Umvor
MAN UAL
J
ONCHOLOGY;
STRUCTURAL AND SYSTEMATIC.
WITTl ILLUSTRATIONS OF Till- si>K<
BY GEORGE W. TRYON, JR.
CONTINUATION BY
HENRY A. PILSBRY,
CoNSKKVATOK OK VHK CoXniouxiirAI. SECTION Ol THE Ni.TlTRAL SCIKNCKS «)K PlI I LADK1.1MI 1 A.
Vol. XIV.
POLYPLACOPHORA,
( Chitons. ) LEl'IDOl'LKURID.K, ISCHNOCH1TONID.K, CHITO> PAU1D
PHILADELPHIA : isluMl by Concholop-i<-<<l S<-
ACADEMY OF NATURAL SCI i
OF 1MIII.AD1 1 1MI1A 5
i-QMible check to the progress of Science is that the works on it arc becoming too voluminous; it is becoming scholastic : life will be too short to learn it, and no time will be left for discoveries.'
e told, whoever may be hurt by it. There is no doubt that some r* endeavor to conceal in a fog of mere words the want of clear and well-defined idea*, as well M of that critical knowledge which is indispensable in Natural Hi.--
this that has arisen that legion of phantoms which so effectually orieoced."— Anon. Gardener's C/imnitl,-. /)<•<-., 1854.
FREFA.CE.
The present volume contains a monograph of the importair extensive Order Polyplacophora, commonly known an Chiton*. Although represented by many species in all seas, tin Chitons have l>een much neglected by Conchologists. This may !><• due to the fact that their characters are not generally understood, or even seen in ordinary cabinet specimens; and again, no illustrated \\<>rk treat- ing the group scientifically has hitherto been produced. Certain it is, that if the serious study of this group be once begun, its at: tious will be found to equal or excel those of any other fain; The numberless modifications of form, the beautiful adapt structure to life-habits and station, the marvelous parallel develop- ments, producing almost identical structures in totally diverse phyla, — all distinguish the Polyplacophora as preeminently int< ing among mollusks.
The author begs those who may use this work to begin by taking apart one specimen of each species to be studied ; then find the genus by the Key on page xxviii. After a certain amount of practice the genus may be ascertained by removing valves vii and viii only ; but guessing it from the external features is in most cases uncertain and unscientific. As a rule, Chitons tell no secrets to those who will not take the trouble to disarticulate them.
It is hoped that describers of new species will hereafter state the generic characters of their novelties. It is as rational to describe a bivalve without examining its hinge-teeth, as to notice the outside only of a Chiton.
The synonymy is believed to be practically exhaustive, ex that useless references to mere lists giving no new information are omitted.
Attention should here be directed to the new theories of the origin of important structures of shell and girdle, given on pp. i\, \ii ; to the original system of classification (p. xxiii), and the phylogenies (pp. xxvii, xxviii).
The new species described herein which are credited to Car/ rest upon his types when the descriptions are g »» H* Mt. (as
in the case of Callochiton princeps, p. 50). In cases where I have
given original descriptions of new species, whether the specific names be Carpenter's or my own. the types are understood to be the ment described by me, in the collection of the Academy; wherever and whatever the original < mens may be. A case
in j...int is /> •// ocrtor, p. 60, and /. conspicuus, p. 63. It is
liy this expedient that confusion can be avoided in cases of real or fancied wrong identification, on my part, of Carpenter's .V . species.
Many new species not illustrated in the body of the work are figured from the typos in the Appendix. The Appendix should always be consulted when a species is not found elsewhere, as forms .M known generic position have been included therein.
e grateful task remains of acknowledging assistance from scientific friends and institutions. Through the intervention of DR. \\"M. H. DM. i.. Honorary Curator of the Department of Mollusks, U. S. National Museum, the writer has received from S. P. LAV-- . Secretary of the Smithsonian Institution, the drawings and .i/v prepared by the lamented PHILIP P. CARPENTER upon this group, a work of priceless value, embodying the results of many years study of the subject. Throughout the text of this volume will be foun fcfl from this MS.; such quotations in every case being
idly credited. For the loan of a large number of type spec- iim -us from the Smithsonian collections, the writer is indebted to the
nued kimlnesi of DR. DALL. To J. F. WHITEAVES of the
ula Geological Survey, PROF. WHITFIELD of the American
••urn of Natural Hi>tory, New York City, PROFESSOR F. W.
of Christchurch, New Zealand, and many other con-
chologists, the thanks of the author are due for specimens presented
or loaned.
H. A. P.
MANUAL OF CONCHOLOGY.
MONOGRAPH OF THE POLYPLACOPHORA.
Class AMPHINEURA.
Bilaterally symmetrical mollusks, the nervous system consist of four (two lateral and two ventral or pedal) parallel cords, me* in a cerebral ganglion ; other ganglia feebly or not developed. Anus posterior and median ; head without tentacles or eyes.
The Amphineura or Isopleura constitute one of the five primary divisions or Classes into which the Mollusk phylum divides ; and it is, in many respects, the most primitive of all. This class has been by most authors considered a sub-class or order of Gastropoda ; but the fact should be distinctly recognized that the characters com: to Gastropoda and ^Amphineura are either features possess* (hypothetical) primitive rnollusk, or are peculiarities evolved in response to similar habits of life. The Patellidce among Gastropoda have been repeatedly compared to the Amphineurous family Chitonidce; but the branchial cordon of Patell" is. .in no way homo- logous with the gills (or ctenidia) of Chiton, and the nervous and digestive systems are profoundly different.
The class Amphineura is divisible into two Orders :
Order I. POLYPLACOPHORA. Dorsal surface bearing eight in eating shelly plates ; head divided from the body ; gills numerous, occupying a lateral groove on each side between the foot and the encircling mantle ; foot adapted to creeping ; genital organs and nephridia paired ; sexes distinct ; radula well developed.
Order II. APLACOPHORA. Body subcylindrical or y.rmitorm, without shelly plates or valves; foot rudimentary or aborted, the mantle cavity being reduced to a ventral groove terminating in a posterior cloaca containing the rudimentary gills, and the outlets of anus and nephridia.
(v)
vi POLYPLACOPHORA.
ler POLYPLACOPHORA Blainville.
The further division of this order into families and genera will be found on page xxiv.
The following notes on the morphology of Chitons are mainly restri vaturea important from a phylogenetic or taxonomic
standpoint; the primary object of this work being, of course, the establishment of a natural system of the Order.
Tin. SHELL.
The shell in Chitons consists of eight imbricating pieces or valves, bound together by a leathery girdle of connective tissue. The valves, when freed of the girdle by soaking a few hours in water, are seen to be of three forms: the anterior, (or "head valve") semicircular in outline its apex elevated: the intermediate (sometimes called " central " or " median ") valves, squarish in shape, and the poste- •r " tail valve," which is like the intermediate valves with the addition of a sloping surface behind the apex or mucro. In struct- 'he wives are composed of two layer*, generally '/////V different in color and texture ; an ont'T AI»/»T, culled by Middendorff the tegmeu- tum, •///«/ <in inner, the articulamentum.
THE SURFACE or i m v M.VI.S (tenmentum) is divided in nearly all Chitons into clearly defined or indistinct areas. The interme- diate valves (fig. 1) are divided into lateral areas and a central area; the latter being subdivided into a dorsal or jugal tract, extending along the ridge of the valve, and two pleura or pleural tracts, occupying the side-slopes in front of the 'Hiirjonal line or rib. In some forms (fig. 2) the diagonal line is obliterated, the lateral areas and the pleural tracts being united into a single uniformly sculptured expanse, the Fig. l. Intermediate (four t h) /„/, ,-,,-y, /, , tr,,f area, on each side; the valve of h<kno,-kit*n L dorsal or jugal area remaining distinct.
2, 3, central area (subdivided int , • /•
1 juga, tract, and 2f 3| pleu. "!' -"on IS characterise of
tracts); 4, 5, lateral areas. «>ne -reat phylum of Chitons. Asa rule
Fig. 2. Intermediate valve oftne head-valve is sculptured all over Atm*tk9(hittt(if/HiWiii showing / like th« lateral areas. The posterior insertion plate, and Ue fig. 4) is divided into a central
*alnral Uni1 and a | .iiva : the former being
ar to the area so named in the intermediate valves
POLYPLACOPHOR \.
VII
and the latter corresponding clo>ely in .-rulptun- to the lateral areas'
In some genera the muero i> near or at \\\>
valve, and the posterior area is then reduced to a narrow
altogether absent (see pi. OL', li<j>. 17, I*;. In position, ti.
may be either anterior (pi. -^l liir. 1*3), or media,, < pi. 17, i
••i«r (pi. .VJ, figs. 22, I*:!) ; and it may be either elevat^l | fig. 9-J), or depressed (pi. 39, fig. 41), the last being sometime culled a Hat or planate mucro.
THE INNER LAYER OF Tin: VALVES (articulament i > i / 1 I- larger than the tegmentum, projecting in front in two lobes called sntural lamince, which are separated by a median bay, the j"ytl sinus. At
the sides of the intermediate va! and around the semicircle of the end valves, most Chitons have projecting plates called insertion plates, to whieh the girdle is attached. These are •*» commonly cut into teeth by transverse slits. From the slits to the apex of each valve inside, run slight grooves and rows of pores, known as slit-rays; often they are obliterated, but in forms having a highly developed system of sense-organs in the tegmentum, the
Figs. 3, 4. "intermediate and PareS °f the ^W* 9Q rve &S D6rve
posterior valves of Ischnochiton foramina. The teeth are sometimes conspicuus. finely cut or crenulated, (technically
" pectinated ") between the slits ; and in some forms the edges of the teeth are thickened outside, or " propped." Fig. 3 represents the interior of the fourth valve of an Ischnochiton, showing the slits, teeth, insertion plates, etc.
The tegmentum is essentially cuticular in nature. It consi>' a chitinous foundation substance, impregnated with salts of lime. It is perforated at the surface by a multitude of minute, definitely arranged pores of two sizes, called by Moseley, the larger //<"/<*/"/ the smaller micropores (see pi. 52, fig. 28, showing two megalopores and many micropores). Each megalopore leads into a cylindrical chamber which is continued below into a wide canal, ffhich as it penetrates deeper toward the plane of junction of tegmentum and articulamentum, curves outward toward the girdle-margin of the former. On reaching the plane of junction it joins a plexus of
viii POLYPLACOPHOBA,
main canals which ramify horizontally in this plane, and find open- ing from tin- valves at the eaves, or outer bases of the teeth and anterior sinus. From the sides of the megalopore chambers or from the deeper plexus of canals, are given off fine canals which perforate •••irmmtu: illy and join the bases of the micropore cavities.
All of these canals are occupied by fibrous and nerve tissues con- tinued in from the girdle and interior. From these ramifications are given off l»rum -lies to each megalopore canal, in the superficial chamber of which they expand into obconic knobs of highly refract- ing tissue, sensory in function, and in all probability tactile. These knobs are calk-d l>v Moseley, megahesthetes ; they are capable of being somewhat i'1-otnidi d t'nmi the mouths of the pores. The micro- pores hold exactly -imilar but smaller sense-organs, the micr (Esthetes. These structures are found in probably all Chitons ; but in certain genera they are subobsolete. In others some of the megalaestlietes have become transformed into eyes. These are connected with the network of soft tissues, and occupy pear-shaped cavities like the true megabesthetes. On one side the bulb of the pear, more or less near its extremity, is closely applied to the outer surface of the tegmentum, and here it-; wall is pierced by a circular aperture, the pupil-like opening. This opening covered by the cornea, the periphery of which extends to a considerable distance beyond its margin all round.
6 cornea is a concavo-convex, watch glass-shaped lamina, trans- parent, and calcareous in structure, being continuous all around with the superficial calcareous layer of the tegmentum. "The pear- shaped cavity of the eye in the tegmentum is lined by a dark brown pigni mbraiM- of a stiff and apparently somewhat chitinous
texture, which forms the eye capsule. This capsular membrane exactly follows the shape of the eye cavity, except near the surface of the tegmentum, where its margin curves inward beneath the 'rming a sort of iris and bounding the circular pupil,
h is of less diameter than the cornea. The ;ip2rtureof the pupil is occupied by the front surface of the lens. The lens is perfectly
parent and ! :md strongly biconvex. It is filled in
behind the iris aperture. It is composed of soft tissue and dissolves in strong acetic acid gradually and completely, showing a fibrous dis-
atructure in the process. There is a space between the front surface of the lens and the cornea.
' Within the pigm. nt« d tubular prolongation of the eye capsule
POLYPLACOPHORA.
the numerous fine fibres composing the optic nenre beoome lepai
from one another and loose. Immediately im<I.--nM-;itli tlif n-tm:i tin- fibres become still more widely separated, forming :m expansion of fibres. The retina is formed on the type of tliat of If, //./-, mid net. as might have been expected, on that of the dorsal eyes of Onr Ind- ium or the eyes of Pecten. The fibres of the optic nerve do not pass in front of the layer of rods to be distributed to them from in front, but are directed to the rods directly from behind. The retina pre- sents a single layer of short but extremely well defined rods, the extremities of which are directed toward the light. The rods when viewed from the surface of the layer they compose are seen to be hexagonal or pentagonal in .outline, and each contains a nucleus. They form a layer which is concave toward the lens, there being a space between the hind surface of the lens and the concave face of the layer."
Two eyes from the shell of Enoplochiton (x 40) are shown on pi. 52, fig. 27. On pi. 51, fig. 3 is seen an eye of Schizochiton magnified 200 diameters, showing outside the pigmented eye-capsule, seen partly through the superficial layers of the tegmentum, inside of which is the cornea, and the lens, seen through the cornea.
The arrangement of the eyes varies in different genera, as will be seen by reference to the systematic descriptions. Eyes are present in but one family of Chitons, the Chitonidce; and in this group they are found in all but two genera. In these two the megalsesthetes are larger and more regularly developed than in any Chitons of other families. This high development of sense organs is associated with the most complex system of insertion-plates, the completest form of girdle-armor and of gills to be found in the Polyplacophora. The family Chitonidce therefore, easily ranks as the consummation of Chiton development. Tonicia or Acanthopleura represent the utmost height yet attained by the great Amphineurous branch of molliisk life.
Theory of the origin of valve-structures. Any rational theory of the development of a structure must rest upon a knowledge of the rela- tions of that structure to the organism possessing it and to the external world. In discussing the genesis of the insertion-plates of Chitons we must therefore bear in mind (1) that the function of these plates is to bind the valves firmly to the girdle, and (2) that the entire force of all impacts on the valves is transmitted to plates, which are separated from the solid surface supporting the
X POLYPLACOPHORA.
