes, 1832. There is a claimed "paratype" of
ridens in the collection of the Museum of Compara-
tive Zoology at Harvard University (MCZ 186600 C.
B. Adams coll.) with Philippine data but which actu-
ally is a specimen of decussata. This misidentification
is common. Distorsio decussata can quickly be sepa-
rated from ridens by the fact that decussata always
has a double spiral cord at the periphery, a character
which is consistent in fossil as well as Recent spec-
imens. Myra Keen (1971, p. 508, sp. 962) lists the
range of decussata from Cape Tepoca and Guaymas,
Sonora, Mexico, south to Manta, Ecuador, offshore
to depths of 82 m., and she properly considers Dis-
torsio ridens of authors, not Reeve, to be a synonym
of decussata.

It is hoped that the discussion of this matter, pub-
lication of photographs of the lectotype, syntype and
Reeve's figure will serve to clarify this species and es-
tablish it as a valid taxon, separable from reticulata,
per distort a and decussata.

ACKNOWLEDGEMENTS

I wish to thank Dr. George Davis, Associate Cura-
tor, Department of Malacology of the Academy of
Natural Sciences of Philadelphia for his valuable criti-
cal comments on the manuscript; Dr. R. Tucker
Abbott, du Pont Chair of Malacology. Delaware Mu-
seum of Natural History, who initially suggested that
this paper be written and greatly assisted in its organi-
zation and nomenclature; Dr. Robert Robertson,
Pilsbry Chair of Malacology, Academy of Natural
Sciences of Philadelphia, for his suggestions and dis-
cussion of the manuscript; The British Museum of
Natural History. MoUusca Section, for their kind co-
operation during my visit, and Mrs. Way for the
photo of the holotype of Distorsio perdistorta: Dr.
William Emerson, Chairman of the Department of
Living Invertebrates, American Museum of Natural
History of New York, for drawing my attention to

Vol. 86 (2 - 4)

THE NAUTILUS

4>

certain references in the literature of fossils; Dr.
Joseph Rosewater, Division of Mollusks, National Mu-
seum of Natural History, Washington, D. C, for his
kind cooperation and the loan of valuable material;
Dr. Robert Bullock, Museum of Comparative Zoology
at Harvard College, for the loan of valuable material;
and to Dr. Tadashige Habe, Curator of Invertebrate
Zoology, National Science Museum, Tokyo, for his
kind cooperation and correspondence.

LITERATURE CITED

Bayer, Frederick M. 1971. Biological Results of the
University of Miami Deep-Sea Expeditions. 79.
New and Unusual Mollusks Collected by R/V John
Elliott Pillsbury and R/V Gerda in the Tropical
Western Atlantic. Bulletin of Marine Science. 21
(1): 11-236, figs. 1-72. Coral Gables, Fla. (Univer-
sity of Miami Press) (March).

Broderip, W. J. 1833. Proceedings of the Zoological
Society of London, pt. 1, p. 5.

Clench, William and Turner, Ruth. 1957. Johnsonia,
Monograph of the Western Atlantic Mollusks, The
Family Cymatiidae in the Western Atlantic 3 (36):
1 89-244, 26 pis. (December 20).

Conrad, T. A. 1848. Observations on the Eocene
Formation, and Descriptions of One Hundred and
Five New Fossils of that Period, from the Vicinity
of Vicksburg, Mississippi; with an Appendix. Jour-
nal of the Academy of Natural Sciences of
Philadelphia 1, ser. 2, p. 188, pi. 11, fig. 40.

Dall, WUliam Healey 1889. Reports of the Results of
dredging ... by the U. S. Coast Survey Steamer
"Blake", pt. 2, Gastropoda and Scaphopoda. Bul-
letin of the Museum of Comparative Zoology, 18:
492 pp., pis. 10-40 (June).

Emerson, William K. and Puffer, Elton L. 1953. Cata-
logue of the Mulluscan genus Distorsio (Gastro-
poda, Cymatiidae). Proceedings of the Biological
Society of Washington 66: 93-108 (August 10).

Fulton, H. C. 1938. Descriptions and figures of new
Japanese Marine Shells. Proceedings of the Mala-
cologjcal Society of London 23 (1): 55-56, pL 3,
figs. 3 and 3a (March).

Gardner, JuHa 1947. The Molluscan Fauna of the
Alum Bluff Group of Florida. U. S. Geological
Survey Professional Paper, 142-H, pt. 8: 493-656,
pis. 52-62.

Habe, Tadashige Dr. 1964. Shells of the Western
Pacific in Color. 2, 233 pp., 65 pis.

Keen, A. Myra 1971. Sea Shells of Tropical West
America, p. 508, figs. 962 & 963.

Laxton, J. U. 1970. Shell growth in some recent New
Zealand Cymatiidae. Journal Exp. Marine Biology,
vol. 4, pp. 250-260.

Lamarck 1816 - Tableau Encyclopedique et
Methodique, Liste, p. 4, Atlas 3, pi. 413, figs. 4a
and 4b.

Link, H. F. 1807. Beschreibung der Natur-
alien-Sammlung der Universitat zu Rostock.

Nickles, Maurice 1950. Mollusques testaces marins de
la Cote occidentale d'Afrique. Manuels Ouest-Afri-
cains, 2: 86 & 87, fig. 133.

Olsson, A. and McGinty, T. L. 1951. A Distorsio new
to the Florida Fauna. The Nautilus, Philadelphia
65(1): 26-28, pi. 1, figs. 5, 6, 10, 11, 12 (July).

Oyama, Katura 1957. The Molluscan Shells, Science
and Photography Club, Distorsio 1, figs. 1-12.

Pilsbry, Henry A. 1922. A Revision of W. M. Gabb's
Tertiary Mollusca of Santo Domingo. Proceedings
of the Academy of Natural Sciences of Philadel-
phia 73, pis. 16-47.

Puffer, Elton L. 1953. Distorsio reticulata vs. Dis-
torsio clathrata in the West Indies. Proceedings of
the Biological Society of Washington 66: 109-124,
pis. 6 and 7 (August).

Reeve, Lovell A. 1 844.. Conchologja Iconica 2, Tri-
ton, pis. 1-20.

Rutsch, R. von 1930. Einige interessante Pag-
stropoden aus dem Tertiar der Staatem Falc6n und
Lara (Venezuela). Eclog. Geol. Helve tiae, 23 (2):
604-614, pi. 17.

Smith, Maxwell 1948. Triton Helmet and Harp Shells,
p. 23, pi. 8, fig. 10.

Sowerby, G. B. II 1850. Descriptions of new species
of Fossil Shells found by J. S. Heniker Esq. The
Quarterly Journal of the Geological Society of
London, pt. 1, Proceedings of the Geological Soci-
ety 6: 44-53, pis. 9-10.

Toula, Franz 1909. Fine jungtertiare Fauna von
Gatun am Panama-Kanal. Jahrbuch der Kaiser-
lick-Konigliehen Geol. Reichsanstalt, pp. 673-760,
4 pis.

Valenciennes, A. 1832 (in) Humbolt and Bonpland.
Recueil d'Observations de Zoologje et d'Anatomie
Comparee 2: 306-307.

von Maltzan, Hermann Freiherrn 1884. Diagnosen
neuer Senegambischer Gastropoden. Nachrichts-
blatt der deutschen Malakozoologichen Gesell-
schaft, no. 5, pp. 65 & 66.

50

THE NAUTILUS

November 1972

Vol. 86(2-4)

Wagner, Robert J. L. and Abbott, R. Tucker 1967,
Von Nostrand's Standard Catalog of Shells. Second
Ed., p. 85, fig. 13-115.

Webb, Walter Freeman 1935. Handbook for Shell
Collectors, Sixteenth Ed., p. 105, pi. 51, fig. 10.

Weisbord, Norman E. 1962. Late Cenozoic Gastro-
pods from N. Venezuela. Bulletin of American Pa-
leontology, vol. 42, no. 193 (March 5).

Woodring, Wendell P. 1928. Miocene MoUusks from
Bowden, Jamaica, Part 2. Gastropods and discus-
sion of results, no. 385, 564 pp., 40 pis. (Carnegie
Institute of Washington Pub.).

Woodring. Wendell P. 1966. The Panama Land Bridge
as a Sea Barrier. Proceedings of the American
Philosophical Society, vol. 110, no. 6, pp.
425-433, 4 tables.

BOOK REVIEW

THE KINGDOM OF THE SEASHELL by R. Tucker
Abbott. Crown Publishers, Inc., 419 Park Avenue
South, New York, New York. 256 pp., 92 black
and white plates, 1 78 colored plates and 13 draw-
ings. 1972, $14.95.

This delightful book presents a whole spectrum of
topics on marine mollusks from their division into six
classes to how and where to find them; their breeding
habits, structure, coloration and the ways in which
they have been used in the arts, religion and history.
Certain families, such as the volutes, cowries, murices,
cones and scallops, are selected to portray their im-
portance to man.

Many of the colored plates are among the finest
illustrations that have ever been published in this
field. These, as well as the black and white photo-
graphs, were gleaned from several sources; all are ac-
knowledged at the end of the book. This volume is

not a textbook on mollusks, even though it contains
much general and basic information, but rather a por-
trayal of the many facets of this remarkable group of
animals. Dr. Abbott has an unusual ability to grasp
those facts which are important and interesting about
seashells and to combine them all in a lively book
which reads like a novel. It is essentially a book for
the uniniated, but moUusk enthusiasts, whose efforts
have been devoted largely to collecting shells, will
find much to broaden their views. Anyone who ap-
preciates a well-written, artistically arranged book
will want to own one.

The book is fully indexed and contains a useful,
selected bibliography, the titles being grouped under
appropriate subject headings.

William J. Clench

Curator Emenitus

Museum Comp. Zoology

Vol. 86 (2 - 4)

THE NAUTILUS

NOTES ON THE GENUS PARANCISTROLEPIS AZUMA (BUCCINIDAE)

Tadashige Habe

National Science Museum, Tokyo, 160, Japan

The genus Parancistrolepis was established by
Azuma in 1965 for Japelionf?) kinoshitai Kuroda,
1931, because of the remarkable radular features,
which superficially resemble the radula of the family
Fasciolariidae rather than that of the family Buccini-
dae in having a three-cuspidate central tooth and a
eight-to-nine-cuspidate marginal tooth.

This genus was also assigned Ancistrolepis fujitai
Kuroda, 1931, by him, only because of the shell char-
acters and the extremely small operculum which
closely resembled those of the type species. This spe-
cies differs from the type species by its thick velvety
periostracum on the surface and in being surrounded
by prominent spiral cords. Ancistrolepis hiranoi
Shikama, 1962, is an absolute synonym o{ A. fujitai
Kuroda.

The writer has observed and figures here the radu-
lae of Parancistrolepis kinoshitai (Kuroda) and
Ancistrolepis fujitai Kuroda tentatively assigned to
the genus Parancistrolepis by Azuma. These two spe-
cies have the same radular formula, suggesting they
belong to the same genus as follows:

In Parancistrolepis kinoshitai, the central tooth is
subquadrate in shape and has three small cusps at its
hind margin and the marginal tooth is large and trans-
versely broad and has eight to ten cusps.

In Ancistrolepis fujitai, the central tooth has four
small cusps and the marginal tooth 14 cusps just as
does the type species.

The radula o{ fujitai does not agree well with that
of the genus Ancistrolepis Dall, 1895, in spite of the
close resemblance of its shell features. Therefore, we
assign it io Parancistrolepis Azuma, 1965.

An examination of the anatomy o{ Ancistrolepis
grammata (Dall, 1 907) shows the radula of the genus
Ancistrolepis has a four-to-six-cuspidate central tooth
and a four-cuspidate marginal tooth. Unfortunately,
the radula oi Ancistrolepis eucosmia (Dall, 1891), the

type species of the genus Ancistrolepis, has never
been examined.

The genus Parancistrolepis is a peculiar group in
having the thin shell ornamented by prominent spiral
cords and covered by a thick periostracum, in having
an extremely small operculum, and by its marginal
tooth having many cusps. These features are far apart
from the related subfamilies Neptuneinae and Ancis-
trolepisinae. I therefore estabhsh a new subfamily
Parancistrolepisinae.

Fig. 1. Parancistrolepis fujitai (Kuroda) from off
Kushiro, Hokkaido Island, Japan,

52

THE NAUTILUS

November 1972

Vol. 86 (2 - 4)

LITERATURE CITED

Azuma, M. 1965. On the Radulae oi Ancistrolepis

kinoshitai (Kuroda) and A. trochoideus ovoideus

Habe & Ito. Jap. Jour. Malac, Venus 24(2):

127-129, text figs. 1-2.
Habe, T. & Ito, K. 1965. Shells of the World in color,

vol. 1 (The North Pacific) 176 pp., 56 pis.

Hoikusha, Osaka.
Kuroda, T. 1931. On the Japanese Species of the

Chrysodomid Whelk, Ancistrolepis and Japelon.

Venus 2(5): 221-234, text figs. 1-18.
Shikama, T. 1962. On some Noteworthy Shells from

off Chosi, Chiba Prefecture. Sci. Rep. Yokohama

Natl. Univ., (2)8: 29-86, pis. 1-3.

Fig. 2. Half row of radula of Parancistrolepis fujitai
(Kuroda) from off Kushiro, Hokkaido Island, Japan.

Fig. 3. Radula of P. kinoshitai (Kuroda) from En-
shunada, Honshu Island, Japan,

Vol. 86 (2 - 4)

THE NAUTILUS

53

BERTHELLA KANIAE, A NEW OPISTHOBRANCH FROM

THE EASTERN PACIFIC

Gale G. Sphon

Los Angeles County Museum of Natural History
Los Angeles, Calif. 90007

ABSTRACT

Berthella kaniae Sphon, a member of the opisthobranch family Pleurobranchidae, is
described as a new species from Isla Siboga, Perlas Islands, Panama (type locality) and
Punta Mita, Nayarit, Mexico. It is close to B. sideralis (Loven) and B. californica (Dall).

A new species of Berthella was collected by the
author from Punta Mita, Nayarit, Mexico, in 1960,
and through the kindness of Mrs. K. B. Meyer of the
Smithsonian Tropical Research Institute in Panama, a
second specimen was obtained from the Perlas Is-
lands, Panama. I take great pleasure in naming this
species for her.

Berthella kaniae new species
Figs. 1-8

Description - Ground color translucent, ranging
from deep yellow to almost white. Color more in-
tense on dorsum; fading along edges of mantle. Tips
of frontal veil, rolled rhinophores, and area around
genital aperture colored reddish brown. Notum, gill,
sides and frontal veil spotted with same reddish
brown color. Notum (of holotype) covered with
white powdering seen only under 10 magnification,
SheU located mid-dorsal area, wholly internal, thin,
delicate, translucent, white; haliotiform in shape.
Ventral side of shell iridescent. Umbo small, spire of
two small whorls. Sculpture of very fine irregular
growth lines radiating from umbo region and showing
through shell. Gill rachis smooth; 18 leaves on the
dorsal half. Genital opening simple without lobule; lo-
cated in front of gjll. Radula 80 rows with 100-105
teeth per half row. No rachidian tooth. Dental formu-
la, 80(100-105.0.105-100). Teeth equal in size for en-
tire half-row except for the outermost 3 or 4 which
get progressively smaller. Curve of hook of individual
lateral teeth remains constant. Mandibular plates v^th
approximately 58 rows and about 37 platelets per

row. Scales of platelets approximately equal-size ex-
cept for the outermost 4 or 5 which become pro-
gressively smaller. No denticles or barbs on the plate-
lets.