:il Ity a thin pad of girdle. It is to the direct effect of impacts and - ntinnally l>rought to boar upon the growing edges of
these plates, that their development is duo, in precisely the same manner that the enlarged joints of a laborer's hand are the result of
:m pacts and strains to which they have been subjected. All Chitons which live in situations exposed to the buffeting of the surf, possess highly-developed in>ert ion-plates, which are, moreover, in nearly every cases. : >u<ly corrugated for the more effective
grasp of the girdle. Examples are the groups Enoplochiton and
tomura on the west coast of South America, Acanthopleura in the West In. li<-> and el-ewhere, JJn/ojiluira in Australia and Japan, all rmiarkable.forthe great development of strong, rough insertion plates, and equally for the very exposed situations in which they live, »t'ten subjected in the full force of the surf. It is, of course, the belief of the writer that characters acquired by the action of natural forces, acting upon many generations, become hereditary ; but in tural selection " no doubt has had a certain consider- able effect, although the process has, I believe, been mainly one of selection from definite variations produced by the mechanical causes described above, not selection from indefinite variations in all direc- tions.
On the other hand, forms living in less exposed stations, such as
ath stones at or below low water, have thin, smooth insertion plates (IMfioeAifoft) etc) ; and at great depths, where the motion of the water and its power of transporting pebbles or stones is reduced to a minimum, and where therefore the valves of the Chitons are not
• t to impacts or strains from without, the species are found to be entirely without insertion plates. This excessively weak organ iza- tion has been transmitted unchanged from the Paleozoic Chitons, all of which lacked insertion-plates; and it is a significant fact that [Ofl typ,- lias been able to exist to the present time only in deep water, where the forces which I believe to have moulded the modern Chitons do not act, and where competition in the life-struggle is less severe than in the shallows.
In this connection the case of J't'U-l/Jwra (PlacojiJinroj,*!*) ntlnn- tica shoul i Thi> species was dredged off New England in
•ni\\n tins., — depths beyond the limit of the penetration of li-ht, and of course far beyond the reach of appreciable water movement,
r l>y currents or surface disturbances. The conditions therefore demand no stronger apparatus for the attachment of the valves to
POLYPLAOOPHO1 XI
the girdle than is possessed l>y Lepidopkurui ; ami in fart \\o find that its insertion plates are reduced to very >hort Mmm anterior " teeth " arc small, low, unevenly notched, and not n« as long as the overhanging eaves. It is only n<-r. that the genus Ptaxipkora, tin- nearest ally of I'/m-ojJi" remarkable for the length of its strong, regularly slit insertion plates. The same is true of the entire family Mnjmli'n^r, to whieh these genera belong. In Pln<'ophorop«i* u/A/.//.//m wo have, there- fore, a member of a family of littoral Chitons, which by descent into the abyssal region has partially lost by retrogressive development through disuse the characters originally evolved to fit the ancestral forms for existence in the littoral zone. Further deep sea researches will probably reveal other cases of degeneration along the lines here indicated ; and it is not impossible that forms as destitute of insertion plates as the genus Lftpidopleurus have been produced from hi. types by retrogessive evolution ; but there is at present no evidence of the existence of such forms.
THE GIRDLE.
This organ variously called ligament, zone, or girdle, is a baud of connective and muscular tissues extending around the valves, the edges of which are imbedded in it. The surface of the girdle is variously clothed with scales, spines, haiis or spicules, or is naked. The armor, whether of spines, scales or hairs, consists of a chiti- nous foundation more or less infiltrated with lime. The girdle- appendages vary greatly in development among closely allied species; but the general type of covering is a moderately constant generic character. In some forms the girdle encroaches upon or entirely covers the valves. In some genera having a posterior sinus in the tail-valve, the girdle has a corresponding sinus or slit ; in others it has no sinus, but in life is always curved upward into a posterior conduit, serving for an outlet for the anus and gills.
In some forms having hairy or spiculose girdles, the hairs or spicules are gathered into tufts or groups at the sutures (i. e. lateral points of junction between valves), and around the anterior valve ; issuing from pits or pores at those places (see pi. 5, fig. 97). In their incipient stage, these sutural tufts are merely the gathering together of two or several of the ordinary surface hairs: in their full development they are dense clusters of long spicules ; and in their decadence only a small pit or pore remains. The presence of
Xll POLYPLACOPHOR \ .
pores or tufo has been considered by systematists a character of great value; but not with justice. The fact is that at least three
H in the development of Chitons has this feature appeared
independently ; first in the genus Hemiarthrum of Lepidopleuridce,
form having a pore at each suture, and six around the head
valve; second in Call; / (culminating in Mopaliidci) where
pores are excessively inconstant, and the number around the head valve indefinite (0-6) ; and for the third time in Acantho"
"he and its derivative l'nj/>foplacid<je, where the number of tufts around the head valve is invariably four, in genera having pores. Every genus (if it has more than one or two species) con- taining pore-bearing species, includes also forms in which the pores or tufts have become subobsolete or entirely lost. In the genera of Mopaliirla, the pores are occasionally not of specific importance ; and the same is true of Amu-nl<i.
• gene*i* of *,</,//•<// tufts is not beyond the reach of theory. I believe them to be the direct result of over-nutrition of the girdle at the sutures, caused by its greater mobility at those points. It is »us that every motion of the valves must cause a flexure of the girdle at the sutures; this brings a greater flow of nutriment to the •timulated portion, in this case a narrow strip, resulting in a more exuberant growth there.
HEAD, FOOT, GILLS, ETC.
Viewed ventrally Chiton presents a fleshy foot, similar to that the Gastropoda (pi. 34, fig. 68). Separated from this by a sinus is the ht-ad. with the mouth in the center of the disk, which is gen- erally surrounded in front by a lappet called by Carpenter the There are no tentacles or eyes. The inner edge of the ventral surface of the girdle may be regarded as the mantle. It is sometimes fringed or produced into finger-shaped processes in front. The gills consist of a row of triangular branchial plumes extending near the tail forward from a fourth to the entire length of the The anus is median and posterior, generally opening on * Pal)illa - nephridial openings are in the gill-groove, at the
:iml in front of the anus. The two genital openings are in front of the nephridial orifices.
radula has been investigated by Loven, Sars, and especially ill, who describes the teeth as follows : " In all Chitons exam- ined there is a simply cuspid rhachidian tooth, and on each side a
POLYPLACOPHORA. XI II
translucent minor lateral of varying form ; :i major lateral la- than any of the other teeth, with a conspicuous black cusp, which may have from one to four denticles ; two boss-like or thick' uncinal plates of irregular shape ; a twisted spatulate uncinal, and three scale-like or slightly thickened external uncini. With the exception of the spatulate uncinus (which is aborted in a very few species) none of the uncini are much raised above the plane of the odontophore, and none present any characters of importance. '
Dall has figured and described the dentition of species belonging to over half of the genera and subgenera recognized by Carpenter including all of the main types. He concludes that as yet no char- acters affording grounds for even generic distinctions can be found in the teeth, which exhibit a most surprising uniformity throughout the entire group. The dentition of a number of genera not exam- ined by Dr. Dall has been worked out by the writer, but without result as far as the discovery of structures of taxonomic value is concerned. It is evident that while some minor features of the dentition are characteristic of groups founded upon other charac- ters, we need expect little assistance in larger questions of group affinities from the further investigation of this organ.
The gills are "posterior" or short in the lower Chitons, the Lepidopleuridce, and also in the lowest Ischnochitonidce, and in most genera of the phylum Acanthochitidce—Cryptoplacidce, which arose from an early Ischnoid stock. All other Chitons, including the higher Ischnochitonidce, the Mopaliidce and the Chitonidw, have " ambient " or long gills.
TERATOLOGY.
The occurrence of six- and seven-valved Chitons has been noted as early as the time of Linnaeus. It is likely that the six-valved were artificial fabrications, although a certain number may perhaps be traced to incorrect drawings. Most seven-valved specimens are due to the soldering together of two valves in consequence of some injury. This is not uncommon, a number of cases having come under my observation. Individuals actually seven-valved are known to occur, although they are far from common. The writer has examined many thousand Chitons, but has seen only two normally 7-valved examples. One of these is figured on pi. 64, fig. 67 ; and as may be seen, it is in no respect abnormal save in the want of one central valve, and the consequent lengthening of the others. There is absolutely no trace
of the missing valve. The absence of a valve produces no striking change in the general appearance of the animal, and it would be easy to pass one by among a quantity. These considerations incline me to think that abnormalities in the valves may be less rare than •opposed.
Injuries to the girdle often produce more or less irregular growth.
-pecies having large girdle-scales, such as Chiton s. dr., or the
large-scaled Ischnochitons, the loss of scales is repaired by the
DJured area of scales much smaller in size, giving
it a singular! \ ! appearance.
Co i \ A ITON OF CHITONS.
Chitons may be looked for on all but sandy coasts ; on these they
are very rare. Some species, like Nutiallina, Enoplochiton* Acantho-
' tc., are found upon the exposed rocks at or near high tide ;
others like most 7 ton*, live under stones between tides or at
lowest water; Km it is only by the use of the dredge that any
roach to a full representation of the Chiton fauna of any locality
can be obtained. e dredging outfit is required, how-
• ver nine-tenths of the species being vegetable eaters, live in the littoral (including the laminarian and coralline) zone, and
generally be taken in 25 fms. or less depth ; although num- bers of species extend their rani:e to or beyond the 100 fm. line, and a few (the genera Lepidoplewrut and Hanleya only) live in the cold and dark abyssal region.
hint knife is useful to the collector in detaching Chitons from
rocks etc. ; and the specimens before they have time to curl
nelves up, should be placed flat on a narrow strip of smooth
wood like a ruler or lath well wetted with salt water, and bound
down l.y windin- with s..ft twine or randle-wicking. This will keep
them in a natural position until the tissues are relaxed, when they
may be placed in alcohol, or cleaned by cutting away the foot and
viscera. If this precaution is not taken they are apt to curl up in a
shape which renders them alm^t useless for dissection or for cab-
-pecimens, for they will break rather than flatten out. A large
l»er maybe thus set on a single stick. If th.-y curl up before
• - t. it is best to put them in a pan of salt water, where will eventually straighten out, if al
HIM. .iii. AI. NOTES ON i in I.ii i HATURE OF CHITONS.
w species of Chitons were known to writer.-, upon shells
POLYPLAOOPflORA,
prior to 1758, the date of LINN.KI;*' Truth Kdition, in which f,,ur species were described. By the addition of the form- ,,f northern Europe, this number is increased to nine in the twelfth edition of the Systema. From this time on, large numbers of ChitODfl found their way into English and Continental collections, and were figured in the works of Chemnitz and others. Linnc classed the Chitons with the Cirripeds and Pholads, before the bivalves ; and this sys- tem persisted in conservative conchological works during the first few decades of the present century. In 1797, SPENGLER, a Danish naturalist, published a good monograph upon Chiton ; but little real progress was made toward a right appreciation of the rank of the group, and the establishment of a natural classification, until BLAINVILLE in 1816 (Bull. Philom.) separated them from the other mollusks as a Class, to which he gave the name Polyplaxiphora. In 1825, Blainville published the article upon Chitons in the Die- tionnire des Sciences Naturelles. In this work an excellent descrip- tion of the entire organization is given, the parts of the valves are definitely named, and the characters upon which the divisions of the genus must be based are stated. The extraordinary insight and genius of the French malacologist are manifest throughout the systematic and structural part of this paper ; but the descrip- tions of species, being unaccompanied by illustrations, have been less useful. QUOY & GAIMARD, in 1834, gave an excellent account of the species collected during the voyage of the 'Astrolabe' ; following the general lines laid down byde Blainville. Since 1834, no systematic work on Chitons of more than local interest, has been published upon the continent of Europe.
In England, considerable species-work upon Chitons was done prior to 1829, but all upon strictly Linn sean lines. In the year 1829, Rev. LANSDOWN GUILDING, residing in St. Vincent, West Indies, wrote a valuable paper, in which he recognized five genera : Chiton, Acanthopleura, Phakellopleura, Chitonellus, Cryptoconchu* ; defining each in an acceptable manner. Shortly after this, the discov- eries of Frembly, Cuming and others, threw a multitude of new and handsome species into the hands of the London conchologists. BRODERIP and SOWERBY described most of the . novelities in the P. Z. S., 1832-1834, and in the Mag. of Nat. Hist., 1840 ; and Sow- erby illustrated them in the Conchological Illustrations, published a little later. These authors knew nothing of internal characters, confining their attention to the superficial features of the shell only.
xvi POLYPLACOPHORA.
The same is true « i:, who in 1847, published a monograph
lining 189 species in the Conchologia Iconica. The figures of Sowerby and Reeve are generally good ; but they ignore inter- nal characters, and tlu-ir «1< '.-mptimis are totally inadequate. J. E. GRAY, in 1847, (Ann. Mag. Nat. Hist., July-August, and P. Z. S.), proposed a system of classification of Chitonidce, embracing many new genera, but largely based upon Blaiuville's article of 1825.
s system is as follows :
V, n-it limit >imj pores or tufts ofsjtiiic* <>n the sides. A9 7 • 'in 1 1 posterior valves divided
'•> several ' 'I of the cent ml -mli-e* into two lobes.
a. Containing Chiton, Tonicia, Acanthopleura, Schizochiton.
b. Containing Corcphium, Plaxiphora, Onithochiton, Enoplo- clii-
['-. Radsia, Callocliiton, Ischnochiton, Leptochiton, subsequently
a-l.lrd by Gray.]
B. The plate of insertion of all the valves with only a single notch on The valves more or less covered ; the hinder valve I [dales of insertion (as in the central valves'), with only a single notch <»i cat-h side, and a concave sinuosity below. a. Contain.- M<»palia. Katharina, Cryptochiton. // Mi • '• >/ >t!i <i series of pores (each furnished with a tuft of spine*) on each side. The plates of insertion of all the valves with only a sin- gle notch on each tide which is sometime* rudimentary.
a. Contains Cryptoconchus, Amicula, Acauthochites, Chiton- ell
Some inconsiderable transpositions and additions were made by Gray in e, 1857. This classification is accepted by H. &
A. Adams, in their Genera of Recent Mollutca, 1858; the two pri- mary «livi-i< dig being regarded as subfamilies ( Chitonince and Crypto- plar, i. ni. The species of their lists in very many cases do
not belong to the genera to which they are assigned, the lists having been compiled without regard to the characters of the insertion plates. The main defects of this system are the greatly exaggerated importance given to the development of girdle-pores, and the imper- fect apprehension of the features of the insertion plates. Some yean before the date of Gray's last paper, J. R. Sm in i \\ORTH, an Englishman by birth, Init nvidi-nt in Switzerland, studied the Chitons carefully in the light of Gray's earlier paper, and published i- of the group (Bern. Mittheil, 1853), making a number of decided improvements in classification.
POLYPLACOPHORA. xvii
At the same time that Gray published his first <-.s.say, Dr. A. TH. VON MIDDENDORFF proposed an elaborate scheme of classification, in an extensive work upon the Siberian Chitons. His divi.-ion- \v«-r«- based upon (1) the entirely internal or partly exposed condition of the valves, and position of the apex of each, (2) degree of immer- sion, indicated by the contiguity or separation of the exposed part of the valves, (3) comparative width of the girdle, and (4) presence or absence of girdle-pores. This classification although worked out with vast industry, is a distinct retrogression from the stand taken by de Blainvillein 1825. MiddendorfF however, did excellent work upon the anatomy of the Chitons in this publication. His arrange- ment is as follows : Genus Chiton L.
(1) Subgenus Cryptochiton Midd. (C. stelleri). (1) Subgenus Phcenochiton Midd. (2) Section Dichachiton Midd.
(3) Subsection Symmetr ogephyr us Midd.
(a.) Poriferi, Ch. (Symmetr.) monticularis Q. [=Crypto-
conchus.] (ft.) Apori, Ch. (Symmetr.) vestitus, pallasi, amiculatus
[— Amicula.] (3) Subsection Afnetrogephyrus Midd.
(a.) Poriferi, Ch. fasciatus Q., larvseformis Blv. [=Cryp-
toplax.]
(6.) Apori, Ch. Isevis Lm. [— Cryptoplax.] (2) Section Hamachiton Midd. (3) Subsection Platijsemus Midd.
(a.) Poriferi, Ch. zelandicus, emersoni, biramosus, etc., [—
Acanthochites, Plaxiphora, etc.]
(6.) Apori, Ch. submarmoreus, tunicatus, alatus, incisus, wosnessenskii, [— Tonicella, Katharina, Ischnochiton, Mopalia, etc.] (3) Subsection Stenosemus Midd.
(a.) Girdle hairy, Ch. marmoreus, lineatus, brandti, mercki,
etc., [^Tonicella, Schizoplax, etc.] , (6.) Girdle finely squamose, Ch. ruber, albus, cinereus,
etc., [=Trachydermon, Lepidopleurus.] (c.) Girdle coarsely scaly, Ch. mertensii, etc., [— Lepido-
zona.] MiddendorfFs names being published simultaneously with Gray's,
xvi li POLYPLACOPHORA.
iot be given priority, save in the case of Cryptochiton ; the other groups are all incongrous assemblages.
rp.ni tlii- time, no \\ork of importance was done on Chitons until ixr>3, when PHII.H' P. CAIMT.NII it (born in Bristol, England, in 1*1 •». died at Montreal, Canada, 1877) published a catalogue of the V rican f..rm- Urit. Asso. Rep). This was followed by
- upon the California!! and Atlantic Chitons, and finally by the preparation of a monograph of the entire group. In
work upon this great undertaking, Dr. Carpenter examined critically the Cumiugian and British Museum collections, contain- ing most of the types of Broderip, Sowerby, Gray, Reeve and H.
.•ii5»; and besides, nearly every collection of any size in England and America, including thoM of A. Adams, Angas, Dr. A. A.Gould,
comb, Jay, Haines, the State of California, the Smithsonian Institution, Museum of Comparative Zoology, etc. The information gained from the examination of this great amount of material was in process of re-arrangement at the time of his death, in 1877, that
ing to the Leptoidea and Ischnoidea being practically com- pleted. A vast amount of work had been done upon the other groups, but his studies of them were far from finished. A large number of drawings had been prepared under Dr. Carpenter's direction, mainly by Messrs Emerton, Foord, and Smith. The whole «»f this J/.S. being devised to the Smithsonian Institution,
\VM. II. DALL published (Proc. U. S. Nat. Mus. 1881, p. 283- 7 tfie genera of Chitons, giving Carpenter's
complete classification, and brief diagnosis of the new groups, of the Carpenterian names therefore date from this time; although in 1873 a large part of them were included by Carpenter in u table printed by the Smithsonian Institution, showing the characters of the " Regular Chitons. " The fact that the distribu- tion of this table was limited to Carpenter's personal friends and correspondents, that it was never advertised or offered for sale, was not sent to most (if any) public scientific libraries nor noticed in
i tific journals, prevents ug from dating his names from the time
publication.
The following table shows the Carpenterian classification in full. The group and family names given by DALL in 1889 ('Blake" Gastropoda) are added in parenthesis.
Order POLYPLACIIMIOL'A (Polyplaoophora Dull;.
Section I. — Chitones regulares BoOHITON] \ I'ull;.
Head and tail plates similarly artinilat* •<!.
A. LEPTOIDEA (Leptochitonidot Dall Insertion plates obsolete or, if present, unslit.
(Extinct forms.)
Jlt'lininthochiton Salter. Pterochiton Cpr.
Qryphochiton Gray. / Loricites Cpr.
Choncchiton Cpr. Probolwum Cpr.
Priscochiton Billings. Cymatochiton Dall.
(Recent forms.) Leptochiton Gray. Hemiarthrum Cpr.
Deshayesiella Cpr. Microplax Adams and An gas.
Hanleyia Gray.
B. ISCHNOIDEA (Ischnochitonidse Dall). Insertion plates sharp, smooth, fissured ; with eaves.
*No pores on girdle. Trachydermon Cpr. Ischnochiton Gray.
Trachyradsia Cpr. Stenoplax Cpr.
Callochiton Gray. Stenoradsia Cpr.
Stereochiton Cpr. Ischnoplax Cpr.
Tonicella Cpr. Heterozona Cpr.
Schizoplax Dall. Ischnochiton s. s. Cpr.
Leptoplax Cpr. Ischnoradsia Shuttleworth.
Chcetopleura Shuttleworth. Lepidopleurus Cpr.
Manger ella Cpr. Lepidoradsia Cpr.
Spongiochiton Cpr. Callistochiton Cpr.
**With girdlepores.
Callistoplax Cpr. Ceratozona Dall.
Angasia Cpr. Pallochiton Dall.
Neivcombia Cpr.
C. LOPHYROIDEA (Lophyridce Dall). Insertion plates broad, pectinated, projecting backward. Chiton Linne. Eudoxochiton Shuttleworth.
Radsia Gray. Craspedochiton Shuttleworth.
Tonicia Gray. Fannettia Dall.
D. ACANTHOIDEA (Acanthopleuridce Dall).
Insertion plates thrown forward. *Plates broad, pectinated (A lophyroidea). Sclerochiton Cpr.
**Plates sharp, grooved outside (A typica). Acanthopleura Guilding. Cwphium < Jray.
Lucilina Dall. Francisia Cpr.
XX POLYPLACOPHORA.
***Plates sharp, smooth (A. /. l)iimplax Cpr. Xiiff'illui'i Cpr.
Mi'ldcwlorjia ('|>r- !»r.
Beaiiella Dall. /V/«/(v//oy»A //ra Guild! ng.
Section II. — Chitones irregulares (OPSICHITONIA Dall). Tail plate abnormal or with a sinus behind. E. SCHIZOIDEA (Schizochltonidce Dall).
Tail valve fissured.
a H. and A. Adams. ochiton Gray.
Aulacochiton (Shuttleworth) Cpr.
F. l*i..\« im<>i:<uin:A (Placophoridce Da\\). Tail valve unslit, internally ridged, mucro nearly terminal. Enoplorhiton Gray. Fremblya H. Adams.
Ornithnchiton Gray. Euplaciphora Shuttleworth.
Plncifthora Gray. Guildingia Cpr.
G. MOPALOIDKA (Mopaliidto Dall).
Tail valve with posterior sinus and one slit on each side. iii ( »ray. Macmidrellus Cpr.
FlaeqphoreUa Cpr. Stectoplax Cpr.
Rather inn ( Jray. Notoplax H. Adams.
thochiton (I^each) Herrm.
H. CRYPTOIDEA (Amiculidce Dall).
With double sutural laminae.
'foconchus Blainville. Chlamydochiton Dall.
Amicula Gray. Cryptochiton Gray & Middendorf.
Amicula s. s. Dall.
I. CHITONELLOIDEA (Cryptoplacidce Dall). Tail plate funnel-shaped. Laminse thrown forward. Chitoncllus Blainville. Choneptax Cpr.
Cnjptoplax Gray. CMtoniteui Cpr.
There can be no doubt that Carpenter's classification is a great advance upon that of Gray. It will be noticed that the primary division of the family is into two great groups: (1) Chitons having the head and tail valves similarly articulated with the girdle, and (2) those having them strongly dissimilar. These two great groups were early recognized by Carpenter, and called respectively Regu. lar and Irregular Chitons.
DALL, in his Report on the Chitons of Alaska (1878), accepts the Carpenterian classification, correcting it in some details, notably in the arrangement of the Amiculoid forms. In the same year he published an extensive and extremely valuable paper upon the den-
POLYFLAOOPHORA.
tit ion i»t' the Ljmup, ^ivini: figure- ;m<l de~eripti.in-< of the radii Ire of speeies representing a majority of tin- 'jenna of ( hit. .us. In 1889,
hall proposed the Buperfamily aod family Dames quoted In pi
thesis in the above table.
The writer j imposes to show in the eoiir~e of this work, that th«- primary division into Regular and Irregular forms is not funda- mental, the Irregular group heini^ polyphyletlc, consisting of g< i derived from several totally distinct stocks. With the exception of the Leptoidea (Leptochitonidie), Ischnoidea (Ischnochitonidse) and Chitoiir/fnidea (Cryptoplaeida-), all of the family groups of Carpen- ter and Dall require dismemberment.
DR. PAUL FISCHER, in his Manuel de Conchyliologie, 1885, adopts the Carpenterian arrangement, with some transpositions, hut reduces the generic names of former authors to the rank of sub- genera and sections. His scheme is as follows. The Carpenterian equivalents being given in brackets, a glance at the above table will show what groups were included by Fischer. Family CHITONID^E. Genus HOLOCHITON Fischer, 1885 [=Leptoidea Cpr.]
Subgenus Eochiton Fischer, 1885 [^Palaeozoic Leptoidea]. Genus CHITON Linn. [Includes Ischnoidea, Lophyroidea, Acanthoi- dea of Cpr.].
Subgenus Tomochiton Fischer, 1885 [Includes the Ischnoidea and Aeanthoidea ischnoidea which lack girdle pores].
Subgenus Porochiton Fischer, 1885 [Includes the Ischnoidea and Aeanthoidea ischnoidea which have girdle pores].
Subgenus Chiton s. s. [== Lophyroidea of Cpr.].
Subgenus Acanthopleura Guild. [= Aeanthoidea typica Cpr.]. Genus ANISOCHITON Fischer, 1885 [Includes Schizoidea, Placipho-
roidea, Mopaloidea of Cpr.].
Genus CHITONELLUS Lam. 1819 [=Chitonelloidea Cpr.]. Genus DIARTHROCHITON Fischer, 1885 \=Cryptoidea Cpr.].
It will be noticed that Fischer ignores the law of priority in the use of generic names. His classification is not otherwise very different from Carpenter's, except that he reduces the genera of Gray and Carpenter to the rank of sections.
M. A. T. DE ROCHEBRUNE, in several papers upon Chitons, pub- lished from 1881 to 1889, has classified the group in various ways, the principal schemes being given below. It is necessary to give in brackets the equivalents of Rochebrune's genera, in order to under-
XXII POLYPLACOPHORA.
stand what hi* family groups really mean.
In (2) iv, 1881, Rochebrune presents
the following arranp-ment:
Family ATAN m<>< HIT.E Rochebr., genus Acanthochites Risso.
1 'an illy ( '11 i; i Rochebr., genus Chcetopleura Shutt, spe-
<gas Cheni. ; and genus Acanthopleura Guild.
Family ('IHTONID.K Gray, genus Tonicia Gray, Lepidopleurus ,so " [— Ischnochiton], and genus Gymnoplax Gray [=Chiton .].
In the /»»,!. ( './/, I/nrn, 1889, the following scheme is given :
Family PIUM-HITONID^E, genus Schizochiton Gray.
Family LOPHYOCHITONID;E. genus Acanthochiton Leach.
Family CH^ETOCHITONID.I:, genus Acanthopleura Guild. ; genus Chcetopleura Shutt. [— Plaxiphora -f- Chaetopleura].
Family ( in i «»MI»I:, genus Tonicia Gray; genus Lepidopleurus rpenter, 1879 " [— Ischuochiton + Trachydermon -f- Callochi- ton !] ; genus Chiton L. [=Ischnochiton -f Chiton s. 8tr.~\.
It will be seen that the ideas of Rochebrune are so opposed to those of the Carpenter and the writer that any criticism of them would be useless. The same Parisian author has published many diagnoses of Chitons believed to be new; but owing to his failure to mention the characters really diagnostic of genera and species, luit little use can be made of his writings. The majority of these forms are still unfigured; and of his figured forms it must be said that IIochebruDe has been signally unfortunate in his artists. Of all the figures of Chitons published by him I have not yet seen a correct one ; most are so radically bad that no dependence whatever can !><• placed upon them. The same is true of his figures of fossil Chitons.
From the above sketch it will be seen that the chief workers upon the classification of Chitons have been few in number, the publica- tions of BLAINVILLE, GRAY and CARPENTER successively mark- ing epochs in the taxonomic history of the group.
POLTPLAOOPHOBJL
Ci, \-iri. M-ION OF Cmi<
The classification given in this work is h:H.-d mainly upon < -har- acters furnished by tlu- articulatm- BUrfeoei «•»' tin- v:ilv«-s. Th«: hard structure in this group is o.mparal.lr to tip ton in the great variety of stresses to whirli it is suhj<-«-t. Karl. valve is not only acted upon by external forces and its i.ody mus- cles, but by the valves before and behind it, and by th<- ^m11' • Hard parts of great complexity have thus arisen, offering to him who can decipher their story clues as valuable for the construction of genealogical lines as have been found in the limb-bones of mam- mals, or the hinge-teeth of bivalve mollusks. The development of the gills, foot and girdle has been given due weight, and for the first time, systematic use has been made of the sense organs of the shell (tegmentum), and the system of sculpture of the latter. The non- differentiation of the dentition throughout the group has prevented the use of that character usually so important.