Type material - Holotype: California Academy of
Sciences Invertebrate Zoology Type collection no.
560 consists of the entire animal and an egg mass that
was laid after the specimen had been collected from
15-30 feet, Isla Siboga (type locality), Perlas Islands,
Panama, by Joyce Young on February 15, 1972. It
measured 13 X 6.5 mm. when alive and fully relaxed.
The preserved animal measures 9 X 5,5 mm. Color
transparencies of the holotype (CASIZ slide col-
lection 2741) and of the paratype (CASIZ slide col-
lection 2742) have also been deposited with the
California Academy of Sciences. Both photos were
taken of the animals in life. Paratype: Los Angeles
County Museum of Natural History, Invertebrate
Zoology type collection no. 1453 consists of the
shell, a radula slide and a sUde of the jaw plates. The
paratype was collected by the author in 2 feet of
water on the underside of a dead coral head at Punta
Mita, Nayarit, Mexico, on January 21, 1970. Color
transparencies of both the holotype and paratype
have also been deposited at the Los Angeles County
Museum of Natural History,

Discussion - There are two other species of
Berthella known to occur in the eastern Pacific:
Berthella sideralis (Loven, 1846) and Berthella cali-
fornica (Dall, 1900). The simplest, and most arfificial,
way to separate B. kaniae from these two species is
on the basis of distribution and color. Berthella

THE NAUTILUS

November 1972

Vol. 86 (2 - 4)

t »

• •

*i

**' 4»

V

.>

m:

w

'^aSi.-w"*'

V%

.'.1 - 1

8

Vol. 86(2-4)

THE NAUTILUS

'^'^

sideralis was originally described from the Norwegian
coast and later collected by Dall (this was questioned
by MacFarland. 1966) from 25 fathoms off Unalaska,
Alaska. Bcrthella califoruica ranges from Crescent
City, Del Norte County, to La JoUa, San Diego Coun-
ty, California. Berthella kaniae is a tropical-sub-
tropical species found in Nayarit, Mexico, and the
Perlas Islands, Panama. Both B. sideralis and B. cali-
fornica are white in color. Berthella kaniae has a yel-
lowish ground color and is tipped and spotted with
red dish- brown.

Illustrations by MacFarland (1966. pi. 13) show
the median lateral radular tooth o{ Berthella sideralis
to be thin, narrow and have a slight bend at the tip.
This varies along the half row to rather short, stubby,
hooked innermost teeth. The outermost teeth have
only a shght bend and no hook at the end of a long
narrow tooth. MacFarland's illustrations (from Bergh,
1904) for the radular teeth o{ Berthella californica il-
lustrate almost sickle shaped teeth. Berthella kaniae
has little variation along the entire half row of teeth,
but the teeth are sharply hooked. None of the three
species appear to have serrations on the teeth mar-
gins.

The mandibular platelets of all three species are of
comparable shape, but those of Berthella sideraUs are
serrated while both B. californica and B. kaniae are
smooth. The shells of all three species are comparable
in form.

Acknowledgments - I am extremely grateful to
Mrs. Kaniaulono B. Meyer for supplying the holotype
specimen, photo and data which made it possible to
complete the description. I also wish to thank Mr.
David K. MuUiner for permission to use his photo-
graph of the paratype.

On May 19, 1972 (after the original submitting of
this paper) a third specimen of Berthella kaniae
Sphon was found in 15 feet of water at Isla Siboga,
Islas de las Perlas, Bay of Panama. The animal was
nestled in a crevice on the underside of a small clump
of the coral Pocillopora sp. and as it was being pried
out with a knife, it autotomized a large piece of the
notal border. By the time the animal was removed, a
second piece had been cast off so that the whole
notal border (about half the entire notum) was miss-
ing from the animal. Figure 1 of the holotype clearly
shows that that specimen had also autotomized its
notal border. Although the phenomena of autotomy
appears frequently in the nudibranchs and saco-
glossans as a defensive mechanism, to my knowledge
this is the first report of it occurring in the pleuro-
branchs.

LITERATURE CITED

Bergh, L. S. R. 1904. Malacol. Unters. Semper Set. 9,

6(3): 119-181.
Dall, W. H. 1900. A new species o{ Pleurobranchus

from California. The Nautilus 14 (8): 92-93.
Loven, S. L. 1846. Index Moll. Litora Scand. Occi-

dentalis habitantium. Ofvers. Kgl. Vet. - Akad.

Forhandl. 3: 136-140.
MacFarland, F, M. 1966. Studies of opistho-

branchiate mollusks of the Pacific coast of North

America. Mem. Calif. Acad. Sci. 4: 1-546.

Figs. 1-8. Berthella kaniae Sphon, new species. Fig 1, Holotype (CASIZ 560, X7). Fig 2, Paratype (LACM
1453). Fig. 3, Shell of paratype, dorsal view (X7.5). Fig. 4, Shell of paratype, ventral view(X7.5). Fig. 5, Group
of mandibular platelets (from paratype). Fig. 6, Single mandibular platelet (from paratype). Fig. 7 , Pair of lateral
teeth (from paratype). Fig. 8, Single lateral tooth (from paratype).

56

THE NAUTILUS

November 1972

Vol. 86 (2 - 4)

A NEW SPECIES OF HUMBOLDTIANA (HELMINTHOGLYPTIDAE)
FROM THE SIERRA VIEJA MOUNTAINS OF TEXAS

E. P. Cheatum

Department of Biology, Southern Methodist University,
Dallas, Texas 75222

ABSTRACT

Humboldtiana fullingtoni Cheatum, a new pulmonate species, and the tenth species of
this genus recorded from the Texas Trans-Pecos mountainous area, is described from
5,000 ft., southern end of the Sierra Vieja Mountains, Presidio Co., about 40 miles SSW
of Valentine, Texas. It is closest in shell morphology to H. hoegeana praesidii Pilsbr)'. Its
soft parts are grayish brown, while those of other Texas species in the genus are yellow,
orange or golden. Significant distinguishing characters in the genus are discussed.

Humboldtiana fullingtoni new species
Figs. 1,2,3

Description of holotype - Shell rather thin, subglo-
bose and slightly depressed; ornamented by three,
wide dark-brown bands on the basal whorl; two bands
at the beginning of the penult whorl, the lower of
these two fading out, thus leaving only the upper
band which gradually fades out about one-half turn
from the embryonic whorls. Width of the bands on
basal whorl (measured just back of the hp): upper 4.0
mm.; middle 4.3; and lower 4.6. With the exception
of rather close-set growth lines, some of which are
marked with whitish streaks and splotches, shell
smooth and devoid of distinct granulations, although
under high power very minute granulations are visi-
ble. Inner basal portion of peristome strongly reflect-
ed over the umbilicus in the form of a slightly
rolled-over triangular plate. Narrow umbilical chink
not visible from a direct apertural view. Embryonic
whorl convex and the initial one-half embryonic
whorl smooth; following whorl marked with minute
irregularly-arranged radial and sliglitly curved striae.
Inner lip sHghtly thickened; ground color of inner
apertural wall the same wood-brown of outer shell
and broken by dark bands on the basal whorl. Shell
height: 31.2 mm.; diameter: 38.6 mm.; apertural
height: 23.6 mm.; apertural wddth: 21.2 mm.; spiral
angle: 122° (using Parodiz measuring methods,
1951); sutural angle: 2°; columellar angle: 15°; 4
whorls.

3

FIGS. I, 2 and 3, Humboldtiana fullingtoni Cheatum,
new species. Holotype, 31.2 mm. in height, 38.6 mm.
in width. Apical views of \\. ferrissiana /^//^. 4) and H.
chisosensis (fig. 5).

Vol. 86 (2 - 4)

THE NAUTILUS

57

Living animal uniform fuscous. When withdrawing
into the shell the animal discharges a considerable
quantity of a clear, frothy viscous substance. The ani-
mal when full> extended measured approximately 65
mm. in length.

Holotype: No. 2186 - 5A Dallas Museum of Natu-
ral History; paratypes M.C.Z.; USNM 706882; Univer-
sity of Michigan Museum of Zoology; Carnegie Muse-
um; and the Academy of Natural Sciences of Philadel-
phia.

COMMENTS

The new species, Humboldtiana fullingtoni, was
collected April 20, 1971, at an altitude of approxi-
mately 5,000 ft. along the rimrocks overlooking the
Rio Grande River near the southern end of Sierra
Vieja Mountains in Presidio County, Texas. The type
locality is situated about 40 miles south-southwest of
Valentine, Texas.

^0^^' "'""^M

8

FIGS. 6-9, Apical views of Humboldtiana cheatumi
(fig. 6), edithae (fig. 7), H. agavophila (fig. 8), and H.
fullingtoni /"/ig. 9).

The snail-collecting expedition was conducted
under auspices of the Dallas Museum of Natural His-
tory, Mr. Hal Kirby, Director. The first Humboldtiana
were discovered by Mr. Richard Fullington, Curator
of Invertebrates at the Museum and I am naming this
species in his honor. Most of the ten living snails and
twenty-four "bones" collected were found at depths
of one and one-half to over three feet between and
beneath rocks. The living snails were attached to
rocks and the dead shells were dug out of dirt and
humus at the above depths. The soil and humus even
at these depths were powder-dry since the last rainfall
received in that area had occurred the preceding
September. Some of the living snails had secreted as
many as four apertural epiphragms in order to pre-
vent water loss.

In size this new species conforms with four other
species - H. edithae Parodiz which was collected on
Mt. Emory in the Chisos Mountains, H. agavophila
Pratt, collected at Laguna Meadow just west of Mt.
Emory, H. cheatumi Pilsbry collected in the Davis
Mountains; and, (in the collections at the Dallas Mu-
seum of Natural History two shells) H. chisosensis
Pilsbry which measure 39 mm. in diameter. The latter
were collected by Mr. E. H, Miner in 1951, but the
precise locality in the Chisos range was not given. As
more shells of Humboldtiana are collected, undoubt-
edly the size range of the various species will be ex-
tended.

Although the color bands of H. fullingtoni show
considerable variation in width, all are dark-brown in
color. In one large, partly broken, fresh shell the in-
terspace between the middle and lower bands is whit-
ish and this wide whitish area extends around the
basal whorl. This shell, compared with other speci-
mens collected at the same place, exhibits extreme
variation in the width of color bands. Measurements
of the bands (just back of the Hp): upper, 3.7 mm.;
middle, 1.7; and lower 6.3. Such variation precludes
the use of color band width as a distinct taxonomic
feature. In all the other shells the ground color is of a
uniform light-brown with the exception of the whit-
ish streaks and splotches which are irregular in distri-
bution.

According to Pilsbry 's (1939) description of H.
hoegeana praesidii, H. fullingtoni conformed closer to
this subspecies than any other species described for
the genus. Since I had not had the opportunity of
examining the type of//, hoegeana praesidii {U. S. N,

58

THE NAUTILUS

November 1972

Vol. 86 (2 - 4)

TABLE 1. Measurements ofParatypes in mm.

Diameter Height Aperture Heiglit Apertural Width

36.0

30.15

18.8

90 0

35.8

31.3

18.25

22.4

37.5

32.6

22.8

19.0

37.1

31.8

20.7

22.6

38.0

31.2

19.9

23.2

36.5

31.1

18.3

21.4

35.2

31.7

18.8

21.4

35.8

29.8

19.1

20.6

38.1

33.6

24.5

23.5

Whorls

4

31/2
3^i
3-M

y/i
31/2
31/2
yA
4

M. 134160), I asked Dr. Harald Rehder, Senior
Zoologist, Division of Mollusks at the U. S. N. M. to
compare a paratype of H. fuUingtoni with the type
shell of//, hoegeana praesidii. After a careful exam-
ination of the two shells, Dr. Rehder made the fol-
lowing comments (Correspondence, June 29, 1971):
"Your species is indeed closer to this subspecies than
to any other Texas form . . . The apical whorls of//.
fuUingtoni do show under high power fine riblets that
are faintly granulated in places. On the third whorl
these granules increase in strength and then on the
penultimate whorl they disappear. In H. hoegeana
praesidii this granulation appears to be much more
obscure, thougli our specimens, including the type,
are rather worn and this granulation may have been
rubbed off. Your new species is furthermore larger
and darker in color, with the bands wider than in H,
hoegeana praesidii ' ',

Apical views of H. ferrissiana, H. chisosensis, H.
cheatumi, H. edithae and //. agavophila (figs. 4, 5, 6,
7 and 8 respectively) show the distinct shell granula-
tions in contrast to Fig. 9 of H. fuUingtoni in which
granulations are absent.

In living snails of the Texas Humboldtiana which
we have had the opportunity to examine, all have had
various parts of the body either a yellow, orange or
golden color. The color of the living animal of //.
fuUingtoni is a uniform fuscous or grayish brown.

When considering shell characteristics of the vari-
ous species of Texas Humboldtiana it seems that the
most reliable distinguishing characters to be used are
the presence or absence of visible granulations, shape
of the granulations, smoothness or ornamentation of
the embryonic whorls, their shape (flat or rounded),
ground and band color of the shell and shell angles.

Shell color and markings must be based upon fresh
shells. In old shells the periostracum is so frequently
eroded so as to completely obliterate granulations
and other distinctive shell markings.

Ten species of Humboldtiana have now been
described from the mountainous areas of the Texas
Trans-Pecos, and these are the following Pilsbry
(1939):

Humboldtiana chisosensis Pilsbry
Humboldtiana ferrissiana Pilsbry
Humboldtiana hoegeana praesidii Pilsbry
Humboldtiana cheatumi Pilsbry
Humboldtiana palmeri Clench and Rehder
Humboldtiana texana Pilsbry
Humboldtiana ultima Pilsbry

Pratt (1971), described Humboldtiana agavophila
from the Chisos Mts.; Parodiz (1954) described //i/m-
boldtiana edithae from Mt. Emory in the Chisos Mts.;
and this species, Humboldtiana fuUingtoni is the
tenth species to be described from the Texas
Trans-Pecos. Pilsbry (1927), had listed//, chisosensis,
H. texana and H. ultima from Texas. In his key, based
upon shell characters, the major breaks involved
granulations and whether or not the shell was
smoothish or with wrinkles along the growth lines. //.
hoegeana praesidii and // fuUingtoni appear to be the
only Texas Humboldtiana without any traces of visi-
ble granulation.

It is my opinion that the taxonomic status of the
species under the genus Humboldtiana is debatable. It
is hoped that in the not too distant future careful
morphological studies of the soft parts will help to
clarify the taxonomic "picture".

Vol. 86 (2 - 4)

THE NAUTILUS

LITERATURE CITED

Pilsbry, H. A. 1927, "The Structure and Affinities of
Humboldtiana and related Helicid Genera of
Mexico and Texas", Proc. Acad. Nat. Sci, Phila.
79: 165-192.

Pilsbry, H. A. 1939, "Land Mollusca of North
America (North of Mexico)", 1, Part 1: 395-410.

Pratt, Lloyd 1971, "Humboldtiana agavophila, A
New Helminthoglyptid Land Snail from the Chisos
Mountains, Big Bend National Park", Southwest
Naturalist 15(4): 429-435.

Parodiz, Juan J. 1951, "Methods de conquiHo-
metria", Physis, Buenos Aires, No. 58, 20: 241-248.

Parodiz, Juan J. 1954, "A New Species of Hum-
boldtiana from Texas", The Nautilus 67: 107-108.

BOOK REVIEW

AUSTRALIAN SHELLS, illustrating and describing
600 species of marine gastropods found in Austra-
lian waters. By Barry R. Wilson and Keith Gillett,
with a preface by R. Tucker Abbott. 168 pp., 106
polychrome plates, 34 monochrome figures; page
size 9 by 11 'A inches. Charles E. Tut tie Co., Rut-
land, Vermont 05701, 1971. $21.50.

Biologist Barry Wilson and photographer Keith
Gillett have combined their talents to produce a pro-
fusely illustrated and informative handbook on the
shelled gastropods one would most likely encounter
by shore collecting and diving in Australian waters.
The introductory text includes brief discussions of
the classification, nomenclature and biology of mol-
lusks in general.

A plea is made for the conservation of Australian
mollusks, before irresponsible collecting reduces read-
ily accessible shores near populated areas "... to bar-
ren biological deserts . . ." In this regard, they cite
California as an example where "... some seaboard
schools and universities have to import specimens
from other areas or take their students to places
hundreds of miles away before they are able to look
at living animals instead of only seeing pictures of
them in books," a condition, unfortunately, not
hmited to our west coast.

For each family, a brief introduction including dis-
tributional, biological, and ecological data, is given,
together with a description of each species figured on
the full-page, color plates, which are conveniently
placed facing the text. Limitations of space have per-

mitted the inclusion of only 600 species; for example
of the 23 species of abalones living in Australian
waters, 12 are illustrated in the book. The descrip-
tions include data on size, range, and abundance, to-
gether with synonymous names that have been used
for Australian forms.

This book is outstanding for the numerous color
photographs and line drawings of living mollusks.
Hopefully, the inclusion of biological and ecological
data in this book will stimulate collectors to observe
and record such information, and to be more restric-
tive in the selection of specimens for their cabinets.
The authors suggest that only a few well-preserved
specimens of a species should be taken, and they rec-
ommend that females associated with eggs should be
left undisturbed.

There are few errors of commission for an under-
taking of this magnitude. Parts of the text are some-
what out of date. Some of the nomenclature is not
current. However, in most cases, the familial groups
requiring nomenclatural changes are undergoing in-
tense study by malacologists, and specialists have pro-
posed differing classifications, as in the case of the
family Muricidae.

This beautifully illustrated book is highly recom-
mended to anyone seeking information on the marine
life inhabiting AustraUan coastal waters.

William K. Emerson

Chairman and Curator

Departmen t of L iving Invertebrates

Tlie American Museum of Natural History

60

THE NAUTILUS

November 1972

Vol. 86 (2 - 4)

Fig. J. Photograph of Tom Iredale taken in September, 1938.

Vol. 86 (2 - 4)

THE NAUTILUS

TOM IREDALE (1880-1 972)

Winston F. Ponder and Gilbert P. Whitley

The Australian Museum
6-8 College St., Sydney, Australia

The name Tom Iredale will be familiar to most zo-
ologists and certainly to all malacologists and ornith-
ologists. Iredale was a remarkable man, for in his long
career he published over 360 papers and articles and
erected more than 2,600 new taxa. He worked not
only on molluscs and birds but also published papers
on mammals and fishes. Iredale has been called the
"Australian Linnaeus" - an apt title for a man of his
talents.

Iredale was born in Cumberland, England, on 24
March, 1880, and, when 21 years of age, sailed for
health reasons to Christchurch, New Zealand. He be-
came friends with W.R.B. Oliver, with whom he visit-
ed the Kermadec Islands in 1908. While on the
Kermadec Islands he made a life-long friend of Roy
Bell who collected large quantities of material for him
on Lord Howe and Norfolk Islands, in Victoria and
southern New South Wales. While in New Zealand he
published his first three papers in the Transactions of
the New Zealand Institute ( 1 907, 1 908).

Iredale left New Zealand in 1908 to return to
England, but on the way Charles Hedley persuaded
him to stay for the Australian Association for the Ad-
vancement of Science Congress in Brisbane. Thus in
February, 1909, Iredale had a first-hand experience
with Queensland molluscs by collecting at Caloundra
and also Port Curtis.

From 1909 Iredale spent much time in the British
Museum (Nat. Hist.) as a freelance worker, identify-
ing birds and molluscs. He worked with Mathews on
Birds of Australia and wrote several papers dealing
mainly with molluscan nomenclatural and bibli-
ographic problems. One of his finest efforts was his
critical commentary on Suter's Manual of the New
Zealand Mollusca, published in 1915. He also helped
Sherborn with his great Index Animalium and col-
laborated with C. D. O'Donoghue to produce a List

of British Nudibranchiate Mollusca, which was pub-
lished in 1923. He considered liis most spectacular
molluscan discovery to be Sherbornia mirabilis.

In April, 1920, H. E. Gregory, the Director of the
Bernice Paualii Bishop Museum at Honolulu, offered
Iredale a position on the Museum Staff, but this was
not accepted.

In 1923 Iredale came to Sydney for the Pan Paci-
fic Science Congress and went on a collecting trip to
Victoria with Pilsbry, who was also in Australia for
the Congress. Pilsbry, some years later, wrote to Ire-
dale (19th July, 1928):-

"Do you still ride on those market trains, such as
that we took from Port Pliillip? I have never really
Uked pigs since that ride in the society of so many
dead ones."

"I think it wonderful of you and Basset Hull to
dedicate your Chiton (excuse me! Loricate) book to
me. Of course I think you make the genera too small,
but this is a mere matter of opinion . . ."

Iredale was to cause a lot of controversy with his
philosophy on genera and species. After his arrival in
Australia in 1923, he pubUshed a paper based on Roy
Bell's collections from Twofold Bay, southern New
South Wales, in which he erected 1 1 1 new names.

After working v^th Hedley at the Australian
Museum, he was appointed to the position of Assist-
ant to Joyce Allan in the Conchology Department in
1924. In the same year he was appointed to the posi-
tion of Conchologist and was assisted by Joyce Allan,
with Phyllis Clarke engaged as artist. Hedley left the
Australian Museum in 1924 to become the Director
of the Great Barrier Reef Committee, a position
which he occupied for two years before his death. In
Iredale's early days at the museum two other
well-known conchologists, John Brazier and Thomas
Whitelegge, who had been retrenched during the de-

62

THE NAUTILUS

November 1972

Vol. 86(2-4)

pression of 1893, also visited the museum from time
to time.

Iredale's moUuscan work at the Australian Muse-
um was prolific and ranged from chitons to cuttle-
bones, marine borers to deepwater molluscs and land
shells.

Although Iredale was basically a museum worker,
he loved field work and considered this very im-
portant to gain a proper understanding of the animals
on which he was working. He made several collecting
trips to Queensland, including participating in the
Great Barrier Reef Expedition in 1928 and 1929, and
did much local collecting in New South Wales. He
visited Lord Howe Island in December and January,
1931-2.

A bibliography and an index to his new names was
provided in 1956 by McMichael and Whitley {Aus-
tralian Zoologist, 12(3): 211-250) and one of us
(G.P.W.) is currently revising this and preparing a
more detailed account of Iredale's life and work.

Many find Iredale's work difficult because of his
brief descriptions and seemingly casual introduction
of new names. These people have probably not seen
him at work using his unsurpassed knowledge of the
Hterature, tracing back to their beginnings any species
names under consideration. He never relied on pub-
lished synonymies, everything was checked and re-
checked with a book in one hand and a specimen in
the other. Hours of observation and research were
condensed, perhaps unfortunately, into a line or two.
He never used a typewriter, all of his work being
handwritten, including the finished manuscript. A
number of unfinished manuscripts and notes are pre-
sei^ved in the Australian Museum.

Iredale's philosophy on generic groupings changed
somewhat over the years. His classifications in eariier
papers, strongly abused by some conservative con-
temporaries, are now often adopted as "modern class-
ifications." In 1912 he wrote "I am convinced that all
future workers, to produce any lasting results, must
undertake monographic studies, and moreover, must

study series, note variation, also determine the sub-
species from such series, and discriminate between
species, subspecies and varieties. I foresee the time
when there will be more genera, fewer species and
more subspecies, with entire elimination of varieties."
What could be closer to the approach of the modern
taxonoirdst?

Unfortunately for Iredale, Australia has a vast
fauna with many perplexing and exciting unknowns.
Because of this, he was rarely able to live up to his
desired standards, although, with the help of Hull, he
produced excellent monographs of the Australian and
New Zealand "loricates" which were completed in
1927 and 1932, respectively. Several important mol-
luscan reference works were produced by Iredale, in-
cluding lists of the Australian, Lord Howe and Nor-
folk Islands and Papuan land molluscs, the freshwater
molluscs of Australia and the marine molluscs of New
South Wales (with D. F. McMichael). His nomencla-
tural and bibliographic contributions result mostly
from his period spent in the British Museum and after
his retirement in 1944, he produced a number of
bibliographic and historical accounts of Australian
conchologists.

Up until the time of his death, on 12 April, 1972,
at Curl Curl, a seaside suburb of Sydney, just after his
92nd birthday, Iredale was an Honorary Associate of
the Australian Museum and except for his last four
years, frequently worked in the museum. Many
genera and species of molluscs, birds, fishes, etc., have
been named after him, the last known to him was
Favartia (Miirexiella) iredalei Ponder, 1972.

Not only was Iredale's work extraordinary, but his
sharp wit, coupled with unusual dress and a broad
grin made him a personality few could forget. Perhaps
most of all he will be remembered by those who
knew him in Australia and elsewhere for his cheerful
help and assistance which was given generously and
willingly. Certainly many people will feel a deep per-
sonal loss at Tom Iredale's passing.

Vol. 86(2-4)

THE NAUTILUS

63

SHELL STRUCTURE IN SPIRULA SPIRULA (CEPHALOPODA)'
Ronald F. Thomas & Frasier 0. Bingham

University of Miami
Rosenstiel School of Marine and Atmospheric Science

Miami, Florida 33149

ABSTRACT

The external surface of the shell of Spirula exhibits laminar mesa-like projections
suggesting deposition over an extended period. No pores, through which transfer of ma-
terials could take place, were seen in the siphuncle at a magnification of 10,000X.

Tlie small cephalopod Spirula spirula (Linnaeus,
1758) is rarely seen alive althougli its internal shell is
commonly washed onto beaches in many parts of the
world. The animal inhabits depths of 200-1500 me-
ters (Voss, 1956) and is widely distributed (Bruun,
1943). The biology, function of the shell, vertical dis-
tribution and world-wide distribution, as known, have
been covered in detail by Bruun (1943). The shell of
S. spirula appears to be thin and fragile; however it
has been found to withstand pressures between 2000
and 3500 p.s.i. without being crushed (Denton &
Gilpin-Brown, 1971).

The ability of the animal to actively change the
contents of completed chambers has been dealt with
by several authors. Chun (1914) concluded that after
a chamber was completely formed, there was no
transfer of gases or liquids into or out of that cham-
ber. Bruun (1943) thought that gases could pass
through the siphuncle or shell. Denton &
Gilpin-Brown (1971) note that some chambers of the
shell contain hquids. It is their opinion that the ani-
mal is able to regulate the gas or liquid contents of
the chamber and thus employ the shell in buoyancy
control.

The surface structure of the shell and of the
siphuncle have not previously been described. A lack
of contrast and large sculpture on the shell surface
makes it difficult to see the surface detail with a liglit
microscope. The high resolution and depth of field of

* Contribution No. 1 564 from the University of
Miami, Rosenstiel School of Marine and Atmospheric
Science, Florida 33149

the scanning electron microscope made it possible to
observe the surface detail shown in this study. Pre-
sented here are scanning electron microscope photo-
graphs of the external sculpture of the shell of S.
spirula as well as the internal structure of the
siphuncle.

In large specimens of S. spirula the shell contains
about 35 chambers. The first chamber formed by the
animal (figures 1 & 2) is small, spherical and compara-
tively smooth. This chamber probably corresponds to
the unsculptured protoconch of other molluscs in
which shell growth after settling displays adult sculp-
ture characteristics. The first chamber is somewhat
separated from the remainder of the shell by a promi-
nent constriction (figure 2). The second chamber
(figure 2) exhibits traces of surface sculpture in the
form of minute ridges scattered over the exterior sur-
face. The sculpture on the second chamber is not so
well developed as that seen on following chambers.
Figures 3 & 4 show the ridges of the seventh cham-
ber. These ridges are unconnected, mesa-like pro-
jections of the shell surface and are laminar in struc-
ture (figure 4). The ridges are tall and distinctly
layered, indicating that their formation may involve
periodic deposition througli the lifetime of the ani-
mal. Appelloff (1893) found that the thickness of the
external surface of a newly formed chamber increases
during the addition of further chambers. The in-
creased thickness seen by AppellotT (1893) is indi-
cated by this study to be a consequence of periodic
deposition of thin layers of CaCo on the tops of the
mesa-like projections of the shell surface. In more re-
cently formed chambers such as the 32nd chamber
(figures 5 & 6), the ridges are not so well-formed as

64

THE NAUTILUS

November 1972

Vol. 86 (2 - 4)

those on the seventh chamber. They are set farther
apart and arranged in a linear pattern parallel and per-
pendicular to the axis of shell growth. The laminar
structure is still present although the ridges are not as
highly elevated as in the earher chambers. It appears
to us that ridges are formed near the region of new
shell growth and later additions of CaCo increase
their size and obscure their original Unear arrange-
ment.

The external surface of the siphuncle was scanned
at magnifications up to 10,000 X. The surface ap-
peared smooth and no pores which would permit ex-
change between materials in the chambers and in the
siphuncle were noted, but this does not exclude the
possibility that such pores exist and are too small to
show up at this magnification. The inner surface of
the siphuncle is quite rough (figures 7 & 8) and the
crystalline structure of the CaCo matrix is evident.

MAX

i^^^^^H^E^^^^^^^Hk^mE

•«> :'^

0

^^^^^^^^H§ mSSfr'*-

««^ate.

}sl^' j

\.'

H0b^^^'^

r^

■-•"'^^^''^Sfcs-*^

4i

/> ■ -/A

Vol. 86 (2 - 4)

THE NAUTILUS

65

Fig. 1. The first 14 chambers of the shell ofS. spirula.
20X. Fig. 2. The first and second chambers of the
shell. lOOX. Fig 3. The seventh chamber. Note the
numerous ridges that cover the entire surface. lOOX.
Fig. 4. A portion of figure 3, at higher magnification.
Note the laminar structure of the ridge. fOOOX. Fig.

5. The smaller and linearly arranged ridges of the
32nd chamber. SOX. Fig 6. Sculpture of the 32nd
chamber. 200X. Fig. 7. Calcium carbonate crystals in
the inner surface of the siphuncle. 2,000X. Fig. 8.
Laminated calcium carbonate crystals. 5,000X.

66

THE NAUTILUS

November 1972

Vol. 86(2-4)

ACKNOWLEDGMENTS

We wish to thank Dr. Donald Marszalek and Mr.
Wally Charm for their assistance and operation of the
scanning electron microscope. This work was sup-
ported in part by National Science Foundation grant
GB-24994X.

LITERATURE CITED

Appelloff, A. 1893. Die Schalen von Sepia, Spirula
und Nautilus . Kongl. Svenska Veten-
skaps-Akademiens Handl. 25: 1-106.

Bruun, A. 1943. The biology oi Spirula spirula (L.).

Dana Report No. 24: 1-46.
Chun, C. 1914. Die Cephalopoden. II. Teil. Myopsida,

Octopoda. Wissensch. Ergebn. Deutsch.

Tiefsee-Exp. "Valdivia" 1898-1899, 18: 405-552.
Denton, E. J. & J. B. Gilpin-Brown. 1971. Further

observations on the buoyancy of Spirula. Jour.

Marine Bio. Assoc. U. K. 51: 363-373.
Voss, G. L. 1956. A review of the cephalopods of the

Gulf of Mexico. Bull Marine Science 6: 85-178.

BOOK REVIEW

EDIBLE? INCREDIBLE! By Marjorie Furlong and
Virginia Fill. Faperback, 62 pp. (24 with full
color). Ellis Robinson Publ. Co. April 1972. $2.00.
Obtainable from Mr. Fom Rice, Box 33, Port
Gamble, Wa. 98364.

This is a charming and colorful guide to the com-
mon edible invertebrates and seaweeds of the Pacific
Northwest coast of North America. Clear colored
photographs, succinct descriptions, habitats, and
cooking hints are given not only for the plausible edi-

bles, such as clams, abalones and crabs, but also for
the incredible gourmet deliglits. such as sea urchins,
barnacles, sea cucumbers and chitons. Missing is a
warning that over 200 venturesome people in North
America have suddenly died of paralytic shellfish poi-
soning resulting from eating cooked mussels, clams
and periwinkles at certain seasons in certain areas, es-
pecially in northern California and both sides of
Canada.

R. Fucker Abbott
Delaware Museum of Natural History

Vol. 86 (2 - 4)

THE NAUTILUS

THE AMPHI-ATLANTIC DISTRIBUTION OF UlTORINA MELEAGRIS

Joseph Rosewater^ and Geerat J. Vermeij^

* Division of Mollusks, Smithsonian Inst., Wash., D. C. 20560
2 Dept. Zoology, Univ. of Maryland, College Park, Md. 20742

ABSTRACT

The gastropod Littorina meleagris (Potiez and Michaud, 1838), is now known to be
the second tropical species of Littorinidae found on both sides of the Atlantic. It has
recently appeared in Bermuda, and the new West African records may be the result of a
modern ship-borne introduction.