The Polyplacophora known to us, form a group remarkably homo- geneous, when we consider the vast antiquity of the stock, fossil forms are yet few in number and imperfectly known ; so that all attempts to trace the mutual relationships and descent of modern genera must still be based upon the morphology of living forms. The complex inter-relations of the various families and genera, the number of phyla, and especially the wonderful parallel develop- ments of different stocks, all render a linear arrangement of groups highly unsatisfactory. The accompanying diagrams show the mam facts of classification and descent much more clearly.
It is commonly known that the earlier (Paleozoic) Chitons are without exception, destitute of plates of insertion, and belong, therefore, to the family Lepidopleuridce. This family has survived to the present day, but the species are now few in number and of small size. The higher genera of Lepidopleuridce possess insertion plates on some or all valves, but they are unslit; and it is to tl branch that the genesis of the higher Chitons is to be traced lowest Ischnochitonidce known have already become well differenti- ated by the development of a definite system of slits.
The Ischnoid stock must be regarded as a synthetic or uuspecia ized type of Chitons. In other words the common ancestors of other families of the Chitons (except Lepidopleuridce^ would proba- bly, if known to us, be classed as ItoknochitonM*. From this general- ized Ischnoid stock specialization proceeded in two directions:
XXIV PO.LYPLACOPHORA.
toward greater definiteness in the positions of the slits, and often nl the degeneration of the >h» -11 ; leading (a) through Callisto- placiiuf to the Mopnliidn, and (6) through Acanthochitidce to covered forms, Cryptochiton, and to worm-like forms, Cryptoplacida* ; the last having fewer slits than any other Chitons. In the other direc- tion (II) the slits became generally more numerous, the insertion- plates are roughened for the stronger adhesion of the girdle, the valves increase in general effectiveness as a protective armor, and thrir sense organs became highly developed. This phylum (Chi- nlminates in / vthoplewra, Schizochiton, Enoplo-
chiton, Liolophnra, etc. ; and may be regarded as the highest group of Polyj'hu'ophora.
NOTK. — It must be understood that in cases where the classifica- tion below given differs from that in the descriptive part of this work, the former represents the mature views of the author. Page n the text, should be cancelled, as it was written when but a small portion of the groups there discussed had been studied. The synopses given on pp. 24-25, and 148-149 also require correction.
pris of Classification of the Order Poly placophora. I. Superfamily EOPLACOPHORA. Family Lepidopleiiridce Pilsbry. nus Lepidopleurus Risso. p. 2.
Section Deshayesiella Cpr., p. 16. Genus Hanleya Gray, p. 17. *
Genus Hcrniai •thrum Cpr., p. 19. *
Genus Microplax Ad. <fe Ang., p. 21.
1 1 Superfamily MESOPLACOPHORA. Family l*cl<n<>chttnlti<l<i Pilsbry, p. 253. Subfamily Ischnochitoninse Pilsbry, p. 254. Genus Tonicella ( j.r , p. 40. nis Schizoplax Dall, p. 46. usCallochiton (iray, p. 48. Section Sterochiton Cpr., p. 52. Genus Trachydermon Cpr. p. 67.
I'OLYI'l
Subgenus Cyanoj.hix I'ik, p. 44.
* Genus Ch:<'t<>l>lrur:i Sluittlw., p. 27.
Genni l'all<><'liit«>M Dull, p. 256. Genus Dinoplax Cpr., p. 2~> I.
*
Genus Ischnochiton < Jniy, j>. 53.
Subgenus Stenochiton Ad. & Ang., p. 55. Subgenus Stenoplax Cpr., p. 56.
Section Stenoradsia Cpr., p. 61. Subgenus Ischnoplax Cpr., p. 64. Subgenus Ischnochiton s. s. p. 87.
Section Lepidozona Pils., p. 125.
Section Radsiella Pils., p. 139.
Section Ischnoradsia Shuttl., p. 144. Subgenus Heterozona Cpr., p. 65.
Subfamily Callistoplacinse Pilsbry, p. 259.
Genus Callistochiton Cpr., p. 260.
*
Genus Nuttallina Cpr., p. 277.
Subgenus Middendorffia Cpr., p. 282. Genus Craspedochiton Shuttlew., p. 285.
*
Genus Angasia Cpr., p. 286. Genus Callistoplax Cpr., p. 288. Genus Ceratozona Dall, p. 290.
Family MopaliidcB Pilsbry, p. 292.
Genus Mopalia Gray, p. 294. Genus Placiphorella Cpr., p. 305. Genus Plaxiphora Gray, p. 311.
Section Guildingia Cpr., p. 329.
Section Fremblya H. Ad., p. 330. Subgenus Placophoropsis Pilsbry, p. 313.
Family Acanthochitidce Pilsbry.
Genus Spongiochiton Cpr. Genus Acanthochites Risso. Section Notoplax Ad.
POLYPLACOPHORA.
Section Cryptm-onchus Blv. Section Loboplax Pils. Genus (?) Leptophix Cpr.
Genus Katharinu Gray. *
Genus Amicula Gray.
*
Genus Cryptochiton Midd.
Family Cryptoplacidce Dall.
Genus Cryptoplax Blainv. Genus Choneplax Cpr.
III. Superfamily TELEOPLACOPHORA. Family Chitonidce Pilsbry.
Subfamily Chitoninae Pilsbry. Genus Chiton Linn., p. 149.
Section Radsia Gray, p. 189. Section Sclerochiton Cpr., p. 188. *
Genus Eudoxochiton Shuttlw., p. 192.
Subfamily Toniciinae Pilsbry. Genus Tonicia Gray, p. 194.
Section Fannettia Dall, p. 212. Genus Acanthopleura Guild.', p. 213. Subgenus Mesotomura Pils., p. 218. Subgenus Acanthopleura s. s., p. 219. Subgenus Maugeria Gray, p. 226. Subgenus Amphitomura Pils., p. 230.
Subfamily Liolophurime Pilsbry, p. 232.
Genus Schizochiton Gray, p. 234.
*
Genus Lorica Ads., p. 236. Section Loricella Pils., p. 238.
..
Genus Enoplochiton Gray, p. 252. Genus Onitlmdiiton < iray, p. 244. Genus Lioloplmra Pilsl.ry, p. 239.
i-oi^ ri..\' 0FB
xxvii
l>h<,loy:n<t;<- ,i;,i,tr«m of tfo/0m*fel Olid «nl.J»miHe9 of
Polypfaoophom*
B
|
J3
O
I
I
4 1
I
"CallistoplacinaT
Lepidopleuridw
A diagram illustrating the phylogeny of the genera of Ischnochi- tonina, is given on page 254 ; another illustrating that of i *- era of ChitoMe is given below ; and the descent of the genera ot Acanthoehitida is shown under the head of that family, mutual relations of the genera included in CalMopla,;,,., >. clear to me aud require much further investigation ; but the vie expressed on pages 259, 260 may possibly suggest super-generic groups.
POLYPLACOPHORA.
of the genera of Chitonidcz.
I I
d
a
1
K C
o o
-r .r
r
Liolophurince
ClIITONIDJE
ANALYTICAL KEY TO GENERA OF POLYPLACOPHORA.
a. Fa/re» /ac&mp imertion plates, or if present they are wislit (Lepidopleur*
b. Valves entirely exposed, not immersed, Insertion plates completely absent,
LEPIDOPLEURUS, p. 2.
oc. Head valve having an insertion plate, grooved outside hut unslit; valves ii-viii without plates, -mile xpinuloBe HANLEYA, p. 17.
ccc. Head and tail valves only having unslit insertion plates; girdle thick, sparsely downy, with sut- ural pores HEMIARTHRUM, p. 19.
POLYPLAOOPHO1
bb. Valves partly covered, the exposed portions .-mall, sep- arated MI n,
aa. All valves possessing insertion plates ; valrr\,\ \ii
ing slits ; teeth smooth or bid 4ig fitly roughened bci>< » » f/" r closely, finely pectinated; valves Iwkimj b. Surface of intermediate valves divided into lat« r:i central areas by a diagonal (often in.listinct), extend- ing from beak to outer front angle of tegraentum ; or if this is not clearly the case, the posterior valve has un even, crescentic series of well developed teeth ; all valves having slits.
c. Posterior valve having a crescentic series of well developed teeth (Ischnoch \\m> >
d. Anterior and side slits not corresponding in position to external ribs (Ischnochitonina.) e. Valves porous at the eaves, appar- ently smooth outside or nearly so ; teeth sharp, smooth; girdle naked, sparsely hairy or densely covered with elongated corneous bodies, the visible ends of which appear like diamond- shaped scales (Tonicelloid group). f. Sutural plates not connected across the sinus ; girdle naked ; side-slits single ; gills shorter than the foot.
g. Median valves having a me- dian slit filled with carti- lage, SCHIZOPLAX, p. 46. gg. Median valves normally < al- cified, TONICELLA, p. 40. ff. Sutural plates connected across the sinus, or side-slits several, or both ; girdle either sparsely hairy, naked, or with compact diamond- patterned covering; gills as long as the foot, CALLOCHITON, p. 48. (This includes the typical forms of Trachyradsia, p. 83.) jgjf. Girdle with chaffy scales or pap-
XXX POLYPLACOPHORA.
illose ; gill-row short or long,
TRACHYDERMON, p. 67- ee. Valves solid at eaves, generally with beaded sculpture ; teeth sharp, often rugose outside; girdle leathery with few or many hairs or spiculse, never scaly ; gills as long as the foot (Chat;* - pleuroid group).
/. Sinus squared, the sutural plates not connected across it; girdle hairy or naked.
g. Mucro in front of the mid- dle, CH^ETOPLUERA, p. 27, [and appen'H.r.
gg. Mucro decidedly posterior,
PALLOCHITON, p. 256.
ff. Sutural plates connected across
the sinus ; girdle thick, bearing
minute clumps of short spicules,
DINOPLAX, p. 254.
eee. Valves solid at eaves ; girdle densely covered with imbricating scales, rare- ly elongated like fluted pillars (Isch- noid group) ISCHNOCHITON.
/. Shell much elongated, narrow (gills short at both ends ; foot no- tably dilated and produced in front, at least in some of these sections).
g. Girdle scales uniform ; mu- cro near the middle
h. Valves longer than wide, roundly arched, with several side slits; animal Julus-like,
Stenochiton p. 55. hh. Less elongated; Amer- ican forms
Stenoplax, p. 56. gg. Girdle scales very unequal ;
POLYFLAOOFHOfl
raucro el
/ ff. Shell not ^n ally .-IniiL
g. ( iinllc clothed with large ami small iiit'Tiningled scales, Heterozo gg. Girdle scales regular, uni- form.
h. 1 slit on each side of median valves i. Girdle scales flat, lachnochiton, p. 86. ii. Girdle scales very convex,
Lepidozowi, \>. 1 '_'•"». hh. 2 or more slits on each side,
i. Girdle scales flat, Eadsiella, p. 139. ii. Girdle scales con- vex,
Ischnoradsia, p. 144.
dd. Anterior and side slits corresponding in position with external ribs (Callistoplacinae). e. Surface of valves having strong radial ribs ; girdle densely clothed with im- bricating scales,
CALLISTOCHITON, p. 260. ee. Surface of valves granulated or peb- bly ; girdle not densely imbricated with scales.
/. Anterior valve with more than 7 slits ; sinus very spongy ; mu- cro posterior,
NUTTAI.I.INA. J>. -77.
ff. Anterior valve with ."> slits ; mu-
cro subcentral, not posterior,
g. No sutural pore tufts.
CRASPEDOCHITON, p. 285.
gg. Sutural pore tufts present,
A NC.ASIA, p. 286.
\X.\ii POLYPLACOPHORA.
e> f. Surface of valves wrinkled or ribbed ; girdle naked except for hairs or cor- neous spines.
/. Valves having very strong radial ribs; girdle naked, with sutural tufts, CALLISTOPLAX, p. 288. jj. Valves not very strongly sculp- tured ; girdle tough, with corne- ous curved spine-like processes, CERATOZONA, p. 290.
Posterior valve having a sinus behind, with one slit or none on each side ; girdle hairy or nude, never scaly (Mopaliida'). See key to genera on page 293. 66. Surface of intermediate valves divided into a narrow dorsal area, and latero-pleural areas, the latter formed by the union of the lateral and the pleural (or sides of the central) areas ; valves more or less covered by the naked, spiculose or hairy (never scaly) girdle ; gills gen- erally short (Acanthochitoid phylum). c. Posterior valve either having well developed slits, or a posterior sinus, or both ; not funnel-shaped, anterior valve with 5 or more slits (Acanthochiti- dce, see next volume for species).
d. Valves not completely covered by the girdle, the first 7 having their apices posterior and marginal.
e. Anterior valve having 5 regularly placed slits; exposed portion of each median valve much longer than wide. /. Girdle provided with pores bear- ing tufts of bristles ; posterior teeth wanting or irregular
ACANTHOCHITKS.
ff. Girdle naked ; posterior valve with 6 slits, the teeth even, spread- ing LEPTOPLAX. jfjfjf. Girdle spongy, produced forward as in Placiphorella
SPONGIOCHITON.
POLYPLACOni«H:\.
ee. Anterior \
larly spaced, mon- than •"> ; j.o.st«-i valve with :i median angular t its edge with several uni-<|ual notched or slits; exposed part of valves flask- shaped I\ \iiii eee. Anterior valve having 6-8 un< slits; posterior valve 2 slit- ai, median wave; expoM.I part of each valve far shorter than the ridge of the valve, heart-shaped A.MICULA. dd. Valves completely covered by the girdle,
their apices not marginal, CRYIT<M m b. Median valves partly lacking side slit- ; tail valve with 2 or no slits
cc. Posterior valves without distinct slits, and huvini: no posterior sinus ; more or less hollowed out and funnel-shaped ; anterior valve with 3-5 slits ; body rather vermiform ; gills short, posterior (Cryptopla- cidce ; see next volume for species).
d. Valves small, narrow and sagittate, gener- ally partly disjointed ; not covering the body to any considerable extent
CRYPTOPLAX.
dd. Valves transverse/all strongly imbricating ; covering a considerable portion of the upper 'surface CHONEPIAX.
aaa. All valves, or valves i-vii, possessing insertion plates cut
teeth by slits ; the teeth sharply sculptured or "pectinated " out- side by fine vertical grooves (Chitonidce). b. Valves lacking eyes (Chitoninoe).
c. Girdle scaly CHITON, p. 141».
cc. Girdle leathery, with short bristles
EUDOXOCHITON, p. 192.
bb. Valves having eyes ; posterior valve not deeply simiM-d behind, its insertion plate developed (Tonic! ;
c. Girdle leathery, nude or nearly so,ToNiciA. j>. L94, cc. Girdle covered with calcareous spines or spinelets,
ACANTHOPLEURA, p. 213.
bbb. Valves having eyes (rarely subobsolete) ; posterior
XXXIV POLYPLACOPHOKA.
valve either having a deep sinus behind, or lacking the insertion plate altogether (Liolophurince).
c. Median valves having eyes developed only on the diagonal ribs. Sinus notably narrow and small. Insertion plates of tail valve a low, rounded, rugose ridge more or less notched, slit or waved upward in the middle behind, or sharp, long and pectinated.