Littorina meleagris (Potiez and Michaud, 1838) is
a common western Atlantic littorinid gastropod living
in close association with algal mats at mid to high in-
tertidal levels (Lewis, 1960; Vermeij, in press a,b) (see
figs. 3, 4). Bequaert (1943) gave the geographic range
of the species as including southern Florida, the
Bahamas, the Greater and Lesser Antilles, and the
Caribbean coasts of Honduras and Colombia. Addi-
tional locahty records in the collections of the Na-
tional Museum of Natural History include Port
Aransas, Texas; Quintana Roo, Mexico; Portete,
Costa Rica (for locality see Houbrick, 1968); Devil's
Beach, Panama Canal Zone; Curacao; La Orchila Id.
(Rehder, 1962) and Catia la Mar, Venezuela; and
Barbados. It was recorded from Bermuda by Abbott
and Jensen (1967), who believed it to have been re-
cently introduced there (see map).

Wliile examining collections in 1968 at the Zoo-
logical Museum in Copenhagen, Rosewater noted the
presence of L. meleagris among tropical West African
material collected by the Atlantide Expedition in
1946 (Takoradi, Ghana) and by the Galathea Expe-
dition in 1950 (Teshi, Ghana). The specimens were
later borrowed for study through the courtesy of Dr.
J^^rgen Knudsen. The shells were all collected in dead
condition, many containing hermit crabs, and were
mixed with specimens of the morphologically similar
L. punctata (Gmelin, 1791) (figs. 1, 2, 5, 6.).

In July, 1971, Vermeij collected living specimens
of L. meleagris at Takoradi, in the western part of
Ghana. Most specimens were found in algal turf in the
low intertidal echinoid (Echinometra lucunter) zone
in association with Tricolia sp., Siphonaria pectinata
(Linnaeus, 1758), Fissurella nubecula (Linnaeus,
1758), and Patella safiana (Lamarck, 1819). Several
additional specimens were collected in permanent,
shallow, high intertidal pools, in which L. punctata,
L. cingulifera (Dunker, 1 845), and Merit a at rat a
GmeUn, 1791, were the dominant mollusks.

No other records are presently available for L.
meleagris from West Africa, neither Nickl^s (1950)
nor Buchanan (1954) mentioning it in their surveys
of the mollusks of Senegal and Ghana respectively.
The species could not be found in collections from
the 8 other localities visited by Vermeij in Ghana
during June and July, 1971, nor were specimens col-
lected by him in Senegal or Sierre Leone. The possi-
bility therefore arises that L. meleagris is a recently
introduced species in West Africa, especially since one
of the two localities from which it is known
(Takoradi) is a shipping port. The second locality

Map 1 . Distribution of Littorina meleagris (solid dots)
and L. scabra angulifera (open circles) in the east-
em and western Atlantic.

68

THE NAUTILUS

November 1972

Vol. 86 (2 - 4)

(Teshi) lies between Accra and the new shipping port
of Tema.

It is well-known that several boreal littorinids
(Littorina littorea, L. saxatilis and L. obtusata) occur
in both the eastern and western Atlantic. Up to now,
only one tropical species, the mangrove-associated L.
scabra angulifera (Lamarck, 1822), (see figs. 7, 8) was
known to be amphi-Atlantic in distribution (Rose-
water, 1970, pp. 455-458). The very restricted
known range of L. meleagris in West Africa and the
strictly tropical distribution of the species on both
sides of the Atlantic contrasts strongly with the signi-
ficantly greater latitudinal range of L. s. angulifera in
both the eastern and western Atlantic (see map, also
Bequaert, 1943; Nickles, 1950). Briggs (1967) and
Scheltema (1971) have noted that many amphi-Atlan-
tic fishes and mollusks, like the two amphi-Atlantic
tropical httorines, have a more restricted and often
more patchy distribution in the eastern Atlantic as
compared to the western Atlantic. This tendency may
be related partly to the much narrower latitudinal ex-
tent of tropical water (Ekman, 1953) and more vari-
able sea temperature regime in West Africa; as well as
to the pattern of east-flowing surface ocean currents
(Scheltema, 1971). In this connection, Lewis (1960)
has pointed out that L. meleagris produces floating
egg capsules which hatch into swimming veligers.

While L. meleagris was not included in a geo-
graphic distribution analysis of the rocky intertidal
mollusks at Takoradi (Vermeij, 1972), the habitat
characteristics of the species agree well with those of
other amphi-Atlantic species at that locality. In gener-
al, species not restricted to the eastern Atlantic were
found either to live cryptically beneath stones or in
other locally sheltered habitats, or to be eurytopic
with respect to shore level (Vermeij, 1972, in press,
a).

Differences between populations of L. meleagris in
the eastern and western Atlantic appear to be very lit-
tle greater than between adjacent western Atlantic
populations. Large numbers of specimens were not
available for analysis, especially from West Africa;
however, the following measurements are given (see
Table 1).

LITERATURE CITED

Abbott, R. T. and R. Jensen. 1967. Molluscan Faunal
Changes Around Bermuda. Science 155 (3763);
687-688.

Bequaert, J. C. 1943. The Genus Littorina in the
Western Atlantic. Johnsonia 1 (7): 1-27.

Briggs, J. C, 1967. Dispersal of Tropical Marine Shore
Animals: Coriolis Parameters or Competition? Na-
ture 216 (51 13): 350.

Buchanan, J. B. 1954. Marine Molluscs of the Gola
Coast, West Africa. Journal of the West African
Science Association 1 (1): 30-45.

Ekman, S. 1953. Zoogeography of the Sea. Sidgwick
and Jackson, Ltd., London, xiv + 417 pp.

Houbrick, J. R. 1968. A Survey of the Littoral Ma-
rine Mollusks of the Caribbean Coast of Costa
Rica. The Veliger 11 (1): 4-23.

Lewis, J. B. 1960. The Fauna of Rocky Shores of
Barbados, West Indies. Canadian Journal of Zoolo-
gy 38: 391-435.

Nickles, M. 1950. Mollusques Testaces Marins de la
C6te Occidentale d'Afrique. Manuels
Ouest-Africans 2 Paul Lechevalier, Editor, Paris, X
+ 269 pp.

Rehder, H. A. 1962. Contribucion al Conocimiento
de los Moluscos Marinos del Archipelago de los
Roques y La Orchila. Memoria de la Sociedad de
Ciencias Naturales La Salle 22 (62): 1 16-138.

TABLE L Comparative measurements of Caribbean and Takoradi, Ghana, colonies of Littorina meleagris.

Locality

Jupiter, Florida

Curacao

Santo Domingo

Takorad

No. of Specimens

6

12

8

6

Range of Lengths

3.8- 5.8

5.0-6.2

4.8-6.9

3.2 - 7.6

Range of Widths

2.6-3.5

3.0-3.9

3.0-4.3

2.2 - 4.3

Range Aperture Lei

igths

2.3-3.2

3.1 -3.9

3.3 - 4.3

2.1 -4.5

No. Whorls (often eroded)

3+

3+

5+

3+

Average: Width/Length

.61

.63

.61

.66

Average: Length

Length of Aperture

.57

.61

.65

.64

Vol. 86 (2 - 4)

THE NAUTJLUS

Rosewater, J. 1970. The Family Littorinidae in the
Indo Pacific. Part I. The Subfamily Littorininae.
IndoPacific Mollusca 2(11): 41 7-506.

Scheltema, R. S. 1971. Larval Dispersal as a Means of
Genetic Exchange Between Geographically Sepa-
rated Populations of Shallow-water Benthic Marine
Gastropods. Biological Bulletin 140: 284-322.

Vermeij, G. J. 1972. Endemism and Environment:
Some Shore Molluscs of the Tropical Atlantic. The
American Naturalist 106(947): 89-101.

Vermeij, G. J. In Press, a. West Indian Molluscan
Communities in the Rocky Intertidal Zone: A
Morphological Approach. In Smith, R. A. (Ed.),
Thomas F. Goreau Memorial Volume. University
of Miami Press.

Vermeij, G. J. In Press, b. Morphological Patterns in
High Intertidal Gastropods: An Essay on Adaptive
Strategies and Their Limitations. Marine Biology.

Fig. 1-4, Littorina meleagris. 1, 2 from Takoradi,
Ghana, USNM 707154, 6.4 mm. length. 3, 4 from
English Harbor, Antigua, USNM 423627b, 6.8 mm.

Fig. 5, 6, Littorina punctata, from Cotonou, Daho-
mey, USNM 707160, 10.5 mm. Fig 7, 8, Littorina
scabra angulifera, from Monrovia, Liberia, USNM
673999, 22.6 mm

70

THE NAUTILUS

November 1972

Vol. 86 (2 - 4)

TERATOLOGICAL LITTORINA SCABRA ANGULIFERA

Joseph Rosewater

Division of MoUusks
Smithsonian Institution
Washington, D. C. 20560

The occurrence of monstrosities in Littorinidae is
well-known, especially in the boreal species, Littorina
littorea (Linne), L. obtusata (Linne), and L. saxatilis
(Olivi) (Jeffreys, 1865, pp. 354-376; 1869, pi. 65; S.
V. Wood, 1848, pp. 118, 119, pi. 10, fig. 14, a-k;
Reeve, 1857, pi. 4, fig. 18a; Dautzenberg and Fischer,
1914, pi. 3; Bequaert, 1943, pi. 3, fig. 7.) Anomalies
of the shell apparently result either from injuries or
genetic aberrations and show up as sculptural defects,
changes in direction of coiling, or other obvious mal-
formations. Readily visible anomalies of the animal
consist of branching or other abnormalities of the
tentacles and penis, and many others have been noted
(Pelseneer, 1920). It seems probable that the con-
siderable frequency with which teratological Littorina
littorea was reported in Great Britain reflects the fact
that hundreds of tons of this species were collected
for food and that "pennywinkle" mongers were re-
sponsive to conchologists who paid well for unusual
specimens. A number of such specimens from Bil-
lingsgate Market, England, are present in the Jeffreys
Collection in the National Museum of Natural Histo-
ry-
Variation in shell morphology often is extremely
prevalent in some species of tropical Littorinidae (see
Rosewater, 1970, pi. 352). Anomalous individuals sel-
dom have been reported, however, and it is not
known whether this is because they occur with less
frequency in the tropics or simply have not been dis-
covered. An extremely turreted individual of Lit-
torina scabra angulifera (Lamarck, 1822) (figs. 1, 2)
was collected from Island SQ 1, near Squirrel Key,
Monroe County, Florida, by D. Simberloff, on June
19, 1969. A large population of the species was pre-
sent on Red Mangrove. Although the malformation is
extreme, when the specimen was first seen it was easi-
ly recognized as L. scabra angulifera. An inquiry was
made of the collector, through Dr. W. Heard, Florida
State University, Tallahassee, Florida, to determine
whether or not any other specimens exhibiting this
phenotype had been observed. The figured specimen
was the only one seen. A subsequent examination of
the collection of this species in the National Museum
of Natural History yielded one additional, smaller.

similarly malformed specimen, also from Florida, but
with no definite locality (figs. 3, 4). A perusal of the
reported and figured teratological specimens of Lit-
torinidae shows the turreted anomaly to be rather
common. The Squirrel Key specimen may be the re-
sult of a genetic defect since the turreted condition is
present in the earliest post-nuclear whorls of the shell,
the protoconch being missing. The "Florida" spec-
imen may have resulted from an injury because the
first 3-4 whorls appear normal and the turreted condi-
tion develops following an apparent disruption of
growth during the fourth revolution.

Figs. 1-6. Turreted and Normal Linoxm^ ■i.cd^ixdL'dngxx-
liferaf Lamarck, 1822).

Figs. 1, 2. Squirrel Key, Monroe Co., Florida (USNM
700046; 34.6x20.4 mm.).

Figs. 3, 4. ''Florida" (USNM 594251; 17.4 x 11.7
mm, ).

Figs. 5, 6. Normal specimen from mouth of Shark
River, Ponce de Leon Bay, southwest Florida ( USNM
129174; 36.9 X 20.1 mm,).

Vol. 86(2-4)

THE NAUTILUS

LITERATURE CITED

Bequaert, J. C. 1943. The Genus Littorina in the
Western Atlantic Ocean. Johnsonia 1(7): 1-27, 7
pis.

Dautzenberg, Ph. and H. Fischer. 1914. Etude sur le
Littorina obtusata et ses variations. Journal de
Conchyliologie 62: 87-128, 3 pis.

Jeffreys, J. G. 1865. British Conchology 3: 1-393-
1869./Zj/d 5, pL65.

BOOK REVIEW

THE GEOLOGY AND PALEONTOLOGY OF THE
MARINE PLIOCENE OF SAN DIEGO, CALI-
FORNIA (PALEONTOLOGY: PELECYPODA).

By Leo George Hertlein and U. S. Grant, IV. San
Diego Society of Natural History Memoir 2 (Part
2B), pp. 135-411, text figs. 7-13, pis. 27-57, paper-
back. July 21, 1972. $15.00 postpaid. Available
by mail from the San Diego Society of Natural
History, P. O. Box 1390, Balboa Park, San Diego,
California 92 11 2.

This quarto volume is literally a mine of informa-
tion on many families of marine pelecypods. The
taxonomic discussion includes 4 subclasses, 8 orders,
22 superfamilies, 39 famihes, 82 genera, and 144 spe-
cies and subspecies. Ten species are not positively
identified but are compared to known species, and
two additional ones are cited only to genus. Eleven
species, not seen by Hertlein and Grant but reported
by other authors, are included. The species with
small-sized shells are not neglected. One genus, one
subgenus, nine species, and four subspecies are
described as new. The new genus is Irusella (Vener-
idae), and the new subgenus is Axinola (Glycymerid-
idae). The new species and subspecies are: Nucula
(Ennucula) balboana, Mytilus (Crenomytilus) coaling-
ensis stembergi, Chlamys (Chlamys) hastata ellisi,
Chlamys (Argopecten) abietis abbotti, Lima (Limaria)
orcutti, Aligena diegoana, Bomia frankiana, Dosinia
ponderosa diegoana, Chione allisoni, Chione kanakof-
fi, Psephidia stephensae, Semele ashleyi, Thracia kana-
koffi.

The authors have made many taxonomic keys to
genera, subgenera, species, and subspecies. Four of
the seven text figures are drawings of pectinid genera
that show the exterior ornamentation of the valves.
Most of the photographs of the species are of good
quahty, and there are 348 of them.

Pelseneer, Paul. 1920. Les variations et Leur Heredite
chez les Mollusques. Brussels, pp. 1-826.

Reeve, L. A. 1857-1858. Conchologia Iconica 10, Lit-
torina, pis. 1-18.

Rosewater, J. 1970. The Family Littorinidae in the
Indo-Pacific, Part I. The subfamily Littorininae.
Indo-Pacific Mollusca, 2(1 1): 417-509, pis.
325-386.

Wood, Searles V. 1848. A Monograph of the Crag
Mollusca, Part I, Univalves, pp. xii -i- 1-208, 21 pis.

Most of the categories above the genus are like
those found in the Treatise on Invertebrate Pale-
ontology, and Hertlein and Grant cite the references
and refer to the first usages and spellings of these
higher categories. The type species of each genus and
subgenus is given with mode of designation. There is
additional information given on the genera and sub-
genera, such as geologic range, a brief description, and
sometimes geographic range and other species that
have been allocated to the genus besides the ones
found in the San Diego Formation. The descriptions
of the species are detailed and include the synonymy,
repository of type specimens, type locaHty, geologic
range, the original description, morphologic variabil-
ity, and a discussion of related species. The taxono-
mic descriptions comprise 200 pages.

References and supplementary data, which are
numbered consecutively within the text in parenthe-
ses, are listed after the descriptive taxonomic part of
the monograph. This portion of the volume comprises
37 pages, and there are 1,384 entries. It is in this sec-
tion that one finds information on the names of the
categories above the genus, and the type species of
many genera and subgenera that are related to those
described in the taxonomic discussion. Some addi-
tional information is given on ecology, geologic
ranges, and biology and geographic distribution of
genera, subgenera, and species.

Four pages are devoted to a list of collecting locali-
ties. The 23-page index is quite complete.

The most impressive thing about this monograph is
the incredible amount of scientific hterature that
Hertlein and Grant examined and cited. This work
will be useful to anyone doing research on marine
Pelecypoda, and it contains much good raw data for
the paleoecologist to analyze.

David Nicol

Box 14376, University Station

Gainesville, Florida 32601

72

THE NAUTILUS

November 1972

Vol. 86 (2 - 4)

TYPE LOCALITY OF UNIO PUMILVS LEA, 1838 (UNIONIDAE)

Samuel L. H. Fuller

Department of Limnology

Academy of Natural Sciences of Philadelphia

Philadelphia, Pa. 19103

ABSTRACT

A method for verifying the synonymies of Fusconaia masoni (Conrad 1834} and Lex-
ingtonia subplana (Conrad 1837) is discussed. The type locality of Unio pumilus Lea
1838 is corrected from the Neuse River system to the Cape Fear River system (both in
North Carolina). U. pumilus is a synonym of F. masoni, newly recorded from the Cape
Fear River.

The occurrence of a member of the primitive
unionid genus Fusconaia Simpson 1900 in the
Savannah River system was recorded by Fuller
(1971), who identified the species as maso^/ Conrad
1834, originally described as a Unio from the same
river system. Insofar as U. masoni appears to be the
earliest available name for this species, there is no
problem in accepting the combination F. masoni
(Conrad, 1834). This species should not be confused

with the conchologjcally very similar U. subplanus
Conrad 1837, the type species of the genus Lexing-
tonia Ortmann 1914. The distinctiveness oi subplana
has been verified on anatomical ground. Furthermore,
it is apparently limited to the upper James River (Ort-
mann, 1914).

It will be impossible to construct the correct
synonymies of Fusconaia masoni and Lexingtonia
subplana until their ranges are fully understood: the

Fig. 1. Known distribution of Fusconaia masoni (Conrad 1834) in the Cape Fear River
system of North Carolina, with the type locality of Vnio pumilus Lea 1838. Dotted lines
represent routes between Smithfield and Fayetteville available to Isaac Lea in 1827.

Vol. 86 (2 - 4)

THE NAUTILUS

type specimens of the several relevant taxa are devoid
of beak sculpture and soft parts, which are the only
discriminants between these two genera (Ortmann,
1914). Those taxa which were described from areas
where only one of these species proves to occur can
justifiably be assigned to synonymy; some of those
from areas where the two species prove sympatric
may have to be considered nomina dubia. In order to
apply such criteria, one must know the type localities
in question.

One of these taxa is Unio pumilus Lea, 1838,
whose type locality was cited by Johnson (1970:
301) as in the Neuse River system of North Carolina,
whereas the adjacent Cape Fear River system is cor-
rect. The point is of some importance because I have
Fusconaia masoni from the Cape Fear River: thus
Unio pumilus falls within that species' range.

In describing Unio pumilus, Isaac Lea (1838: 23)
wrote: "A single individual of this species was found
by me in 1827, in crossing the Black River, on the
road to Fayetteville from Smithfield." Contemporary
maps of North Carolina show that in 1808 there was
a single road connecting these towns and that a sec-
ond had been constructed by 1833 (Cumming, 1966:
pis. 9-10). The earher road crossed the Black River at
a point in the modern Harnett County about five
miles northeast of Erwin and about four miles
east-southeast of Coats (Fig. 1). The crossing of the
later route was about three miles southeast of Erwin,
some 1 0 river miles downstream of the original cross-
ing.

These points cannot be fixed with precision be-
cause modern roads do not necessarily follow their
original courses and because of the difficulty in
reconcihng early and modern cartography. Nonethe-
less, the type locality of Unio pumilus definitely is
somewhere between these two points as approximate-
ly defined. It is doubtless at or near the upstream
point because the later, more circuitous route (Fig. 1)
was less likely to be used in public transportation; be-
cause Cumming's (1966) post- 1833 maps do not
show this road (which suggests its relative unimport-
ance), and because Lea mentioned only "the" road
from Smithfield to Fayetteville.

On both early and modern maps is shown a Black
Creek in the Neuse River system, which flows sub-
parallel to Black River immediately to the southwest
of Smithfield. Lea had to cross both streams on his
1827 journey (Fig. 1). Their nominal similarity mis-
led Johnson (1970: 301), who thus amended the type

locality of Unio pumilus: "Black River [a tributary of
the Neuse River] on the road to Fayetteville from
Smithfield [=about 10 mi. W of Benson, Johnston
Co.] , North Carolina." The type locality is (about
five niiles) west of Benson, but this point is now in
Harnett County, and Black River is in the Cape Fear
River system.

This somewhat confusing situation is complicated
by the existence in this general area of another Black
River, also a tributary of the Cape Fear. This stream
is created by the confluence of Six Run and Great
Coharie Creeks, whose headwaters rise a few miles
south of Smithfield, but can be traversed on only the
most devious route to Fayetteville (Fig. 1). Moreover,
even Cumming's (1966) earlier maps clearly distin-
guish between this Black River and the streams "Six
Runs" and "Great Cohera" or "Big Cohary." Thus no
stream in this drainage could have been nominally or
geographically confused by Lea with the Black River
he crossed in 1827.

In view of all these considerations, it seems best to
restrict the type locality of Unio pumilus to: Black
River [Cape Fear River system: South River drain-
age] , on the road to Fayetteville from Smithfield
[=about 5 mi. NE Erv^n and about 4 mi. ESE Coats,
Harnett Co.] , North Carolina.

Thanks are due J. B. Post (Free Library, Philadel-
phia) and W. F. Caddell, Jr. (North Carolina State
Highway Commission) for aid in locating early and
modern maps of portions of North Carolina and to R.
T. Abbott for a critical reading of the manuscript.

LITERATURE CITED

Cumming, W. P. 1966. North Carolina in Maps. State
Department of Archives and History, Raleigli. Pp.
viii+ 1-36, pis. 1-15.

Fuller, S. L. H. 1971. A Brief Field Guide to the
Fresh-Water Mussels (Mollusca: Bivalvia: Union-
acea) of the Savannah River System. ASB Bulletin
18(4): 137-146, text figs. 1-14, 1 pL

Johnson, R. I. 1970. The Systematics and Zoogeo-
graphy of the Unionidae (Mollusca: Bivalvia) of
the Southern Atlantic Slope Region. Bulletin of
the Museum of Comparative Zoology 140(6):
263-450, tables 1-4, text figs. 1-5, pis. 1-22.

Lea, I. 1838. Descriptions of New Freshwater and
Land Shells. Transactions of the American Philo
sophical Society (N. S.), 6(1): 1-154, pis. 1-24.

Ortmann, A. E. 1914. Studies in Naiades [Part 3.].
The Nautilus 28 (3): 28-34.

74

THE NAUTILUS

November 1972

Vol. 86(2-4)

UNIO CAROLINIANA BOSC, 1801 (UNIONIDAE)

Samuel L. H. Fuller

Department of Limnology

Academy of Natural Sciences of Philadelphia
Philadelphia, Pennsylvania 19103

ABSTRACT

The date of authority for Unio caroliniana Bosc is established as 1801. Conflicting
interpretations of this taxon 's identity are reviewed. U, caroliniana should be considered a
nomen dubium.

Bosc (1801: 142, pi. 23, fig. 2) described and
figured Unio caroliniana in Volume 3 of the first edi-
tion of his Histoire Naturelle des Coquilles. This
volume is dated "An X," an abbreviation for the
tenth year of the French revolutionary (or republi-
can )calendar - i.e., the period from 23 September
1801 to 23 September 1802. The unsatisfactory
designation "1801/02" would have to be used as the
date of authority for Unio caroliniana had Dodge
(1952: 3>?>) not shown that Volume 3 of the
"Histoire" appeared no later than 23 October 1801.

Bosc (ibid.) compared his description and figure of
Unio caroliniana to figure 5 on plate 239 in the
so-called Encyclopedic Methodique of Lamarck and
collaborators. The figures in question resemble the
shell of a North American fresh-water mussel. Unio-
merus tetralasmus (Say 1831) (concept of Johnson,
1970: 339). Noticing the unclearness of Bosc's figure
(whose posterior hinge is particularly obscure). Lea
( 1852: 44) felt that it might as easily have been in-
tended {() represent the holarctic Margaritifera mar-
garitifera (Linnaeus 1758) (Margaritifcridae). This is
certainly possible because the nature of the lateral
tcclh m this figure might be considered to represent
those which may occur in younger A/, margaritifera
from Europe (Woodward, 1854) and North America
(Ortmann, 191<)).

On (he other hand, the type locality ofUnio caro-
liniana is "Ics caux dormanfcs (stagnant | en Caroline"
(Bosc, ibid.), whereas the range oi Margari I ij era mar-
garitifera HI the Atlantic drainage of the United States
extends no farther south than the upper Little
Schuylkill River drainage in northeastern Pennsyl-

vania (Ortmann, 1919: 3-5), and this species' depen-
dence upon pristine and flowing waters is
well-known. Moreover, the figures of Bosc and in the
Encyclopedic Methodique might be thouglit to
demonstrate the rougli periostracum, conspicuous
growth rests, postdorsal angulation, and somewhat
arcuate ventral margin of Uniomerus from larger
Carolinian rivers. Finally, Bosc (ibid.) redescribed M.
margaritifera (as Unio margaritifera) on the same
page where Unio caroliniana was described; one as-
sumes that he distinguished clearly between them.

For these reasons, one is tempted to grant Unio
caroliniana Bosc 1801 priority over Unio tetralasmus
Say 1831. Thus a perplexed Simpson (1900: 741,
1914: 711) did with a query include Unio caroliniana.
in his synonymy of Unio (Uniomerus) obesus Lea
1831. However, the figure of Unio caroliniana miglit
also illustrate Elliptio complanata (Liglitfoot 1 786), a
widespread species in the Atlantic drainage (see John-
son, 1970: 321), whose ready confusion with Unio-
merus is notorious.

Unfortunately, there seems to be no extant vouch-
er material which might help settle the matter. For
instance, E. Fischer (in correspondence) stated that a
type specimen of Unio caroliniana has not been locat-
ed in the National Museum of Natural History at
Paris, where the specimens figured by Bosc or in the
Encyclopedic Methodique are as likely to have been
deposited as at another institution, if any.

An ambiguous figure, an inadequate description
("Ovale, alongee; les sommets ronges. "), and the
probable loss of the figured type - these factors com-
bine to disguise the correct identity of Unio carotin-

Vol. 86(2-4)

THE NAUTILUS

75

iaim, which had best be considered a nonieii dubiuni.
In recent discussions of Uniomenis from the Atlantic
and Gulf drainages of the United States, Clench and
Turner (1956- 177-179) and Johnson (1970:
339-343) understandably ignored the name.

Confusion over the status of Unio caroliniana is
reflected in the curious evolution of its spelling and
citation in the literature:

Unio caroliniana [error for carolinianus] . Bosc,

1801: 142, pi. 23, fig. 2; 1824: 139, pi. 23, fig.

2; 1830: 139, pi. 34, fig. 2.

Margaron (Margaritana) Carolinianus Bosc [1801] ,
Lea. 1852: 44.

Unio carolinensis Bosc 1824, Simpson, 1900: 741;
1914: 711.
Fortunately, no one appears to have confused this
taxon with Unio caroliensis Pacome 1889, a syno-
nym of the European Unio crassus batavus Maton and
Rackett 1807 (Haas, 1969: 51)

Thanks are due R. T. Abbott for criticism of the
manuscript and for guidance among unfamiliar ele-
ments of the late 18th and early 19th century mol-
luscan literature.

LITERATURE CITED

Bosc, L. A. G. 1801. Histoire Naturelle des Coquilles

[First Edition], Volume 3: 1-292, plates. Deter-

ville (Paris).
Bosc, L. A. G. 1824. Histoire Naturelle des Coquilles

[Second Edition], Volume 3: 1-287, plates.

Verdiere (Paris).
Bosc, L. A„ G. 1830. Histoire Naturelle des Coquilles

[Third Edition], Volume 3: 1-287, plates. Raynal
(Paris).

Clench, W. J., and R. D. Turner. 1956. Freshwater
Mollusks of Alabama, Georgia, and Florida from
the Escambia to the Suwanee River. Bulletin of
the Florida State Museum 1(3): 97-239, pis. 1-9.

Dodge, H. 1952. A Historical Review of the Mollusks
of Linnaeus. Part 1. The Classes Loricata and Pele-
cypoda. Bulletin of the American Museum of
Natural History 100( 1): 1-264.

Haas, F. 1969. Superfamilia Unionacea. Das Tier-
reich, Lief. 88: x + 1-663.

Johnson, R. I. 1970. The Systematics and Zoogeo-
graphy of the Unionidae (MoUusca: Bivalvia) of
the Southern Atlantic Slope Region. Bulletin of
the Museum of Comparative Zoology 140(6):
263-450, tables 1-4, text figs. 105, pis. 1-22.

Lea, I. 1852. A Synopsis of the Family of Naiades
[Third Edition]. Blanchard and Lea (Phila-
delphia). Pp. xx -h 17-88.

Ortmann, A. E. 1919. A Monograph of the Naiades of
Pennsylvania. Part 3. Systemafic Account of the
Genera and Species. Memoirs of the Carnegie
Museum 8(1): 1-384, text figs. 1-34, pis. 1-21.

Simpson. C. T. 1900. Synopsis of the Naiades, or
Pearly Fresh-Water Mussels. Proceedings of the
United States National Museum 22(1205): viii -h
501-1044.pl. 18.

Simpson, C. T. 1914. A Descriptive Catalogue of the
Naiades, or Pearly Fresh-Water Mussels. Bryant
Walker (Detroit). Pp. xii + 1-1 540.

Woodward, S. P. 1 854. A Manual of the Mollusca,
Part 2: 159-330, text figs. 90-223, pis. 14-24. John
Weale (London).

76

THE NAUTILUS

November 1972

Vol. 86 (2 - 4)

GREATER ADAPTABILITY OF FRESHWATER MUSSELS
TO NATURAL RATHER THAN TO ARTIFICIAL DISPLACEMENT

Marc J. Imlay

Office of Endangered Species

Bureau of Sport Fisheries and Wildlife

Fish and Wildlife Service

Washington, D. C. 20240

ABSTRACT

Artificial displacement of freshwater mussels in the stream bottom (substrate
smothering, commercial harvesting, or removal and replacement ) was detrimental to mus-
sels more often than was natural displacement (natural sand formation, storm disturb-
ance, etc.). A biological explanation is presented that contributes to understanding why
water projects (dredging, channelization, impoundments, quarry washing) are so devas-
tating to freshwater mussels.

Freshwater mussels are artificially displaced in
their natural stream bottom environment in many
ways, including simple removal from the substrate,
being smothered by a substrate, and being disturbed
in their substrate during harvesting of a mussel bed.
The mussel may have the physical capacity to recover
from these events by digging back in or out, as the
case may be, re-orienting to the direction of current
flow, and regaining a desirable water depth and type
of substrate by migratory movement. But there is
some evidence that the mussel is more prone to ac-
complish these feats when the displacement is of
natural, rather than artificial, origin. Animal behavior-
ists are learning that organisms utilize their abilities to
surmount difficulties when certain response-triggering
mechanisms, much more probably associated with
naturally occurring problems, are present. To site one
example (Cloudsley-Thompson, 1961: 118), in reset-
ting daily activity patterns to a changing photo-peri-
od, the animal responds in accordance with its own
daily rhytiim of resetting sensitivity. Even bright light
or total darkness has no effect at other times of the
day.

SMOTIIl RING

Freshwater mussels presumably can extricate
themselves from a thin covering of sand or silt by em-
ploying the foot and valves (Barnes, 1955, 1962). It is
conceivable, however, that an unnatural covering oc-
curring at an atypical season wt)uld not trigger a
natural response mechanism for digging out, even
thougli the mussel has the physical means to do so.