.ves developed on radiating ribs of all valves; the ribs of head valve correspond- ing to internal slits ; girdle having minute spines ; shell elongated, posterior valve and girdle slit behind SCHIZOCHITON, p. 234. '/</. No eyes on head valve, its riblets not corre- sponding to slits ; girdle densely scaly
LORICA, p. 236.
cc. Eyes developed upon the lateral areas. Sinus wide and large. Insertion plate of the tail valve reduced to a smooth ledge or ridge, having no posterior sinus or wave.
d. Valves polished or eroded, dark brown out- side and within, having excessively minute eyes scattered over lateral areas and head valve (when not eroded) ; interior very densely, minutely and peculiarly grooved and punctured. Girdle fleshy, bearing sep- arated rude scales, ENOPLOCHITON, p. 252. dd. Valves polished, colored outside, porcella- nous and smooth within, having the eyes disposed in radial bands on each lateral area and the head valve. Girdle leathery, microscopically velvety,
ONITHOCHITON, p. 244.
ddd. Valves lusterless, granulated, having minute eyes scattered over the lateral areas, sides of the central areas, and head valve. Gir- dle densely covered with stout calcareous spines LIOLOPHURA, p. 239.
LEPIDOPLEURID2 .
Lap totVfca CARPENTER. — Lept<n-hitnni<lti IJ.M.I., ' Dlake1 p. -ill. L889.— Genui 7/Wor/,;/o// FISCHER, Manuel «!«• Com-hyl. p.
*77, 1 -
ChitODS in which the head and tail valves arc similarly articu- lated, and having the insertion plates either obsolete, or if pn-
without slits. Girdle finely acaly or bristly ; gills short, posterior. This family is readily known by the entire absence of insertion- plates, or the Min pie, nimlit character of them when present. The living species are few in number, and mainly either northern in dis- tribution, or living at considerable depths. All of the Palaeozoic Chitons yet known belong to this family, and this fact, together with the weak, imperfect articulation of the valves, causes us to regard the Leptoids as the most primitive of the existing groups.
Synopsis of Genera.
A. Valves entirely exposed, r>ot concealed by the girdle. B. Girdle without pores.
Genus I. LEPIDOPLEURUS Kisso, 1826.
Insertion plates absent. Girdle with minute, gravelly, smooth or striated scales, usually with a marginal fringe of longer scales. Type, L. cajetanus Poli.
Section Deshayesiella Carpenter, 1878. Girdle having delicate spines and chaffy scales. Valves curved and beaked ; sutural plates and sinus as in Leptochiton. Type, L. curvatus Cpr.
Genus II. HANLEYA Gray, 1857.
Front valve having an insertion plate which is grooved outside but without slits. Intermediate and posterior valves without inser- tion plates. Girdle finely spiculose, without pores. Type, JL huii- leiji Bean.
BB. Girdle with pores at the sutures.
( ienus III. HEMIARTHRUM Carpenter, 1876.
Head and tail valves having smooth, unslit insertion plates, the intermediate valves without insertion plates. Sinus broad and 1 (1)
2 M i'iiM>i-i.i:rRU8.
spongy. Girdle downy, having small, tufted pores. Type, H. set- ulosiun ( 'j.r.
A A. Valves partly covered, the expose< small and sepa-
rated.
\\\( K< H'LA X Adams & Angas, 1804.
Insertion plates smooth and thin, well developed in all the valves, ml plates and sinus obsolete. Girdle thin, most minutely gran- ular, not jM»riferous. Type, M. proyiAd. & Ang.
Gem.- I. LEPIDOPLEURUS Riaso, 1826.
pleurus Risso, Hist. Nat. 1'Kur. M.'rid., iv, p. 267, 1826,
in : t species /,. c,ij*t>tnns Poll). — SARS., Moll. Reg. Arct.
., 1*7*, }». 1 in. Nut L'-ftidoplenrus of H. & A. Adams, Car-
: 'all. ft •i/.—Lrptorhiton GRAY, Proc. Zool. Soc. Lond. 1847,
j». 1 H I1.. M.. p. 182, 1857.— CARPKM I:K, J/& p. 1,—
- ; . Mus. 1878, p. 3\±.—Leptochiton, in part, of
H. A A. A i. A MS, Gen. Rec. Moll, i, p. 473, and of CHUM ,
Manuel, i, p. 381.
In / itioii plates are completely absent; the
girdle is narrow, with minute striated or smooth scales, and some _rer scales at the edge. The present genus has hitherto been known as Leptochiton, but
:vji-i-tioM of that name seems to be inevitable as will be seen
DO the following:
// • '. of the name Lfj'irl»i>/>-urii.<. The first publication of
Lepi- l in Kisso's Histoire Naturelle des principales pro-
!••• Mi'ridiojiale, vol. iv, p. 267, 182G, where ii is
•«NJ as of Leach's ww. It is character! zed as having the triangular lateral areas elevated and the girdle covered with small scales, and in it are includ<-d .711) L. cayetanns Poli, (712) L. coral/inn* n. sp. and (713) L. sul&itus n. sp. Of these, the first species belongs to the v '• . Mib.-e.juently named I,e]ttocliiton, and the
two latter belong to the genus Chiton as restricted to Lin nuns' type. It is there!'"!.' evid.-nt that if u>.-d at all. the name Lepido- plcn ;.rojM-rly be ii>,-d foi | ,,,,lv. It is greatly to
be regretted that it was not so used by < iray, as much subsequent confusion would have been avoided. The rej.ublication of the
i.i PIDOPLE1 i '{
•Trims in ( Iray's edition of L.-arh' I/,- - jn
'. need not he omsidrivd here ai ii \\-.\- no hcarim: upon mmi.-n- rlatun>. In 1868, Me«r», II. ami A. Adams, in tli«- <, Recent Mn//nwt, adopted llisso's nanir for a I:ir_r(i li-t 0 mainly of Ttehnochitoni, l>ut inrludinir al
Lcpfnchitttn, etc., among them L. m/v/. /////.-• I'oli. •
priitrr in his later writing used LepidopUufW !•• rover tliat '_rroiip of Isrlmorhitons liavini: the girdle clothed with large, .-niooth nm- \ •« A <caK-s, like those of the typical Chitons. Nothing can !•«• -aid in tiivor of this use of the name, for Carpenter expressly states that the species cited by Risso are excluded from the group as re-habili- tated! It is, therefore, obvious that Lepidopleurus Cpr. is a totally distinct group from Lepidopleurus Risso. No argument is ne<-di-d to show the untenability of Carpenter's position. In 1880, Cam-, in his Prodromtu Faunce Mediterranean, has used Lepidopleurus as a subgenus under Chiton (which he places in the Ischnoidea ! j, and has included in it species of Trachydermon and Ischnochiton, as well as Leptochiton cajetanus. In 1878 G. O. Sars correctly restricted Lepidopleurus to the genuine Leptochitons.
L. CANCELLATUS Sowerby. PL 3, figs. 54, 55, 56, 57, 58.
Shell small, elongated, much elevated, regularly arched, not anirled. Orange-ashen or .whitish.
Anterior valve radiately, evenly, very finely, granose-1 irate.
Central areas of the intermediate valves having distinct longitu- dinal, fine, close granulous line, the granules being sometimes arranged in transverse lines also, giving a latticed appearance ; lat- eral areas distinct, decidedly raised, convex, having radiating but rather irregular rows of granules.
Posterior valve with central elevated apex ; posterior slope con- cave. '
Interior white, the sutural plates small, triangular: juiral sinus very broad.
Girdle narrow, densely beset with delicate, scarcely imbricating or striated, scales (figs. 55, 57).
Length 5], breadth 2 2 mill.; divergence 80°.
Northern Atlantic and Arctic Seas. — Britain ; Norwegian Coast in ">0-100 fms. ; Lofoten Is. 300 fins. ; Greenland: South to Gulf of Lyons, Vigo, Spain (and Dalmatia /). Northern I'lirific. — .-1 tnskn, at Unalashka, Shumagins, Port Etches and Sit/:n II<;r/i<>,\ o'-loo t'ms.
4 LEPIDOPLE1
ii m*.}. Conch. 111. f. 1()4-
3& HAM
Brit, M-'ll. ii. I>. -Jl(>. : Brit. < «nch. iii,
p. -J17: v. p. l'. I. — Lr/.i'lnjJtuirns r'tnrellntn* BARS,
Moll. .. p. IN. t. 7. f. 6; t.i,f.&.—Lq)tochiton
i/>, p. :;.- - Du.i.. Proc. I". 6. Nat. Mu,. 187*
Linn..//'/' Hanlcy. — Chiton as ellus MIDI.., not .if Lowe.— ( An r., n..t Payr. — / Ch. isliimliru*
Tli without careful inspection will usually be confounded
wiih small specimen- of Tr'irliinlcnmiH iiUnis, but a --lance at the sculpture i- -utlicient to separate it. From several other species of
ailily distinguished, and a magnifier is indis-
•ahlr. The ditlerential characters are as follows: The pu.-tules which constitute most of the sculpture are arranged like overlapping coins or a solid-linked chain in lines which in the 1 area an- nearly parallel with the longitudinal axis of the animal. The lateral area- are distinct, and the pustules upon them in rather indistinct lines radiating toward the lateral of the valves, at nearly right angles to the lines on the dorsal ilpture on the mucro is more delicate than elsewhere. The apex of the po>terior valve is not sunken and is not so sharp -i>ecies compared with it here ; the girdle is scaly, with -mall, spino^e, transparent scales near the margin. There live Lrill plume- on each side, prominent and near the vent. pear to be two fenestra on each side. The lateral areas .(her portions of the valves are nearly always colored with blacki-h or frrniL'inoiis patches, but these, as with Tr<i('lii/(lcnnnn n/bn# >eem to be really c<.mpo>ed of extraneous matter. In L. fuli- Ad. A: live., the pustules are much smaller, and while hav- ing a Lfeneral longitudinal arrangement on the dorsum, do not form llariy defined TOWS Or chains. The areas are not raised above the dor-uni. The shell is much larger and more elevated, with a :iken and «|iiite sharp posterior mucro. Tin- other nine ii"i raided but about them the sculpture is more regu-
larly aliened than eUewhere. 1 have compared the valve- of a typical >|M-< -iinen from Korea, collected by Belcher. I figure
of the sculpture i- very bad. as are nio-t of his details. L. alveolus di-tinct though it has been confounded with
thi-. It- sculpti;! and rather ni..iv Sparse,
LEPIDOPLEU1 ."i
isolated puMiilr-, alxoliitcly irn-Lrular in di-l ril.ul i< •: same .-!/«• on the mucro ;in<l eUr\\h« -re. N«.\\l Iille>. The aicll of tin- back is | >eci 1 1 ia ll y P>und. the lat- : not rai^-d ami barely di>tiniMii>hai)le. The girdle seem I have compared typical examples.
L. ooncmnttt Gould, from the types, ifl of i diilen-nt color, and has a much M router and different sculpture like line- of i
L. inft'nir.rii.'S ( 'arpenter and var. rui/nln.* ( 'pr., are more like cinnii*, hut di-tin^-mslied from either by the peculiar ^irdl- with sul>e<|iial scales.
L. nexn* ('arpenter more nearly resembles c.ancellatns but the sculpture is of separate, not lapping, rounded rhomboidal pu>n the mucrones are much more pronounced, and the white ground i- prettily marbled with black and gray inherent coloration. The name cancellattu is a misnomer, since it is only in certain lights that any trace of reticulation can be observed faintly. The young are flatter than the adults. It bears no resemblance to L. asellus, with which Middendorff united it, probably without a comparison.
L. arcticus of Sars seems to be a finely grown variety of this spe- cies, if one may judge from the figures; at least, no differential characters are given which seem to be of a permanent character, and not subject to variation within the limits of a species.
The gills occupy a space corresponding to the posterior quarter of the foot ; there are about eight or ten on each side. The mantle edge is plain and thick. The veil is plain. The muzzle is rounded, with a little papilla at the posterior corner on each side (Dall.)
L. ARCTICUS Sars. PI. 3, figs. 59-63.
Shell subdepressed, dorsal keel obsolete, lateral areas little con- spicuous. Posterior valve smaller than the anterior, subrhom- boidal, roundly produced in front. Median plates throe tim- long as broad, the front margin truncate in the middle. Surface of the valves nearly smooth, indistinctly granulose. (Sars.)
Length 12 mill.
Spitzbergen, Greenland, Vadso and Finmark, 20-10* •
Lepidopleurus arcticus SARS, Moll. Reg. Arct. Norv. p. 11-, t. 7, f. 7.— Chiton aretiew JEFFREYS, P. Z. 8. 1882, p. 668.
Dall, judging from the description and figures, considered tl form of L. cancellatus. Jeffreys, who found the - D the
b LEPIDOPLEUBUS,
' Lightning' dred-ini:-, -ays that it differs from the white variety «if euf [--ascllus] in its comparatively greater length and more
raised or arched form, in the less distinct or regular catenation of granules which OOVer the surface, and in the prominence of the
lateral areas.
I.. \i.\ r.M.rsSars. PI. 2, figs. 23-' H .
Shell quite convex, hack equally arched, without trace of a keel
or defined lateral areas : valve- rather elongate, the posterior larger
than the anterior valve, half-round, truncated by a straight line in
t'n.nt: median valves subequal, their posterior margins straight,
rior margins lightly emarginate in the middle. Entire surface
1 witli minute ovate tubercles, regularly disposed. (Sars.)
Length 16 mill.