The results of the following laboratory experiment on
mussel response to smothering as a form of artificial
displacement indicate that the latter possibility oc-
curs more often in practice. Mussels were placed on
their sides in large battery jars, covered with sand,
silt, or other substrates and provided with about one
foot of continuously aerated Lake Superior water at
16 C.

Detritus. - On July 6, 1967, nine A nodonta grandis
collected from a very slow-moving creek in one foot
of water were covered with three inches of detritus
consisting of leaf, twig, and other loose material from
the creek. A few mussels emerged each day until by
July 1 1 all the mussels had completely emerged.

However, sixteen Fusconaia flava were covered on
July 1 8 and in seven days two Fusconaia flava were
almost emerged, one half way up, but thirteen were
on the bottom (ten dead).

On July 14, eigiit Ligumia recta were covered 'Adth
the loose detritus and in four days three were at least
partly emerged but at least three were on the bottom.

Sand. - On July 14, seventeen Fusconaia Jlava were
covered with 7.5 inches of sand from the St. Croix
River. On July 18, nine A nodonta grandis were also
covered v^th the river sand. None of the Fusconaia
Jlava had emerged in four days. By seven days all the
Anodonta grandis were still at the bottom with six
dead.

However, muddy sand was collected from Upper
St. Croix Lake and the leaves and twigs sieved out.
This lake sand was much muckier than the river sand.
On July 14, nine Anodonta grandis were covered with

Vol. 86 (2 - 4)

THE NAUTILUS

77

the sand. By four days, eight Anodonta grandis were
emerged. On July 18, nine Ligiunia recta were cov-
ered by the lake sand. By seven days one was
emerged, three were two-thirds the way up (two
dead), and five were on the bottom (four dead).

Very fine, mucky sand, mixed with thick clay, was
obtained from St. Louis Bay in Duluth and 4.5 inches
of it placed July 19 on top of ten Lasmigona costata
and ten Lampsilis siliquoidea. By six days one
Lampsilis emerged in normal feeding position. With
four others the siphons broke surface and were active.
Another Lampsilis was almost emerged. One
Lampsilis was on the bottom but alive. Two others
were dead. Of the Lasmigona, nine were on the bot-
tom, seven alive and two dead. On July 25, ten
Lampsilis siliquoidea from Grand Lake, Minnesota
and eight Anodonta grandis were covered, along with
five Lasmigona costata and four Lampsilis of river ori-
gin. By six days two Anodonta grandis and two lake
Lampsilis siliquoidea were emerged, along with two
river Lampsilis, but five Anodonta grandis were on
the bottom alive and eiglit lake Lampsilis siliquoidea
were on the bottom (seven dead). The remaining two
river Lampsilis were both dead on the bottom along
with the five Lasmigona costata (one dead).

Silt. - On August 3, sand was obtained 50-100 feet

from the dam at Fish Lake outlet, Minnesota, and silt

300-400 feet from the dam. On August 5, under 7

inches of the silt, were placed twelve Anodonta
grandis and twelve under a duplicate silt test,

fourteen under 7 inches of the sand and thirteen
under a duplicate sand test. On August 14, in sand,
one was emerged and another was dead one inch
down. On August 24, no more had emerged in all
four tests. But in one sand test all eleven clams were
dead on the bottom and in the other sand test four-
teen were on the bottom dead. In one silt test, all
twelve were on the bottom dead and in the other silt
test ten were found on the bottom dead.

Grit. - Grit (material too coarse to be considered
sand) was obtained from the Spht Rock area of Lake
Superior and, on July 19, placed on top of thirteen
Fusconaia flava, four Amblema costata and
twenty-one Lampsilis siliquoidea.

On July 25, one Fusconaia flava and Lampsilis
siliquoidea were fully emerged, two Fusconaia flava
and one Lampsilis siliquoidea half emerged, four
Lampsilis with siphons emerged, one Amblema costa-
ta wath siphons emerged. Two Lampsilis and one Fus-
conaia flava had climbed four-fifths up the grit.

But, on the bottom there were nine Fusconaia
flava, three Amblema costata and ten Lampsilis
siliquoidea of which three were dead.

On July 25, sixteen Fusconaia flava and ten
Lampsilis siliquoidea from Grand Lake, Minnesota,
were covered with grit. By August 7, four Fusconaia
flava had emerged. By August 24, no more clams had
emerged, but about one inch from the bottom were
two dead Grand Lake Lampsilis. Two Fusconaia flava
were ahve, but on the bottom. The other ten Fus-
conaia flava and eight Grand Lake Lampsilis were
dead on the bottom.

Application. - The demonstrated failure of mussels
more often than not to climb out of smothering con-
ditions explains in part the devastating effect of
dredging (Van der Schalie, 1941: 308), channeUza-
tion, silt behind dams, and quarry washing (Stans-
bery, 1970), or for that matter, of dust storms and
surface run-off (Ellis, 1936).

Even Anodonta grandis was not immune to
smothering, yet Dennis (1971) notes "As the com-
mon name 'floater' impUes, this species is Hglit weight
with a thin shell, enabling it to survive in loose sand,
mud, and silt."

As an example of the difference to mussels be-
tween artificial and natural sand formation, Grier
(1922) may be quoted: "An old bed of 'niggerheads'
existing at Wild's Landing was found to be absolutely
covered with sand deflected by the dams . . . the best
collecting in this area was from the sand bars."
Scruggs (1960: 28) observed in impounded areas of
the Tennessee River recently plagued by 0.5-1.25
inches of silt cover that "a relatively large number of
dead shells, of different species and sizes, were found
under layers of silt one inch or deeper at several sta-
fions. These shells were embedded in a normal posi-
tion with the valves closed; the shells showed litfle
sign of erosion indicating that mortality had occurred
within recent months."

METHODS OF HARVEST

Grier (1926) considered the practice of harvesting
mussels with the shoulder rake a principal reason for
the decline of the clamming industry. Van der Schalie
(1941) has commented that there has been "an ex-
cessive amount of mussel-shell gathering with the use
of apparatus injurious to the mussel beds." He urges
(1948) enforcement against the illegal practices of
commercial hand-picking and forking because only
the acceptable method (with the crow-foot bar skim-

78

THE NAUTILUS

November 1972

Vol. 86(2-4)

ming above the surface and removing just the larger,
liiglier mussels) does not remove the young ones so
necessary in turn for replacement of the older stock.
Furthermore, "some of the larger specimens" im-
portant for reproduction are "down at least five or
six inches." ". . . completely beneath the surface of
the river bottom It is seriously doubted if the
crow-foot dredges used in commercial operations
would bring up specimens from such depth in the
mud and gravel" (Van Cleave, 1940).

Dennis (1971) explains the damage to mussel beds
by hand-picking or raking as a matter of removing too

many shells for restoring to be possible. I suggest that
an additional explanation may be that brailing either
removes a mussel entirely from the water or does not
disturb it at all, leaving the substrate below relatively
undisturbed. Forking and hand-picking, on the other
hand, with the kicking of the substrate, overturning

of rocks, raking the substrate, and throwing back
mussels too young for harvest may amount to artifi-
cial displacement of the mussels not collected.

REMOVAL FROM SUBSTRATE

Isely (I9I4) examined 164 "Quadrulae" in Okla-
homa for migration a year after artificial displace-
ment into Shootly Creek from the Chikaskia River.
He recovered 84.8 percent of the original tagged mus-
sels and showed little, if any, niigration. Yet these
very test mussels had been actively moving naturally
before collection as shown by track marks. Similarly,
46 percent of Anodonta gmndis were found in their
original location, isely did not report on whether the
mussels had burrowed in or not, let alone their orient-
ation relative to the direction of stream flow. Isely
placed some Quadrulae in one foot of water and they
migrated to deeper water.

On May 27, 1971 1 placed twenty large male
/.ampsilis ventricosa on their sides at one location in
three feet of water near the bank in the Eau Claire
River, Wisconsin. On July 1 1, nineteen of these mus-
sels were found in the same four by four foot place-
ment area (thus no migration). All wlmc burrowed in
except one mussel almost (m its side. All were orient-
ed posteriorly upstream ami fourteen essentially
parallel to the current flow.

Hi)vvcver, earlier, in the late autumn, I left about
fifty mussels (including Lampsilis vcntricosa) on their
sides in a four by four foot sandy area near the bank
of the I:au Claire River and three months later the
mussels were still on their sides except for two or

three which had burrowed in. There was no migration
from the placement area. Thus, artificial displacement
at an atypical season was too extreme for the animals
to adapt to it.

Stansbery (personal communication) also observed
that mussels collected in summer and left on their
sides in a pile for many weeks remained th^t way.

It may be speculated that certain species of mus-
sels establish a partial domicile by growing into a
shape which conforms to the particular microhabitat
pressures and requirements at the location of the
particular mussel. This follows the familiar experience
of finding arcuate and even odd-shaped specimens in
areas v^th boulders, stones, and small patches of suit-
able sandy substrate. Such an older mussel would be
less adaptable to displacement than a younger mussel.
It would appear that regulations for commercial clam-
mers to toss back undersized mussels or mussels that
are protected as endangered species may accomplish
little because the mussels in question have been artifi-
cially displaced and are not expected to necessarily
regain a viable posture in the substrate Bates (1971:
32) reported that hand-picked specimens fared better
in regards to simple mortality after three weeks of re-
placement in the streams, then did brail-collected
specimens but even they had eleven percent mortality
(450 specimens in test) in just three weeks.

An experiment showing exceptions to the rule
may also be described. On August 21, ten Lampsilis
siliquoidea from Grand Lake, Minnesota, were placed
on top of a substrate in a bucket in the laboratory.
This was their natural substrate collected from where
the clams were collected, just inside the perimeter of
the emergent vegetation zone in the lake. Running
water (at about 16 C) was made to flow in copious
quantity past the animals and by the next day eiglit
o\' the clams were in a normal feeding position. The
substrate felt hard, yet the clams had pushed their
way in.

Similarly, Trueman (1968) placed Margaritifera
margaritifcra in an aquarium containing sand from
the river they were collected from. The mussels gener-
ally burrowed in normal position after a day or so of
migrating around the aquarium.

On the other hand. Roscoe and Redelings (1964)
transplanted twenty-five specimens of Margaritifera
margaritifcra and some lay almost parallel to the bot-
tom, covered to much extent by stones. "Most of the
clams in the bed had the siphons directed upstream,
but among the transplants the clams assumed every

Vol. 86 (2 - 4)

THE NAUTILUS

79

angle from siphons directed toward the current to
siphons directed away from the current " Yet, in the
same river, these investigators observed whole beds
had been washed downstream by natural storms into
two new areas.

Tliat mussels are displaced naturally and adapt
well is attested to by the following field experiences:
A fruitful collection over a one-hundred yard stretch
on the Eau Claire River, Wisconsin, yielded several
species in large numbers but these species had been
collected out from that location two years earlier. It
is not known whether the repopulation came from
downstream or upstream, but it evidently represents a
natural displacement from somewhere else in the
strean^ These displaced mussels were not laying on
their sides or misoriented to the current, but ap-
peared to be in normal position in the substrate.
Furthermore, a similar experience (collecting out, re-
population, adaption to displacement) was encoun-
tered at another location on the Eau Claire River.

The type of distinction shown here between artifi-
cial and natural imposition on the mussels may be in-
volved in the unhappy circumstance that artificial
river-lakes such as the large impoundments on the
Tennessee River and elsewhere are so inimical to mus-
sels but natural river-lakes such as Lake Pepin, Minne-
sota, or Mussel Shoals, Alabama, supported even
more species and numbers of mussels than have large
rivers.

LITERATURE CITED

Barnes, G. E. 1955. The behavior of Anodonta
cygiiea L. and its neurophysiological basis. Jour.
Exp. Biol. 32:158-174.

Barnes, G. E. 1962. The behavior of unrestrained
Anodonta. Animal Behavior 10:174-176.

Bates, J. M. 1971. Ohio Mussel Fisheries Invesfiga-
tion, Final Report, Part 1, Center for Aquaric Bi-
ology, Department of Biology, Eastern Michigan
University, Ypsilanti, Michigan 48197.

Cloudsley-Thompson, J. L. 1961. Rhythmic activity
in animal physiology and behaviour. Academic
Press, New York. 236 p.

Dennis, S. D. 1971. Pennsylvania Mussel Studies.

Final Report, Center for Aquaric Biology, Eastern
Michigan University, Department of Biology,
Ypsilanri, Michigan 48197. 138 p.
Ellis, M. M. 1936. Erosion silt as a factor in aquatic

environments. Ecology 17:29-42.
Grier, N. M. 1922, Final report on the study and ap-
praisal of mussel resources in selected areas of the
Upper Mississippi River. Amer. Midland Naturalist
8:1-33.
Grier, N. M. 1926. Report on the study and appraisal
of mussel resources in selected areas of the Upper
Mississippi River, 1920-25. Amer. Midland Natu-
ralist 10:89-110.
Isely, F. B. 1914. Experimental study of the growth
and migration of freshwater mussels. Bureau of
Fisheries, Document 792. 27 p.
Roscoe, E. J., and S. Redelings. 1964. The ecology of
the freshwater pearl mussel Margaritifera margariti-
fera(L.). Sterkiana 16:19-32.
Scruggs, G, D. 1960. Status of freshwater mussel
stocks in the Tennessee River special scientific re-
port - Fisheries No. 370. U. S. Fish and Wildlife
Service, Washington, D.C. 41 p.
Stansbery, D. H. 1970. Rare and endangered fresh-
water mollusks of the Mississippi and St. Lawrence
River systems of North America. Malacologia
10:9-22.
Stansbery, D. H. 1971. Personal communication. Mu-
seum of Zoology, Ohio State University, Colum-
bus, Ohio.
Trueman, E. R. 1968. The locomotion of the fresh-
water chm Margaritifera margaritifera (Unionacea:
margaritanidae). Malacologia 6:401-410.
Van Cleave, H. J. 1 940. Ten years of observation on a
freshwater mussel population. Ecology
21:363-370.
Van der Schalie, H. 1941. Zoogeography of naiades in
the Grand and Muskegon Rivers of Michigan as re-
lated to glacial history. Papers of the Michigan
Academy of Science, Arts & Letters 26:297-310.
Van der Schalie, H. 1948. The commercially valuable
mussels of the Grand River in Michigan. Misc.
publ. 4 of Institute for Fisheries Research. Michi-
gan Department of Conservarion. 42 p.

80

THE NAUTILUS

November 1972

Vol. 86 (2 - 4)

A NEW SPECIES OY PERSICULA FROM

THE ARABIAN SEA (MARGINELLIDAE)

Barry Roth

1217 Waller Street, San Francisco, California 94 11 7

and Richard E. Petit

P. O. Box 133, N. Myrtle Beach, South Carolina 29582

Persicula masirana Roth and Petit, new species

Description of holotype: Shell of medium size for
the genus, solid, ovate, narrower anteriorly; surface
polished, unsculptured except for faint growth lines.
Color mottled yellowish tan with a broad, reddish
brown peripheral band and eleven narrow, spiral rows
of alternating white and brown spots. The first row of
spots placed immediately below the suture, the rows
on either margin of the peripheral band larger than
the rest, and the four rows on the band itself being
very small and fine. A narrow spiral row of white
spots occurs just anterior to the brown band, and
another just posterior to it. Spire not visible, im-
mersed in a pad of brown callus. Outer lip white,
arching above spire, terminating posteriorly in a wash
of white enamel which partly covers apical callus pad;
lip margin rounded, slightly thickened externally, its
anterior half having about 12 faint, oblong denticles a
short distance inside aperture. Aperture narrow,
widening anteriorly, white inside, with a curved sul-
cus at posterior end and a deep, oblique anterior ca-
nal. Parietal wall convex, covered with translucent,
white callus which thickens to a node in front of the
posterior sulcus. Columella with eight folds, including
one at base of columella; the two most anterior folds
strong, extending onto body whorl; remaining folds
much smaller, confined to aperture, becoming in-
creasingly faint posteriorly. Length 10.0 mm.; great-
est diameter 7.2 mm.

Holotype, no. 51327, Delaware Museum of Natur-
al History; type locality: Ras Jidufah (local name:
Monument Beach) at northeast tip of Masirah Island
(21°N, 59°E), in the Arabian Sea, off the coast of
the Sultanate of Muscat and Oman; collected by Sgt.
Eric Thompson, Royal Air Force, early February,
1971. The holotype was found in beach drift. Al-
though we have been able to examine only the holo-
type, notes from the collector indicate that it was not
the only specimen collected.

Discussion: With its pattern of spiral rows of spots
and single peripheral band, Persicula masirana differs
from all other species of the genus. It is most nearly

like Persicula catenata (Montagu, 1803) from Florida
and the Caribbean. The latter species averages 6 mm.
long; it has a tan shell, spiral rows of white sagittate
spots which are margined with brown lines on the
side nearest the outer lip. and three brown spiral
bands, each crossed by a single row of V-shaped dash-
es. Less similar are the Caribbean P. sagittata (Hinds,
1 844) and eastern Pacific P. phrygia (Sowerby,
1846), which lack brown banding entirely.

Among Indian Ocean species, Persicula pulchella
(Kiener, 1834), reported from Australia to the Per-
sian Gulf, has waved axial brown Hues on a white
ground.

The genus Persicula is an old one, with forms
much like some Recent species first appearing in the
Eocene. Persicula masirana and the similarly-pat-
terned Caribbean species may be isolated survivors of
a Tethyan stock which has undergone little modifica-
tion since the early Tertiary.

LITERATURE CITED

Hinds, R. B. 1844. Description of Marginellae collect-
ed during the voyage of H. M.S. Sulphur, and from
the collection of Mr. Cuming. Proc, Zool. Soc.
London 14: 72-77.

Kiener, L, C. 1 834. Species general et iconographie
des coquilles vivantes . . .: genre marginelle. Paris
(J.-B. Bailliere et fils). 30 p.

Montagu, G. 1803. Testacea Britanica or natural his-
tory of British shells, marine, land and fresh-water,
including the most minute: systematically ar-
ranged and embellished with figures. Romsey (J. S.
Hollis). xxxvii + 606 p.

Sowerby, G. B. 1846. Monograph of the genus Mor-
ginella. In: Thesaurus conchyliorum, or figures and
descripfions of shells. 1: 373-406,

Figs. 1, 2. Persicula masirana Roth & Petit, new spe-
cies. Dorsal and ventral views of holotype, length 10
mm

Vol. 86 (2 - 4)

THE NAUTILUS

QUATERNARY MOLLUSKS FROM FIJP

Horace G. Richards

Academy of Natural Sciences of Philadelphia
Philadelphia, Pa. 19103

In August. 1969, while visiting Viti Levu in the
Fiji Islands, I had the opportunity of maidng a small
collection of fossil mollusks in the Lautoka area. The
exact locality is:

Along a road which branches off the Wairambetia
Road, which branches off to the SSW from the
Natambua Road in northwest Viti Levu. This
locality is close to, or identical with, localities C
1 133 and RB 32 of the Fiji Geological Survey De-
partment and is about 0.5 mile NW of Pila Trig.
The elevation is slightly over 200 feet above sea
level.

The mollusks studied include specimens collected
by myself and my student-assistant, Richard Nelson
in 1969, augmented by material collected by Mr. Nel-
son in 1970, material supplied by Peter Rodda and
other members of the Fiji Geological Survey Depart-
ment, and specimens borrowed from the British Mu-
seum through the kindness of Dr. Patrick Nuttall.

Apparently two geological ages are represented by
the material studied. Specimens from sliglitly higher
elevations than the road are apparently Late Tertiary,
and are assigned to the Mba Group (Rodda, 1967),
following mapping by W. R. Dickinson. These spec-
imens have been transferred to Dr. Harry Ladd, of the
U. S. National Museum in Washington, D. C, who is
studying the Tertiary mollusks of Fiji. (Most of the
specimens loaned by the British Museum are appar-
ently of Tertiary age and v^l be studied by Dr.
Ladd.)

The material obtained from close to the road is ap-
parently of Quaternary age, since all species are
known to be living in the Fiji waters today. The fauna
is of special interest because it apparently marks the
highest elevation for Quaternary fossils on the island.
However this is not surprising in view of the tectonic
history of the Fiji Islands. Schofield (1971) records
high sea levels (Pleistocene ?) on the Lau Islands, up

^ Part of this study was made possible by a grant from
the Penrose Fund of the American Philosophical So-
ciety.

to elevation 770 feet on Tuvutha, and to 500 and 600
feet on other islands of the group. For data on the
geology of Fiji, see Ladd (1934), Bartholomew
(1959), Rodda (1967) and Schofield (1970). Th.
fauna here recorded is apparently considerably oldei
than the material mentioned by Schofield.

In addition to thanking Mr. Rodda, Mr. Nelson
and Dr. Nuttall for help in gathering this fauna, 1
want to express grafitude to Dr. Harry Ladd, of the
U. S. National Museum and Dr. R. Tucker Abbott, of
the Delaware Natural History Museum, and to an-
other student-assistant. Earl Shapiro, who assisted in
the study of the fossils at the Academy. Dr. John
Wells, of Cornell University, identified corals listed
below.

The following fossils have been identified from the
Quaternary portion of the locality:

Gastropoda: Trochus (Trochus) maculatus Linne,
Tectus (Rochia) niloticus (Linne), Turbo sp. (opercu-
lum), Nerita sp., Rhinoclavis (Rhinoclavis) aspera
(Linne), Clypeomorus sp., Epitonium sp., Cypraea
errones Gmelin, Cypraea sp., Naticarius marochiemis
(Gmelin), Polinices mammilla (Linne), Mitrella ligula
(Duclos) and Conus (Asprella) sulcatus Hwass.

Pelecypoda: Anadara scapha (Gmelin), Lithophaga
sp., Villorita sp., Chama sp., Gafarium dispar (Dill-
wyn), Tridacna maxima (Roding), Hippopus hip-
popus (Linne) and Spondylus ducalis Roding.

Corals (idenfified by Dr. Wells): Acropora sp.,
Stylophora pisstillata (Esper), Platygyra lamellina
(Ehrenberg) forma rustica (Dana), and Acanthocy-
athus grayi Milne Edwards and Haime. The first four
are reefs corals, while the last mentioned suggests a
water depth of at least 50 meters. In this connecfion,
it should be mentioned that H. Digliton Thomas
identified the coral Desmophyllum cf. crista-galli
Milne Edwards and Haime from this locality (32)
which "would suggest a Pleistocene rather than an
earher age for the deposit yielding it." (Bartholomew,
1959 p. 19).

LITERATURE CITED

Bartholomew, R. W. 1959. Geology of the Lautoka

Area, North-West Viti Levu. Geological Survey

Dept., Suva, Fiji, Bulletin 2, 25 pp.
Ladd, Harry S. and others. 1934. Geology of Vitilevu,

Fiji. Bull. Bishop Museum, Honolulu, no. 119:

1-263.
Rodda, Peter. 1967. Outline of the Geology of Viti

82

THE NAUTILUS

November 1972

Vol. 86(2-4)

Levu. New Zealand Jour. Geology and Geophysics
10(5): 1259-1273.
Schofield, J. C. 1970. Notes on Late Quaternary Sea
Levels, Fiji and Rarotonga. New Zealand Jour.
Geology and Geophysics 13(1): 199-206.

Schofield, J. C. 1971. Note on High Sea- Level Evi-
dence from Lau Islands, South-West Pacific. New
Z el and Jour. Geology and Geophysics 14(1):
240-241.

ON THE ALLEGED OCCURRENCE OF

LAMBIS VIOLACEA AND CLITHON

CORONATA IN INDONESIA

Henk K. Mienis

Dept. Zool., Hebrew Univ.. Jerusalem

In his prehminary account of the genus Lambis in
Indonesia, Butot (1955: 79, pi. 2, fig. 6) mentions
Lambis (Millepes) violacea (Swainson, 1821) for the
first and only time from an Indonesian locality:
Ambat, on the east coast of Madura. Quite under-
standably Abbott (1961: 167) was rather puzzled by
this record, as authentic material of this species is
only known from the islands in the western part of
the Indian Ocean. Yet he mentions Butot's locality in
his list of records, but omits it, however, from the
map, which shows the distribution oi Lambis violacea
(loc. cit: p. 168 and pi. 130).

The freshwater gastropod Clithon (Clithon) coro-
nata Leach, 1815, better known by its junior syno-
nym Clithon longispina (Recluz, 1841), is a fairly
common species of Mauritius, Reunion, Rodriguez
and Madagascar, all islands in the same part of the In-
dian Ocean. Van Bcnthem Jutting (1956: 283, fig.
12) mentions, however, Clithon coronata in her crit-
ical revision of the Javanese freshwater gastropods
from a locality in Indonesia: West Java, Muara
Tjibuni, Sukabumi. This record is reason for
Starmiihlner (1969: 56) to consider C coronata an
Indomalaysian stray into the freshwater fauna of
Madagascar.

During our current revision of the family Neritidae
in which we examined more than 120,000 specimens,

of which about a quarter had Indomalaysian locali-
ties, we never found a second specimen of C corona-
ta from a locality in Indonesia.

The similarity in both cases is therefore striking.
The link between both cases is however still much
closer. Butot's record of Lambis violacea from
Madura and van Benthem Jut ting's record oi Clithon
coronata from Java are both based on material in the
collection Ouwens, stored in the Zoological Museum
of Bogor, Indonesia. According to van Benthem Jut-
ting (1956: 283) it is a well-kriown fact that the late
Major P. A. Ouwens (1850-1922) was somewhat care-
less as to localities and labels. The possibility that
both records are based on wrongly labelled material is
thus very great. We propose, therefore, to leave both
records out of any further account until they have
been confirmed by more recently collected material.

On this basis Lambis violacea and Clithon coronata
have to be considered as species with a rather restrict-
ed range in the western part of the Indian Ocean,
with the possible center of their distribution being
Mauritius and the Cargados Carojos Shoals.

LITERATURE CITED

Abbott, R. Tucker, 1961. The genus Lambis in the
Indo-Pacific. Indo-Pac. Moll., 1(3): 147-174.

Benthem Jutting, W.S.S. van, 1956. Systematic
studies on the non-marine Mollusca of the
Indo-Australian Archipelago, V. Critical revision of
the Javanese Freshwater Gastropods. Treubia
23(2): 259-477.

Butot, L. J. M., 1955. Duivelsklauwen, boksbeugels,
schorpioenen of enterhaken. Penggemar Alam 35:
71-84, 3 pis.

Starmiihlner, F., 1969. Die Gastropoden der Madagas-
sischen Binnengewasser. Malacologia 8(1-2):
1-434.

Vol. 86 (2 - 4)

THE NAUTILUS

83

4NCISTR0LEPIS K A n AMURAI A NEW JAPANESE BUCCINIDAE

Tadashige Habe & Kiyoshi Ito

National Science Museum. Tokyo 160, Japan

We have had a good opportunity to obtain spec-
imens of a new Ancistroleph collected by the whelk
fishing boats of Mr. Shosan Mizutani at the Abashi-
ri-Yamatotai, off Abashiri (about 500 meters deep)
on the northeast coast of Hokkaido, through the
courtesy of Mr. Ryosuke Kawamura. a leading shell
collector in Japan.

These specimens closely resemble A. grammata
(Dalk 1907) and its varietal forms. A. g. hikitai
Kuroda, 1944, and A. g. yamazakii Kuroda, 1944, in
general features, but they have elongated shells with
rather weak spiral cords, except on the shoulder and
the base. Also, Ancistrolepis (Clinopegma) clamon
Dall, which seems to be a subspecies of Ancistrolepis
(ClinopegfJia) unica (Pilsbry, 1905), is a related spe-
cies in having an elongated shell, but has only one
proniinent shoulder cord down from the suture with
an obliquely-placed convex interval between them, in-
stead of the horizontally-placed, flat interval.

Therefore, they are new to science, and we are
pleased to name this interesting species in the honor
of Mr. Ryosuke Kawamura.

Ancistrolepis kawamurai new species
Figs. 1-3

Shell large, elongated and tabulated; rather thick
but fragile; 7-whorled white; covered with a
dark-brown periostracum, marked with finely, axially
lamellose growth Hnes and sculptured with the spiral
cords. Wliorl with proniinent T-rail-shaped, spiral
cords, two at the shoulder and 5 or 6 at the base of
the body whorl. Broad peripheral area between the
shoulder and the base smooth to spirally sculptured
in various degrees of strength. Space between the su-
ture and the shoulder spiral cord is canaliculated hori-
zontally and has a weak spiral cord on its bottom in
some specimens. Aperture roundly ovate, white with-
in. Outer margin gently curved but shouldered and
crenulated by the endings of spiral cords on the sur-
face. Canal rather wide, sinuated backward. Columel-
lar margin white, weakly curved and twisted at the
lower end.

Operculum rather thick, corneus, dark-brown,
ovate in shape. Nucleus situated at the narrowed low-
er end. Radula stenoglossate. Central tooth trans-
versely broad and has three cusps at the hind margin,
the middle one smaller than the other two. Marginal
tooth also has three cusps, the outer one the largest
and the middle one smaller than the inner one.

Heiglit 89.5 mm,. Breadth 42.4 mm. (Type spec-
imen presei"ved in the National Science Museum,
NSMT-Mo 41826) (fig. 1); height 87.4 mm., breadth
40.0 mm. (paratype specimen preserved in the
National Science Museum, NSMT-Mo 41827) (fig. 2);
heiglit 97.5 mm., breadth 48.2 mm. (paratype spec-
imen preserved in the Kawamura's collection); height
77.8 mm., breadth 41,6 mm., (paratype specimen
preserved in the Kawamura's collection); height 90,0
mm., breadth 40.0 mm, (the specimen examined for
its radula).

Type locality: Abashiri-Yamato-Tai (about 500 m.
deep), off Abashiri, Hokkaido in the Sea of Okliotsk.

Distribution: Besides the type locality, off the east
coast of Saghahen (46° 40'N., 143°58'E. 690 meters
deep) Collected by Mr. Kinji Takagawa.

Figs. 1, 2. Ancistrolepis kawamurai Habc & Ito, new
species. Fig. 1. Holotype, height 89.^^ nun.: Fig. 2.
Paratype, height 87.4 mm

84

THE NAUTILUS

November 1972

Vol. 86 (2 - 4)

LITERATURE CITED

Dall, W. H. 1925. Illustrations of unfigured types of

shells in the collection of the United States

National Museum. Proc. U. S. Natl. Mus. 66(17):

1-41, pis. 1-36.
Habe, T. & K. Ito 1965. Shells of the World in color,

vol. 1 (The Northern Pacific) 176 pp., 56 pis.
Habe, T. & K. Ito 1968. Buccinid species from Rausu,

Hokkaido. Venus, Jap. Jour. Malac. 27(1): 1-8, pi.

1.
Kuroda, T. 1931. On the Japanese species of the

chrysodonid whelks, Ancistrolepis and Japelion,

Venus 2(5): 221-234, text figs. 1-18.
Kuroda, T. 1944. New Shells from Japan (5), Venus

13(5-8): 237-239, text figs. 1-2.

Shikama, T. 1957. On some gastropoda from Nemuro
Strait, Eastern Hokkaido, Sci. Rep. Yokohama
Natl. Univ., (2)6: 31-36, pis. 10.

Fig. 3. Half a transverse row of the radula of Ancis-
trolepis kawamurai Habe & Ito, new species.