North Atl'tntir at Bergen, Lofoten, Finmark, 150-300 fms. ; Bay
of Jiiwitt, ] i_>n-6fi4 fms. ; Gulf of St. Lawrence betiveen Cape Rosier
\ 1C. /,„/„/ of Anticostild., 220 fms.; St. George's Bank,
',e, 150finfl,
•dveolm (SARS ms.) LOVEN, Ind. Moll. Lit. Scand. p. L'7, 159, 1846. — I ii PREYS, P. Z. S. 1882, p. G68.—Lepidopleurus alve- olus G. O. SAI:>, Moll. Reg. Arct. Norv. p. 110, t. 7, f. 3 ; t. i, p. 7, ISlS.—Leptochitn,, alveolus DALL, Proc. U. S. Nat. Mus. 1878, p. :I17.— II A i 'DON, Challenger Rep. vol. xv, p. 12.
L. i-i.i:«;i: \vvrrs Dall. Vn figured.
Shell elongated, moderately elevated, regularly arcuate, without jugurn. Pale wax.-n, sometimes white. Valves wide, without • .s. Front and back valves more or less concave; posterior valve without elevated apex. Sculpture as in L. cancellatus, but th«- -ninnies larirer, lateral areas less defined. Sutural plates elon- gated. < iirdh- wide, densely beset with delicate scales. (Dull.')
1 Qgth !_'. breadth 6i mill.
Near Dominica, West Indies, in 138 fms.
Lepfoekiiok J,' r<jr<ntat,i$ I)\F.L, 'Blake' l\ep. p. 414, 1889.
This fine species is nearest the Atlantic L. c<mre/l<itu* Sc.werby, :"i«l ' Ad. <fe Reeve. It differs from both
in its concave or excavated, instead of convex, terminal valves, in the absence or obsolete condition of the posterior mucro, in its much larger and inure regular granules, and in the subdeprcsscd appearance also of the {.art of the median valves near the girdle on each side. It is larger than <,,„,, //,,/„.< all<i smaller than ;'////-
i.i ri ix >ri i i i
, and without the dinu'V hlaekish pai nt in- of either. / crl/ntu.< is narrower, higher, and \\itli a -harper medi:m aiiL'Ir. |M L. fnli t/iiiiifn.* the middle valve- are ihortei from front t<. liaek, tli.' sutural lamina- .-mailer and much more tri;iii'_:ular. Th- siirii of a niucro on these valves, hut in /,. y,/-/-///-//,,,////.* t in TO \» a beginning of one, <|iiitc perceptible. The latter i.- a pn.pi.rt ionallv wider and. Hatter species, with a stronger and more prominent girdle densely set with elongated silvery scales like short <titf'_rr;i\ 1 these form a pretty fringe at the periphery. The sculpture foil tlui pattern of I,, canc.dltitn*, hut, the lateral areas are less r|<arl \ defined, the granules are more clearly cut, more regularly arranged and larger than in any of the species hitherto known. There are twelve gills on each side, reaching forward to about the middle of the sixth valve. (Dall.}
L. BELKNAPI Dall. PL 1, figs. 18-22.
Shell elongated, much elevated, dorsally angled; whitish, more or less tinged with ashen or black. Valves elevated, with distinct apices ; mucro central, conspicuous. Sculpture as in L. alveolus, but the granules of the dorsal areas sparse, and disposed in quin- cunx. Posterior valve concave below the apex, sinuated behind. Girdle narrow, having delicate spicules toward the margin. {Dall.)
Length 10, breadth 3 mill.; divergence 90°.
North Pacific Ocean in lat. 53° 08' N.t Ion. 17° 19' IF., at a depth of 1006 fms. ; off Cape Bolinas, Luzon, Philippines, 1050 fins.
LeptochitonbelknapiDAL^PTOc. U. S. Nat. Mus. 1878, p. 1, Jan., 1878 ; I. e. p. 317. — HADDON, Challenger Kep. xv, p. ID, t. 1, f. 2 ; t. 2, f. 2.
This specimen much resembles L. alveolus, to which I at first referred it. A careful microscopical examination, however, shows differences which I am disposed to consider specific; but I have but one specimen, and others might show modifications in the^e particulars. The differential characters are as follows: In afr- the pustules are distributed evenly, closely and in no pattern what- ever, all over the surface. In belknapi, they are more widely separated and arranged in quincunx on the dorsuin, the s\ >eeming to radiate from the median dorsal line. In a/tW//.< the lat- eral areas are barely perceptible. In belknapi they are raised, con- centrically rugose, and the pattern of the pustular arraiiL.rcm»! different and more irregular than that on the dorsum. In belktiapi
LEPIDOPLEUR1 3.
thin, narrow, and sparely 96l with small pel- lucid ipiculea Dear the mar-in. Ti ior mucro or up.
lllr [Tile, in ^flop^ is prominent, overhangs a shallow
J ami fV..,n its point there diyerp- anteriorly t\mr depr
the anterior lateral an-l.-> of tin- plate, the
inn. :idi-tant from each ot her and the outer Iiu,->. I'.etween
the plat.- ^ >welled, formini: three rounded ridges,
ruard like th.- leaflet- of a trefoil <»r clover, Nothing
•iiblm- thi> ha> been •»!>«• rvcd on any of the other species which
have oome under my notice. The >,,ft parts in spirits appeal- to
Other Bpeciefl compared with it. It is evidently adult
Tl'' Bent the form dredged l.y the 'Challen-er1 ,,tr
mt Thilippines. Had.lon describes these specimens a< fullcws: S|l(l11- l>nttl.-. cloaelj Covered with larire, round, .smooth tuber- i an angle of about 110°. Sutural lamina- all.
r valve.— With a few irregular lines of «rrowth, thickly
•A ilh irregularly disposed tubercles.
'li:ltt> v^' ntral areas: with a shallow depression
: -h Bide "f the median rid^., which givea the latter a pinched
: his depn-sion is mo>t apparent at the hinder border
The tubercles have a -eneral arrangement in
ol.li.ju,' liiu-s ra.liatin- forwards from the keel and at the same time
i" li' Btric to the umbo, but these two series of lines are not
'. and the tubercles often appear to be irregularly dis-
!' short eoncentric rows usually demarcate the
1 the lateral areas. Lateral areas: scarcely ap-
ndicatin.i: a line of -rowth occurs at a short dis- Mle; tubercles irregularly disposed, with a ten- '.. however, to concentric lines.
With a small subeentral umbo, behind which Interior area: the lateral lon-itudi-
""I '' tejugum to be slightly prominent and thus
give^ the anterior inewhat trilobed appearance; the tuber-
Bnded keel. Posterior area; with ooncen-
i and el-.-elv >rt tuber,
. thickly covered with delicate small oval scales; :ini1 more pointed scales occur along the border
and in th- !vr>
8
.- ( irayish-whitr. Si/.,-. Len-th about rjmm.; hivadlh ~> mm. ; hriirhi
inin.
s. Fornmi- a short po-terior n»w, ^i\ <.r seven in number.
This species is considerably lar-er and OOartOT than tin- |>i
(L. benthut'). The tubercles are twice the size and <•!• ther,
The shell IB also Comparatively >harply keel.-d, instead of having a uvntlv rounded appearance.
L. BEVTHU6 Haddon. IM. 1, ligs. 1-13.
Shell.— Delicate, brittle, surface with minute inc.,n^,i(MiMUs >ln.rt ridges more or less radially disposed, and studded with small tul.er- cles3. The sides meet at a rounded angle of about 100°. Sntural lamina- small.
Anterior valve. — With minute scattered tubercles, which | towards the apex into low tubercular ridges, having a concentric arrangement.
Intermediate valves. — Central areas: The minute surface ridges, when visible, are longitudinally disposed on the jugum, but be. radial or oblique on the pleura. The tubercles are round on the jugum, but becomeVomewhat oval on the pleura, and there appear to&be concentrically arranged, although in some valves they seem to more or less regularly diverge from the apex. Lateral areas : The surface ridges are radial and more pronounced than elsewhere. On the upper portion of the areas there are transverse low ri placed further apart than the former ; these ridges by bein- inter- rupted gradually pass into tubercles. The tubercles are round, distinctly smaller than in the central areas, and more scattered.
Posterior valve.— With a small central umbo. Anterior an a : With concentric tubercles, as in the lateral areas. Posterior area : Similar to the anterior valve.
Qirjle.__NarroWj with delicate scales, which form a minute fri at the edge.
C0lolv_Greenish-white with one or two irregular reddish-brown
flecks.
Size.— Length, 8 mm. ; breadth, 3.."> mm.
Northern 7V//.V, L«t. 35° 41' N., long. 157° 4? K.. i.. 2300 fas.
/.. henthus HAD., ('hall. K.-p. xv, p. H>, t. 1. f. 1. t. 2, f.
dills.— Seven in number, extending between the prominent anu> and postero-lateral angle of the foot. The gill row ifl ..n.—venth
10 LEPIDOPLEURU8.
of the total length of the body, the proportion with regard to the
n <>t* the foot is 1 : 4.5. Tin -y are of moderate size, the middle
being the largest, slightly decreasing behind but much more so in
L. n i i '.IN \rt\s Adams <fc Reeve. PI. 4, fig. 88.
Shell elongate, elevated, whitish, tawny-ashen sometimes soiled ; apices * T..I|« •(! ; juirum rounded. Mucro moderately elevated, posterior slope very concave ; jugal area hardly defined ; central area hardly sculptured ; lateral areas quite elevated, frequently sculptured with irregular concentric incremental wrinkles ; jugal sinus wide and .-traiirht. < n'rdle narrow, very thin, thickly covered with very deli- cate small and fugacious scales, which are somewhat elongated and purpli>h. (CJpr.) Length 20, breadth 9} mill. ; divergence 90°.
Korea.
( '1,,'tw, fH/if/htntu* AD. & RVE., Conch. Icon. t. 26, f. 174, 1847.— Lept<><-Itit«)i fnflf/inatus A. & R., CPR. ms. p. 4, 5. — DALL, Proc. U. t. MIIS. 1878, p. 318, 316.
This specimen is an approach to Stenoplax in its outward form and the character of its girdle covering. The scales appear smooth, ami have the shape of those of Stenoplax. It has a curious general resemblance to Trachydermon albus, but the absence of insertion plat*-- at once distinguishes it. The concentric furbelowing at the sides i> variable. (Qor. from B. M. specimens.)
See remarks under L. cancellatus for further distinguishing char- acters of tli is species.
I.. • \ni. 1.1 •- K« ve. PI. 4, fig. 87.
Shell ovate, attenuated anteriorly; terminal valves and lateral areas of the rest concentrically ridged, radiated with minute gran- uli-s central areas very finely grooved and cancellated, whitish, liga- ment horny, arenaceous (Reeve.)
Habitat unknown.
C. catillus Rv. Conch. Icon. t. 23, f. 159, lS47.—Leptochiton
... CPB, .UN. p. ii.
Miu'ht e;i>ily IK- taken for *trnmtnens Sby. outside. Coarsely
granose-1 irate, like the Mogador specimen [L. granoliratus] ; girdle
gravelly. The sculpture consists of longitudinal granose lira1 upon
ami radiating gltmofe lira- upon the lateral areas.
No insertion plates, but the line of them is rugose. Length 9*,
rgeooe 110°. Jugum rounded. (Q?r.)
ii PIBOPL1 iKUS. 1 1
L. CONCINNU8 Gould. I'njif/nrnL
Shell minute, reddish, elliptical, vaulted, all over punctate [ LM
lose], the points arranged in radiating, nirvmi: B6rie0; lateral areas hardly elevated, longitudinally waved, l-'mut valve oretoentlC : posterior valve with an acute umbo, concentrically waved. < ,'mlle narrow, buff. (Old.) Length 8, breadth r, mill.
Butural plates small, subtriangular ; jugal sinus very wide, flat ; scales of the girdle delicate. (Qpr.)
Hakodadi, Japan, laminarian zone, on shells and
C. (Leptochiton) concinnus GLD., Otia Conch, p. 117. — Lepto- chiton concinnus CPR. MS., p. 3. — DALL, Proc. U. S. Nat. Mu~. p. 318, 316, 1878.
L. NEXUS Carpenter. Unfigured.
Shell small, whitish-ashen, valves gothic-arched ; lateral areas scarcely defined; entire surface ornamented with series of sulujuad- rate granules, the series longitudinal upon the central, radiating upon the lateral areas and end valves, very close, scarcely inter- rupted. Jugum elevated, subacute; umbones inconspicuous. Mucn. conspicuous, median. Inside with strong sutural lobes and a wide plane sinus to the middle valves; insertion plates obsolete. Girdle having narrow, close, striated scales and needle-shaped, crystalline bristles here and there and around the margin. (Q?r.)
Length 7s, breadth 4£ mill.; div. 90°.
Catalina Island, California, 20-80 fins.
Leptochiton nexus CPR., Rep. Brit. Asso. Adv. Sci. for 1863, p. 650,1864; Proc. Cal. Acad. iii, p. 212, 1866; ms. p. 2.— DAM.. Proc. U. S. Nat. Mus. 1878, p. 316, 319.
A variety is prettily variegated with olive, has stronger sculpt- ure, and the valves slightly beaked. The spicules which appear on the girdle among the striated, elongated scales, are very numerous. It is curiously like the young of Ischnochiton radians. (Cpr.}
See notes under L. cancellatus for comparison with that species.
L. RUGATUS Carpenter, n. sp. PI. 3, figs. 67-70.
Oval, rather convex, the lateral slopes nearly straight, doi-al ridge broadly arched. Front and back valves and lateral areas of the intermediate valves sculptured with excessively fine radiating striae which are feebly granose, and having well-marked, coarse, con- centric wrinkles; central areas having an equally minute sculpture
ll* LEPIDOPLEUBU8,
of longitudinal Bubgnuno0e striae. Macro sabcentral ami prominent. Tlit- lateral areas are slightly ra:
\. bivadth 7 mill.; <livergence 100°. i/. .-• ray, ''<//.. t» T<><1».< Santos Bay, L. C<tHf»rn'i<t.
/.. ft rntj'itn.4 ( 'i'i:. .U.S., p. 3.
This form resembles somewhat the 7>. granolirotiu, but it is much finely -culptinvd. the arch of the valves is narrower and the al areas are less stnmirly marked by concentric- wrinkles. It i-- likely that (lie following is merely the young of this, but I have not Keen able to compare typical specimens of internexus.
L. i\ irpenter.
Sh»-ll similar to L. nexus, but much smaller, orange colored. Valve- i. -iilarly arcuate, without jugum. Sutural plates small, triangular: sinus larger. Girdle with more solid scales, scarcely pilose, i ( >-.) Length 41, breadth .31 mill.; div. 90°.