Vol. 86 (2-4)

THE NAUTILUS

85

AN UNDESCRIBED STRUCTURAL FEATURE IN THE MARSUPIUM

OF ELLIPTIO LANCEOLATA (LEA 1828) (UNIONIDAE)

Samuel L. H. Fuller

Department of Limnology

Academy of Natural Sciences of Philadelphia

Philadelpliia, Pa. 19103

ABSTRACT

Some populations of EUiptio lanceolata (Lea 1828) from the Atlantic drainage of the
United States bear a longitudinal rib on the posterior surface of each of a number of
interlamellar septa near the middle of the marsupial (outer female) demibranch. A dis-
cussion of the taxonomic implications of this discovery concludes with the rejection ofE.
arctata (Conrad 1834) as a possible name for such populations. The septal ribs of E.
lanceolata are contrasted to the structurally and evolutionarily very different ones found
in Uniomerus. Possibly the ribs in E. lanceolata developed as a source of additional sup-
port for the marsupium.

Samples oi EUiptio lanceolata (Lea 1828) from the
Cape Fear River, North Carolina, exhibit a curious
structural feature of the marsupial water tubes: a
more or less conspicuous rib runs medially along the
interlamellar septum for most of the height of the
(outer) demibranch. Although plainly visible from the
anterior side, the rib intrudes into the lumen of the
water tube from only the posterior surface of the sep-
tum (why the reverse should not be the case is ob-
scure). The rib is more common and strongly de-
veloped on septa which lie at or near the longitudinal
midpoint of the demibranch - i.e., in the region of its
greatest height. The rib interferes with formation of
the egg mass, which exhibits a corresponding, more or
less straight, shallow groove on its anterior surface.

These EUiptio are referrable to Unio perlatus Lea
1863, whose type locality is "Cape Fear River, Black
Rock Landing [=2 mi. S Kings Bluff, Bladen Co.] ,
North Carolina" (Johnson, 1970: 332). Most of my
material is from points upstream in Bladen and Cum-
berland Counties. Johnson (ibid.) referred this taxon
to EUiptio arctata (Conrad 1 834), originally described
from the Alabama River system in the Gulf drainage
and, in the Atlantic drainage, "known only from the
several type lots [of its synonyms] , and from a rather
large unlocalized series from the Cape Fear River,
North Carohna." An unusually thin and laterally
compressed shell with a somewhat arcuate ventral
margin is common to all this material - and does re-
semble the shell of Gulf drainage E. arctata - but
these characters frequently occur in E. lanceolata.

particularly in the southern one half or so of its
range.

That Johnson's (ibid.) concept of Atlantic drain-
age EUiptio arctata depends upon scattered specimens
without unique conchological characters suggests that
there is little to be gained by separating this material
from E. lanceolata. The septal ribs of Cape Fear River
lanceolata might be grounds for distinguishing them
taxonomically from other EUiptio had I not observed
(a less developed version of) this phenomenon in
conchologjcally ordinary lanceolata from the Patux-
ent River system on the Western Shore of Maryland
near the northern limit of this species' range. (It must
be emphasized that this point of view does not pre-
clude the possibility that true arctata occurs some-
where in the Atlantic drainage.)

Otherwise than septal ribs, Cape Fear River EUip-
tio lanceolata do not differ anatomically from the
descriptive notes of Ortmann (1912), Reardon
(1929), or Fuller (1971). Therefore, I am inclined to
view these ribs as nothing more than another (and oc-
casional) difference between this species and the
more common and widespread E. complanata (Light-
foot 1786), from whose ancestors the lanceo-
lata-type was probably an offshoot.

The single, longitudinal groove on the anterior
surface of the egg mass in some EUiptio lanceolata is
reminiscent of the numerous, transverse grooves on
both surfaces of the egg mass in Uniomerus. In the
latter genus, egg mass sculpture reflects imperfect sep-
tal fusion (Fuller, 1971), whereas the septum is a per-

86

THE NAUTILUS

November 1972

Vol. 86 (2-4)

fectly fused, surficially smooth structure in EUiptio.
The septal ribs of lanceolata, then, appear to be an
adaptation which has little or nothing to do with the
degree of development of the septum. Perhaps their
role is to provide the marsupium with additional sup-
port against its collapse and the destruction of its
contents. Perhaps these ribs developed during a pro-
longed arid period, when dessication was a threat to
life and reproduction.

Thanks are due G. M. Davis for a critical reading of
the manuscript.

LITERATURE CITED

Fuller. S. L. H. 1971. A Brief Field Guide to the
Fresh-Water Mussels (Mollusca: Bivalvia: Union-

acea) of the Savannah River System. ASB Bulletin
18(4): 137-146. text figures 1-14, 1 plate.

Johnson, R. I. 1970. The Systematics and Zoogeo-
graphy of the Unionidae (Mollusca: Bivalvia) of
the Southern Atlantic Slope Region. Bulletin of
the Museum of Comparative Zoology 140(6):
263-450, tables 1-4, text figures 1-5, plates 1-22.

Ortmann, A. E. 1912. Notes upon the Families and
Genera of the Naiades. Annals of the Carnegie
Museum 8(2): 222-365. text figures 1-28, plates
18-20.

Reardon, L. 1929. A Contribution to Our Knowledge
of the Anatomy of the Fresh-Water Mussels of the
District of Columbia. Proceedings of the United
States National Museum 75 (2782): 1-12, plates
1-5.

Vol. 86 (2-4)

THE NAUTILUS

87

AN UNUSUAL FORM OF LITTORINA UrWREA LINNE

FOUND IN NOVA SCOTIA

Derek S. Davis

Nova Scotia Museum

1 747 Summer Street

Halifax. Nova Scotia, Canada

During a survey ot^ tlie intertidal fauna of
Petpeswick Inlet, Halifax County, Nova Scotia, sam-
ples of Littorina littorea (Linne) were taken. On June
28, 1971, a rather unusual form was collected along
with normal L. littorea in a Spartina marsh at Petpes-
wick Harbour. This specimen and an example of the
normal form are shown in Figures 1 and 2. The popu-
lation density of L. littorea in this habitat was 1 20
per square metre, but only one specimen of the un-
usual form was found. It has a high spire, deeply in-
cised sutures and six whorls. Its shell length is 16.1
mm. and shell breadth 1 2.4 mm. The soft parts were
identical to those of normal forms. This specimen was
a female and did not contain trematode parasites.

The normal form (Fig. 2) was selected at random
from the specimens collected. Its shell length is 18.4
mm. and shell breadth 14.2 mm. There are six whorls.
This specimen was a male, parasitised by the digenetic
trematode, Cr}>ptocotyle lingua (Creplin).

Since marked variations in the form of L. littorea
are rather uncommon, the occurrence of this unusual
specimen is of interest. Jeffreys (1865) briefly de-
scribes four varieties and some other abnormalities in
L. littorea. Among these, var. turrita is described as
"spire turreted, the whorls being divided by a deep
and channelled suture". Jeffreys also mentions a
monstrosity with the spire much elongated. Without a
full description for reference it is difficult to know
whether the unusual form from Petpeswick is the
named variety or a mutant.

Read (1965 and 1966) has described shell-less
specimens of L. littorea from Maine, and suggested
that these may be mutants or victims of disease. The
unusual form from Petpeswick was examined for
larval trematode parasites, which sometimes cause
shell deformations in prosobranchs (Fretter and
Graham, 1962), but none were found.

Bequaert (1943) in his description of L. littorea
from the western Atlantic, states that the species
shows little variation on the coast of North America.
It may be that the varieties do occur more frequently
among the offspring, but that their survival would de-

pend upon the habitat in which they settled. The high
spire and small aperture would be a disadvantage on a
shore exposed to wave action, but not so in a salt
marsh. The sui-vival of the shell-less forms in the
eel-grass pond habitat has been attributed by Read
(loc. cit) to the low possibility of predation. L. lit-
torea are more commonly observed and sampled on
rocky shores and not in salt marshes, and so it is pos-
sible that unusual varieties have remained largely un-
detected.

The Petpeswick specimens described are now in
the collection of the Nova Scotia Museum under ac-
cession number 1 971 -Z- 180.

LITERATURE CITED

Bequaert, J. C. 1943. The genus Littorina in the west-
ern Atlantic. Johnsonia 1(7): 1-27.

Fretter, V. and A. Graliam 1962. British prosobranch
molluscs. London, Ray Society, 755 pp.

Jeffreys, J. G. 1865. British conchology, 3: 1-393.
London, van Voorst.

Read, K. R. H. 1965. Littorina littorea L., without
shell. Proc. Malac. Soc. Lond. 36: 307.

Read, K. R. H. 1966. Littorina littorea L., without
shells; a further note. Proc. Malac. Soc. London
37: 127.

» «3l^

1

Figs. 1 and 2. Littorina littorea from a salt marsh,
Petpeswick Harbour, Nova Scotia. L An unusual, tur-
reted form, length 16.1 mm. 2. A normal form,
length 18.4 mm (Photos by R. E. Merrick).

88

THE NAUTILUS

Vol. 86 (2-4)

NEWS

ICE TO SUBSCRIBERS

In order to have a new volume of The Nautilus be-
gin in January , rather than July, we have issued the
remainder of volume 86 in a combined issue of nos.
2, 3 and 4. Those who have been subscribing in ad-
vance on a calendar-year basis will continue to receive
their bills with the October issue. Those formerly sub-
scribing by volume will receive a bill in April 1973 for
only half a year. In effect, all subscribers will be re-
ceiving an extra half-year free-of-charge. By January
1974 all subscribers will be receiving the journal with
a beginning volume and a new year coinciding.

WESTERN SOCIETY OF MA LAC O LOG I ST S

The Sixth Annual Meeting of the Western Society
of Malacologjsts will be held at the Asilomar Confer-
ence Grounds in Pacific Grove, California, July 11-14,
1973, and will feature contributed papers, symposia,
displays and study workshops on molluscan subjects.

Inquiries may be sent to the Secretary, Mrs. Edith
Abbott, 1264 W. Cienega Ave., San Dimas, CA
91773. Applications for membership in the Society
should be sent to the Treasurer. Mr. Glenn Burgiiardt,
14453 Nassau Road, San Leandro, CA 94577. Dues
are $2.50 for regular members and $1.00 for stu-
dents.

Executive Board Members for the year are: Presi-
dent Mrs. Twila Bratcher; First Vice-President Dr.
James H. McLean; Second Vice-President Dr. James
Nybakken; Secretary Mrs. Edith Abbott; Treasurer
Mr. Glenn Burghardt; Members-at- Large Dr. George
Radwin and Dr. George Davis; the three most recent
Past Presidents are Dr. A. Myra Keen, Dr. Eugene V.
Coan and Mrs. Beatrice L. Burch.

AQUACULTURE JOURNAL

Aquacultiire is a new international journal devoted
to research on aquatic food resources related to hu-
man consumption. A specimen copy of vol. 1, no. 1
and subscription information ($26.30 per year) about
this quarterly may be obtained from the Elsevier Pub-
hshing Co., Journal Division, P. 0. Box 211, Amster-
dam - W. Netherlands.

WILMINGTON SHELL CLUB

The Wilmington Shell Club was founded on Octo-
ber 2, 1972. It meets the first Monday of the month,
October througli May, at 8:00 p.m. in the auditorium
of the Delaware Museum of Natural History. Officers
elected: President, R. Tucker Abbott; Vice-President.
C. John Finlay; Secretary-Treasurer. Sophie (Mrs.
Eldon) Homsey; Archivist, Russell H. Jensen; Coun-
cillors: Mrs. Edmond du Pont and Paul Leach. Annual
dues, $5.00 ($1.00 for each additional member of a
family); corresponding membership, $2.00.

R. E. PETIT SHELL BUSINESS

In order to devote more of his time to research
and other matters, Richard E. Petit of South Carolina
has sold his shell and book business to The Shell Cabi-
net, Box 29, Falls Church, Va. 22044, owned and
operated by the Misses Mary E. Young and Isabelle E.
Welch. The International Directory of Conchologists
will now be published by The Shell Cabinet.

IN SATISFACTION 01- POSTAL REGULATION 132-622:
OWNERS: Mrs. Horace B. Baker. Dr. R. Tucker Abbott,
Dr. Charles B. Wurtz. Printing: 1000 copies. Paid sub-
scribers: 596, sliipped by mail.

INFORMATION FOR SUBSCRIBERS

The annual subscription rate for The Nautilus is
$7.00 for individuals and $12.00 for institutions
(domestic or foreign). Subscriptions may begin either
in January or, preferably, in July when a new volume
begins. Send check or money order to "The Nautilus"
to Mrs. Horace B, Baker, Business Manager, 11
Chelten Road, Havertown, Pa. 19083.

Back issues from volume 72 to date are obtainable
from the Business Manager. Volumes 1 through 71 (if
available) may be obtained in reprint or original form
from Kraus Periodicals, Inc., 16 East 46th Street,
NewYork,N.Y. 10017.

Advertising rates may be obtained from the
Business Manager or Editor.

CONTRIBUTORS

Manuscripts: Authors are requested to follow the

recommendations of the Style Manual for Biological

Journals, which may be purchased from the American

Institute of Biological Sciences, 2000 "P" Street,

N.W. Washington, D.C. 20036. Manuscripts should be
typewritten and doublespaced; original and one copy

are required, to facilitate reviews. Tables, numbered

in arable, should be on separate pages, with the title

at the top. Legends to photographs should be typed

on separate sheets. Explanatory terms and symbols

within a drawing should be neatly printed, or they

may be pencilled in on a translucent overlay, so that

the printer may set them in 8 pt. type. There is a
charge of 50 cents per word for this extra service. All
authors or their institutions will be charged 50 cents
per line of tabular material and taxonomic keys. The
pubUshers reserve the right, seldom exercised, to
charge $32 per printed page.

An abstract should accompany each paper.

Reprints and covers are available at cost to
authors. When proof is returned to authors,
information about ordering reprints will be given.
They are obtained from the Economy Printing Co.,
Inc., R. D. 3, Box 169, Easton, Maryland 21601.

[ULY, 1972

THE

NAUTILUS

Vol. 86

No. 1

A quarterly

devoted to

malacology and

the interests of

conchologists

Founded 1889 by Henry A. Pilsbry. Continued by H. Burrington Baker.
Editors: R. Tucker Abbott and Charles B. Wurtz

-c

EDITORIAL COMMITTEE

CONSULTING EDITORS

Dr. Arthur H. Clarke, Jr.
Department of MoUusks
National Museum of Canada
Ottawa, Ontario, Canada K1A-0M8

Dr. William J. Clench
Curator Emeritus
Museum of Comparative Zoology
Cambridge, Mass. 02138

Dr. William K. Emerson

Department of Living Invertebrates

The American Museum of Natural History

New York, New York 1 0024

Mr. Morris K. Jacobson

Department of Living Invertebrates

The American Museum of Natural History

New York, New York 10024

Dr. Aurele La Rocque
Department of Geology
The Ohio State University
Columbus, Ohio 43210

Dr. James H. McLean

Los Angeles County Museum of Natural History
900 Exposition Boulevard
Los Angeles, CaUfornia 90007

Dr. Arthur S. Merrill
Biological Laboratory
National Marine Fisheries Service
Oxford, Maryland 21654

Dr. Donald R. Moore

Division of Marine Geology

School of Marine and Atmospheric Science

1 0 Rickenbacker Causeway

Miami, Florida 33149

Dr. Joseph Rosewater
Division of Mollusks
U. S. National Museum
Washington, D.C. 20560

Dr. G. Alan Solem

Department of Invertebrates
Field Museum of Natural History
Chicago, Illinois 60605

Dr. David H. Stansbery
Museum of Zoology
The Ohio State University
Columbus, Ohio 43210

Dr. Ruth D. Turner

Department of Mollusks
Museum of Comparative Zoology
Cambridge, Mass. 02138

Dr. Gilbert L. Voss
Division of Biology

School of Marine and Atmospheric Science
1 0 Rickenbacker Causeway
Miami, Florida 33149

EDITORS

Dr. R. Tucker Abbott

Delaware Museum of Natural History
Box 3937, Greenville, Delaware 19807

Dr. Charles B. Wurtz
3220 Penn Street
Philadelphia, Pennsylvania 19129

Mrs. Horace B. Baker

Business and Subscription Manager

1 1 Chelten Road

Havertown, Pennsylvania 19083

Second Class Postage paid at Wilmington, Delaware

MBl WHOI LIBRARY

lilH 17XV Z

I