Santa Barbara, O.///Vor///'/.
A. inh-rnexus CPR. MS., p. 3.
L. CERGl iii \MS Haddon. PI. 1, figs. 14-17.
Shell. — Minute, smooth, or with scattered minute tubercles ; the -idi- meet at an aii.irle of about 100°; sutural lamina' small, tri- anirular.
Anterior valve. — Small, smooth, with scattered aborted tubercles.
Int'Tinediate valves. — (V-ntral area smooth, with very faint longi- tudinal >tri;e; lateral areas scarcely discernible, with faint radial -tri:e and minute concentric interrupted ridges towards the apex, which pa>- into inconspicuous small scattered tubercles.
I1 sterior valve. — With full rounded umbo, behind which is a >hall«)\\ d< presHon. Anterior area : similar to the central areas of the intermediate valves. Posterior area similar to the anterior val-
(iiidlc. — Narrow, with delicate scales.
< '"lor. — rniform whitish.
. — Length 3, breadth !'."» mill.
< iills. — Posterior, « i-ht or nine in number (Haddon.}
Balfour Bay, Royal tfnun<l. Kerguelen, 60 fms. L. I:- r./nelensis HAD., Challenger Hep. xv, p. 12, t. 1, f. 3; t. *J. t. 3a-3e.
L. PAOl R8TB HER] rf.-li:-i. I'I. '2, figs. 39-40.
Shell . •l-shapfil, with the dorsal anirlc rounded;
red \\ith a tine, indistinct, irregular granulation, without dif-
LEPIDO] ]:;
entialed areas. Middle valves With fifaorl but higb lUtUIttl pl«
IK» insertion plate- ; sinus larj-e :IIH| deep ; tin- divi-i-.n of tl, mid lateral areas is marked in>ide l.\ :( .-.liirlit ._. .
margin «.r the anterior valve i< semicircular, MM- posterior mai
meeting ;il MII angle <'f l.'.n '. The po.-terior margin of the vnlvc is about tin- third of a circle, itfi In. nt 111:11 above a- a >traight line. The miicro is >nl.eenl ral, .-omewhat D t'orxvard than lichind.
Tlit' color ot'tlic valves is a pale irray-liniwn. irre-jularK witli brown dots which are lacking at the margins, l'-a\; a paler, unicoh.i-ed /(.no. The girdle is brownish, the scales white. The length cannot be given exactly, as all the >pecinien- \\ ••!••• strongly rolled up; but the maximum length seemed to l.e 1-7, breadth of the shell 2';") of the girdle O8 mill. (/;/fr.).
Leptochiton pagenstecheri PFFR., Jahrb. Hamburg. \Vi.--en- schat't lichen AnstaJten, iii Jahrgang, p. 107, t. 3, f. 3, 1 -
L. ASELLU8 Spongier. PI. 3, figs. 64, 65, 66.
Shell small, rather elevated, the dorsal ridge bluntly angular. Very minutely and evenly, but rather indistinctly, lirate-granulate; olive-ashen, often having longitudinal delicate pencilings of olive- green.
Anterior valve very densely, minutely and evenly granulated, the granules being irregularly, but usually visibly, arranged in radi- ating rows ; the peripheral third of the valve having coarse concen- tric wrinkles.
Intermediate valves have the central areas finely densely longi- tudinally granose-lirate. Lateral areas closely granose, the granules arranged in radiating rows on the lower portions, which are also wrinkled like the anterior and posterior valves. The lateral areas are separated from the central area by an inconspicuous low ridge.
Posterior valve with subcentral, rather low umbo, the posterior slope concave. Interior of valves white; sutural plates small.
Lofoten Is., Norway, Iceland and Greenland, *out/i to d'u/j »f Gascony.
Chiton asellus SIM:N<;I.I:R, Skriv. Nat. Solsk. 17(.»7, vol. iv. j.. — LOWE, Zool. Journ. ii, p. 101, t. 5, f. 3, 4, 1825. — BROWN: DESHAYES in LAMARCK An. s. Vert. ; MII>IH-:NI><>I:I i : FORBEB <$ 1 1. \\LEY, Brit. Moll. vol. ii, p. 407, t. f>!>, f. 1, '_'. — Chiton tiiiniinn.< ( 'IIKMNIT/; WOOD; DILI.WYN. — Chiton cinereu* MONTAGU;
14
: K'I.IVI : LoYEN; JEFFREYS, Brit. Conch, vol. iii, p. 218, v. p. 108, t. 56, f. •_' : I'. Z. S. 1882, p. 668., non LINNI:. teste II \\IIY. Ip-. Lin. Conch, p. 17. — Lepioehiton cinereus GRAY, P. 1*47. p. 127, !»;* • var. white, C. "'albus " exclus.) as type of genus. — J.fjitnrhitnu nuel/unli.&A. ADAMS, (Jen. i, )>. 473. — GRAY, Guide, p. 182.— Cn:. *•* p. 2.— BALL, I'roc. T. S. Nat. Mus. 1878, p. 318. — / Lein'il<']>!' unit cinereus L., SARS., Moll. Reg. Arct.Norv. p. ll'J. t. 7. f. *.— Chiton ittandicn* <iMi:i,., Syst. p. 3206. — C. fus- catus Li LOB, D(H l.n.wn. — C. scoticus LEAC-II, teste Jeffr. — C. onyx K. Skrivteraf Natnrhi.-torie-Selskabet (Udforlig Be Skri- velse over det mangeskallede Conchylie Slaegt af Linne kaldet ( hitun ined endeel nye Arter og Varietat) Oplaest, 28 Febr., 17!>4. iv. 1 Heft. P. «;•_', 17!»7 rf. Mai. HI. xvii, p. 113.
This >j>ccies is allied to L. granoliratus Cpr., but that is more
t« .1. the central and lateral areas are more diverse in sculpture,
and the concentric wrinkles are much stronger. In L. cancellnttt*
the lateral areas are raised, which is not the case with the asellus.
"Under the microscope this species can easily be separated from
;i. iixirginatus Jeffr.) by external characters. In the
nnon the scales are very minute, smooth, granular, reddish
and closely appressed to the girdle; in the Leptochiton they are
gravel like, irregularly crowded, larger, lengthened and striated. In
I, also, the valves are more beaked, especially in young
shells."
L. '.I:\NOI.H: \n > Carpenter, n. sp. PI. 2, figs. 47-53.
Shell oval, rather h»w and regularly convex, not angulated d<>r- sally. Very finely and closely granose-lirate, the anterior and pos- terior valves, and the lateral areas of the median valves strongly c.,rnii:ati-d c.mrrntrieally. Color "ashen-orange" or fleshy-ashen, with an ill-dHim-d darker dorsal stripe.
,nt«-rinr valve, ;md the lateral areas of the intermediate valves ,11. ly radially granose, and have a number of strong concentric wrink!«>. The central areas have close fine subgranose longitud- inal lira-. The lateral areas are slightly raised.
I'mho of the posterior valve somewhat in front of the middle, rather prominent ; posterior slope concave, radiately granose-lirate and strongly, irregularly, concentrically wrinkled.
LBPIDOP1 i ' 1:1 -. 10
(iirdle narrow, rl<»>rly hr.-et with delicate • '.
•oales,
LniLrth 10, hivadth 7 mill.; <li ver^enec l.'JQ0.
. M /.(•/•tni'lu'tun 1/rnnnfiriifiiit Cri:. MX. p. 3.
This speries may easily be distinguished from L. «/.w/i/
strniii: emieentrir wrinkles and the low, n.uiulcd arching of the
back.
L. CAJETANUS Poli. PL 2, figs. 41-46.
Shell oblong, elevated, solid. Valves regularly arched, the lateral areas very strongly raised, coarsely sculptured.
The median areas of the valves are sculptured with longitudinal lira?, which are gniiiulous and anastomose or branch irregularly. The head valve lias strong concentric ridges, 7 to 10 in number in adults, the intervals being finely pitted or granose. The lateral areas of the intermediate valves are very much raised, and sculp- tured with concentric ridges like the head valve. The posterior valve is very solid and thick, its apex posterior but recurved for- ward and much elevated; its posterior slope is subvertical, convex, terraced.
The sutural plates are triangular and stout; the jugal sinus rather narrow. Insertion plates are completely lacking. It is lusterless, and light buff in color.
Girdle very narrow and thin, bearing most minute, close delicate deciduous scales.
Length 23, breadth 12 mill.
Length 11, breadth 6£ mill.
Mediterranean and Adriatic Seas; Atlantic Ocean from Cape Breton to the Gulf of Gascony ; Canaries ; Pliocene of Biot (Mar- itime Alps'), of Calabria and Modenais; Pleistocene of Monte Pellegrino.
Ch. cajetanus POLI, Test. utr. Sicil., i, t. 4, f. 1, 2, 1791.— Pin i.. Enum. Moll. Sicil. i, p. 108, ii, p. 83. — WEINKAUFF, Conch, des Mittelm, ii, p. 412. — REEVE, Conch, Icon. f. 171. — Lepidopl> cayetanus Poli, Risso, Hist. Eur. Merid. iv, p. 267. — Ch. cult" Poli, JEFFR., P. Z. S. 1882, p. QQ7.—Leptochiton cuj'.'tnnu* Poli, CPR. mss. p. 7. — Holochiton cajetanus Poli, BUQUOY, DAUT/I \ i and DOLLFUS, Moll. Mar. Roussillou, i, p. 500, t. 61, f. 1-3 ; i f. 5.
16 LEPIDOPLEUBU8,
In -culpture tliis sp -trikinirly different from the other
and in fact from all other Chitons. The lateral areas
ami front \:il , -1, the latter being compared by
ater to a circular flight <»f nmndcd >irps.
The Atlantic >p, cinieii^ arc always larger than those from the . the measurement* Jird given above being taken from an Ocean example, the second measurements from an Italian speci- men.
It i- the i llisso's genii- Lepidopleurui.
;ion Deshayesiff/'t Carpenter, 1878.
Deshayesiei/'i CAKI-IMKR mss., p. 10. — DALL, Proc. I . S. Nat. ;.. :I14; l.<: 1882, p. 286.— HADDON, 'Challenger' IV.lyplacophora, p. 9.
Shdl ehm-ated: valves curved, somewhat beaked; umbo flat- tened: m> insertion plates ; sutural plates, triangular ; girdle spicu- lose.
Ditli-i> from L<i>tochiton not only in its hairy girdle but al>o in ':itt«-m-d iimlio and its valves, which are somewhat thrown for- um d, forming a decided transition toward some of the palaeozoic forms.
L. . i KV kTOH Carpenter, n. sp. PL 4, figs. 78,79, 80, 81.
Shell rather elongated, whitish-ashen, planate ; dorsal ridge rounded ; umho central, flat; valves with pointed apices, all curved ; the interior .if the posterior part of each valve much scooped out. Jugal area broadly V-shaped, </m/x/ reticulated, the lines of pus- tules parallel in the middle, diverging at the sides, interstices pnnc- ( 'ei.tral areas with longitudinal distant, beaded lines, 8 to 10 ach side, tt -ndinur toward the juguin forward, interstices decus- al areas somewhat swollen, expanded, but scarcely • •d by a line from the central areas; coarsely, irregularly gran- oee, and concentrically waved.
lu-ide: insertion plates absent, the position of them flat: sinus l.r-.a.l. t'..ll«»wiiiLr the curvature of the valve.
<iirdlr delicate, clothed with small scattered spines, occasionally larger, and chafi'y lealat. (Cjpr.)
Length 1 1, l.readtl. 15.1 mill.; div. 120°.
./'tjnin (A. Adams).
II.\M.I:V\. 17
(Detkayesiella) curvatut < 'pr.. DAI.I,. IY<>r. I
N:i1. Mil-.. 1*7*. p. •"•IMname ami -jeiier'n- e!
Dtthayetiella curvata c/ir. ,l/.sf. p. lo.
This shell externally looks very niiieh like an . I "//,//, o'7, /'/<,// without the pore hunches, of \\hieh there i< no trace. The plam d oil' parts inside the apices are unusually large. (Q>r.)
Genus II. IIANLKYA Gray, 1857,
Hanfcya GBAY, Guide Syst. Di>t. Moll. P.. M., p. 186, type"//. debilis Gray— Chiton h«n/<-i/i Thorpe." — Hnn.leyia DAM., and Il<n,- lei<t of (1ARri:vn.i:, J/N.
Anterior valve having an insertion plate without slits, but rough- ened ; intermediate and posterior valves having no insertion ph eaves small; girdle with iine spines ; no girdle pores.
This genus differs from Leptochifon and Dethayesiella in ing an insertion plate upon the anterior valve. It differs from Hemiarthrum and Mlcroplax in having no insertion plates upon the intermediate and posterior valves, and in lacking girdle pores.
In Dr. Gray's original generic diagnosis, the girdle is said to have pores furnished with tufts of bristles. This has proved to be an error, the statement evidently having been based upon a speci- men in which the girdle was transversely wrinkled, throwing the bristles into close groups.
H. HANLEYI Bean. PI. 3, figs. 71-79.
Shell oblong, convex, the lateral slopes nearly straight, the dorsal ridge rather angular. Sculpture consisting of numerous rounded tubercles, arranged in longitudinal rows on the central areas, the series of tubercles finer and closer upon the jugum ; head plate and lateral areas having coarser rather irregular tubercles. The lateral areas are not raised. The mucro is median, rather elevated.
The plates of insertion of posterior and intermediate valves are obsolete, edges roughened ; anterior valve having a short, acute insertion plate, outwardly rugose-sulcate, the sulci indenting, but scarcely slitting the margin. Sutural plates moderate; sinus v«-ry wide, denticulated by the sculpture of the outside. Eaves vei y small.
Girdle narrow, beset with numerous short and longer horn-col- ored spicules. Length 10, breadth 5 mill., sometimes larger. 2
IIAM.KYA.
British seas iiorfhn-" v ^f<^f/eroe, near North Cape,
1 fms. ; Stdlwdrjeti Hunk, Massachusetts Bay, in 38 /MS. Chiton h>t/tl suppl. to Thorpe's Brit. Mar. Conch, p. _
and HAM. KY. Hist. P.rit. Moll, ii, p. 398, t.
.-.lini:.. IJrit. Condi, iii, p. 215; v, p. 198, t. 55, f. s.—
5, Moll. ] . Norv. p. 109, t. 7, f. 5. — Hanleia hanleyi
P.. an, Cri:. mss. p. 8. — llanleiia dcbilis GRAY, Guide, p. 186, ]x~>7.
// , •";/,/ dclUls Cray, DAI.I.. PrOC. I". 8, Nat. Mns. 1*7*, p. 319.
•"//(//• LUVKN, Ind. Moll., p. I'll.
This spi-cii's has been reporti-d tVoin Palermo by Monterosato '.!o,,r. dr Conch. 1878, p. 147).
Yar. LBY88ORUM M. Sars. PI. 4, figs. 74, 75, 7d, 77.
Closely allied to //. h'tiJciii, but more than double the size, hav- ing thr -mile \vidor and thicker, spicules shorter; shell narrower, with !«•>> distinct sculpture. Pale brown, the girdle flesh-brown. jth :;t mill. fS.trs.')
Bergen, Xorway, 150-200 fms.
Ch. abyssoruiii >F. Sars, G. O. SARS, Moll. Reg. Arct. Norv. p. . t. 7, f. 4; t. 34, f. 3.
H. MI:M.I« -AIIIA Mi-hels vV Adams. PL 4, figs. 82, 83, 84, 85.
Shell oblong-oval, not much elevated, dorsal ridge obtuse, lateral
elopes flattened ; ashen-white, the entire surface granulated, gran-
!y crowded, forming longitudinal series, about 20 on each
>id«-: lateral areas ha idly defined, irregularly granulated, the granules
larger. .luirum scarcely defined, broadly vaulted. Mucro low or
: al.
Interior having a solid, rather acute, but scarcely fissured inser- tion plate to the anterior valve ; none upon the central and posterior valve.-. Sutiiral plates lariro, subtriangular ; sinus simple, wide, scarcely laminate. Kaves wide. Girdle wide, solid, leathery, finely Spiculate, the spicules glassy, here and there crowded; no p
< Jills posterior, about \~> on each side.
•i_rth 1 "», hr.-adtli 85 mill.; divergence 123°. Length 1th 15 mill.; divergence 108°. (Q?r.)
Casco B<i>,, r<n-t/>nnl llarhur <ind Grand MuiKtn, M '»
If, A A.. Bo«t. .lourn. N. II. iv, p. 42, t, 4, f.
8, 1> -I. i., Inv.-rt. of Ma.s.. P.inney's Edit, p. 2(>3, f. 526.—
M .. ii.. -1 1:1 ••!••]:., P. /. S. 1882?
IM.MI MM IIIMM. Hi
j>. <5H7.- • Hanky ia mtndicaria CPU., N. Km:. Oiitim.--, Ann. I
N. II.- I: xiii, ',,. iL'l ; .J/X., ,,.!), 10.— DAI. I,, PrOC, I tfuB.
1878, p. 319.
H. TROPICALffi Dull. PI. 6, figs. 12-18.
Chiton about !<)•() nun. in K-n^tli and .">•() nun. in width, with the usual characters of the genus, i. e., anterior valve with an un-lit insertion plate, other valves without even the plates; hack with an angle of about 90°. Girdle (fig. 13) in the dried specimens, thin, narrow, covered with close-set, white, glassy, slender spine- • 1-n I -."> nun. in length) above, and below with similar but much shorter ones. Anterior valve with a well-marked mucro, from which proceed concentric striae of growth, and in front of which the valve is a little concave ; sculpture of little less tesselated flattened nodules radiating from the mucro, above which are irregularly distributed small, opaque, white pustular bubbles of shelly matter looking like attached grains of coral sand ; posterior valve smaller, flatter, with similar sculpture, but the pustules take on a decidedly cylindrical shape and are elongated, looking like the stalks of decapitated mushrooms; this arrangement is still more marked on the posterior lateral areas of the intermediate valves, the anterior lateral areas also exhibit (less prominently), but with an obliquely anteropos- terior radiation, while the former have it more entirely lateral from the mucrones ; dorsal areas with the tesselated sculpture alone, arranged longitudinally. Color entirely white.
Sand Key, Florida, in 128 fms.
Hanleyia tropicalis DALL, Bull. Mus. Comp. Zool. ix, p. 53, 1881 ; < Blake' Gastrop. p. 415, t. 26, f. 8c, 8d ; Bull. U. S. Nat. Mus. No. 37, p. 172, t. 26, f. 8c, 8d.
Genus III. HEMIARTHRUM Carpenter, 1876.
Hemiarthrum CPR., in Dall's Moll, of Kerguelen I., Bull. U. S. Nat. Mus. ii, 1876, p. 44.
Head and tail valves having smooth, unslit insertion plates, the intermediate plates lacking them. Eaves minute. Sinus broad and spongy. Girdle solid, downy, poriferous, the lateral tufts small. Gills short.
Differs from all the preceding genera in having both head and tail valves provided with insertion plates, and in the poriferous girdle.
20 HEMIARTH1MM.
II. BBTULOSUH Carpenter. PL 5, figs. 89-100; 1-8.
The color of the shell is a uniform warm dark brown, and the girdle is chestnut brown, with a pale crenulated border round the margin of tin- valves. In each of the dark triangular bays between tin- valve- i- a .-mail tuft of short white spicular scales, and there are imilar tufts round the anterior border of the first valve. The anterior and po>trrior valves and the lateral areas of the inter- mediate valves are marked by concentric lines of growth, otherwise the latter are scarcely discernible. The jugum is very gently rounded, so that the pleura are slightly depressed. The unslit in- sertion plate of the anterior and posterior valves is shown in figs. 90, 94, and 4. ~>, (\. The girdle (fig. 98) is thick and soft, with a minute scattered scales. There is a distinct fringe of reddish brown elongated striated scales round the margin. The scales forming the tufts are stout, and white in color. Carpenter describes the anterior tufts as about four in number; in my specimen there are -i\ anterior tufts. Evidently Carpenter was not quite satisfied on this point, as in all other Chitons which possess tufts, only four are p resent; and, consequently, that number might be expected to occur in this species also. The head lappets are rather large, and the anus is on a large rounded papilla. The longitudinal band on the under side of the girdle (veil of Carpenter) is produced into flaps at the po.-terior extremity.
Tin- Lrill> rjil. .">, figs. 1, 99, 100, 7), form a short posterior row, and appear to be about six in number; they decrease in size anttr- iorly.
Length '.) mm. ; breadth 4 mm. ; side of valves meet at an angle of about 115°. (Haddon.)
Length i:1,, width 7 mill. (Q?r.)
Kerguelen Island, on stones at low water (Kidder); and Royal Sound on shore (' Challenger ') ; South Georgia (Pffr).
Hemi'irthrum setn/nsnm CARPENTER 1/&, p. 13. — DALL, Bull. U.
it. Mus. ii, l>7'i. p. 44.— HADDON,' Challenger 'Poly placophora, p. 11. t. 1. f. 1 : t. L'. i'. 4a-l. — MAI.-TKNS and PFKI -FKK, Jahrb. der llambnrgischen Wissenschaftlichen Austalten iii, p. ]08, t. .'), f. 4, 1886,
The specimens from S. Georgia were much eroded ; they meas- : about s-ll mill., and were when alive, ''brown-black almost blaek. " One of these is figured on pi. 5, figs. 1, 2, 3.
MI< HOI-LAX. LM
This shell, externally, resembles <ome n\' the ooane, ill-defined Aranthochitons. The girdle, however, is narrower ;m«l Muooth<-r than in that -jenus, and the pores so extremely minute that in a dry specimen they would escape attention. Within, however, the features are entirely new though not unexpected. It forms a tran- sition between Hanleya (mendicaria) and the articulate chitons. A single unslit lamina surrounds both the terminal valves, projecting far beyond the external layer. In the posterior plate this is con- tinued forward to form part of the sutural laminie. These in all the valves slope off both toward the middle and toward the sides, so as to take the place of the ordinary side-lamina3, which here do not exist.
Genus IV. MICROPLAX Adams & Angas, 1864.
Microplax H. AD. & ANG., Proc. Zool. Soc. 1864, p. 194, type M. gniyi Ad. & Ang. — CARPENTER MS., p. 12.
Insertion plates smooth and thin, present in all the valves. Sut- ural plates obsolete, the sinus extremely shallow. Girdle thin, horny, most minutely granulous. Valves largely concealed in the girdle, the exposed portions small and separated.
In the present genus a small portion only of each valve is exposed ; and the sutural plates and sinus are obsolete. No other Chiton having unslit insertion plates approaches this remarkable group.
M. GRAYI Adams and Angas. PI. 6, figs. 9, 10, 11.
Shell elongated, convex, brown ; exposed portion of the valves minute, wide heart-shaped, carinated, strongly granulated, the inter- vals between the exposed parts of the valves about as long as the latter. Lateral areas defined by a distinct rib. Girdle moderate, corneous, smooth (A. and ^4). Length 13, width 5 mill.
Sydney Harbor, Australia, under stones at low water.
Microplax grayi H. AD. and ANG., P. Z. S. 1864, p. 194, /. c. 1865, p. 58, t. 11, f. 16.— ANGAS, P. Z. S. 1867, p. 224.— CARPEN- TER MS., p. 12.
The figures given were drawn by Mr. E. A. Smith from the type specimen.
Carpenter's notes upon the unique specimen in coll. H. Adams are as follows: It is 'quite transparent, looking like thin horn. There are very slight overlappings of the valves, corresponding to
22
the sutural lamina-, hut no slits at all are to be seen. The lamina? are very square. n..t wavy as in the other covered species. There is a very slight indication of riblets or strife continuing from the • nal rili do\\ n to the edge of the lamina, but I cannot see the least indication of nicks or lobes at the edge. The sutural lamina- are extremely slight, projecting over each other about to the line of the mucro, with the very -li-lite-t sinus in the middle between them.
The front valve is horse-shoe shaped, with flat base, mucro a little removed from the margin. It is nearly smooth at the mucro, becoming gradually more granulose. The whole color is a greenish pink.
The intermediate valves all point forward; their mucrones in no case touch the posterior edges ; two smooth, diagonal ribs, curved forwards, separate the lateral and central areas, both of which are jr ran u lose.
The posterior valve has the mucro a little anterior, the two oblique ribs curving backwards.
It will be noted that the umbo or mucro in the posterior valve is directed forward, whilst in the other valves it is, as usual, directed 1 »ack wards.
The divergence is 76°, very elevated. The exposed part of the valves measure about 1J X If mill. The girdle is everywhere minutely granular — too minutely to be shown in the illustration.
I'a.nily CHITONIDJS,
— Ischnoidea -j- Lop/ii/rnidcn -, AoaniAoufoaof CARPBVTEB. /
n<r/i,'t<»ii<l<r, Lu^hijritli- and Arnnffinji/cnridir I).\l,i., lilal
poda, p. -11"), IK!. -Lophyochitonidcc, Chcetochiionida and
('hftoiu'ilir K<>< in r.iMM,, Miss. Sci. du ( 'aj> Horn, vi, /ool., j.. ' 1 :; I
l-l.",, L889.— CA&m L., FISCHER, Manual, p. 879.
Chitons in which all of the valves pOMeta insertion-plates -lit into teeth; the insertion-plate of the tail valve similar to that of the head valve. Eaves developed.
The conclusion has been forced upon me that the- three divisions B, Ischnoidea, C, Lophyroidea, D, Acanthoidea of Carpenter's arrangement cannot be separated by sufficiently definite characters to give them the rank of families. The Ischnoidea blend with the Lophyroidea through certain species of Chcetopleura, Tonicella and Tonicia ; and the connection with those Acanthoidea having Isch- noid insertion plates is even closer. It is by no means certain that the Acanthoidea constitute a natural group; the portion having pectinated insertion plates may prove more closely allied to the true Chitons (Lophyroidea), whilst those with sharp, smooth inser- tion plates would hold a like relation to the Ischnoidea. It is, in fact, not an easy matter to decide whether such genera as Callisto- chiton and Pallochiton belong to the Ischnoid or the Acanthoid series, Carpenter referring them to the former, whilst my own stud- ies cause me to place them in the last named group.
In the present work I have concluded to recognize Carpenter's three divisions as subfamilies, believing it better to retain a classifi- cation admitted to be faulty than to institute radical changes which I am at present unable to place upon an indisputable basis. The regular Chitons having slit insertion plates may therefore be divided into the following three
Subfamilies :
Subfamily ISCHNOCHITONIN^E. Insertion plates smooth or nearly so, sharp, slit into teeth, which project outward on all of the valves.
Subfamily CHITONINJE. Insertion plates finely pectinated, blunt- edged, the teeth all projecting outward.
Subfamily ACAXTHOPLEURIN^E. Insertion plates smooth and acute, or pectinated and obtuse ; teeth of the posterior valve dis- tinctly directed forward, not outward.
(23)
24
Subfamily ISCHNOCHITONIN^E.
Ischnoidea CPR., Table of Regular Chitons, and DALL, Proc. I. at. Mus. l*si>. p. 283, (in 'part; < Jenera 19-24 excluded).— hchruH-hitonnlt DALL, ' Blake ' (iastmp. p. 4M, 1889.
I have above given some of the reasons which induce me to con- sider this group as a subfamily rather than a family. I am wholly disposed to believe that the subfamily as here constituted, is rather artificial ; and some of the genera may require consolidation. The relation existing between Cluztopleura and Tonicia especially calls tor investigation ; and there are some forms (section Cyanoplax) which seem to bridge the gap between Chcetopleura and Tonicella.
Synopsis of Genera of Ischnochitonince. Genus V. LEPTOPLAX Cpr.
Valves thin, partly immersed in the thin smooth girdle; insertion plates acute, having jew slits. Umbo of posterior valve median.
Genus VI. SPOXGIOCHITON Cpr.
Valves partly Immersed. Insertion plates acute; umbo of pos- terior valve median. Girdle spongy, having chaffy scales and hair- lets, and produced forward.
Genus VII. CH^ETOPLEUPvA Shutthv.
Valves exposed; insertion plates smoother obsoletely grooved :<le; eaves solid; umbo of posterior valve central or anterior. Girdle leathery, more or less hair//.
Genus VIII. TONICELLA Cpr.
Valves exposed ; insertion plates smooth or slightly grooved out- side; eaves spongy; umbo of posterior valve anterior. Girdle leathery and smooth, without scales or hairs.
Genus IX. SCHIZOPLAX Dall.
Valves exposed, and similar to those of Tonicella except that the intermediate valves have ^.median longitudinal *M filled with cartil- age. Eaves very sponyij. ( iirdle leathery, as in Tonicella.
LBFTOPLAX, 25
Gem.> X. CALLOCIIIToN
Valves rxp<>srd : insertion plates cut into num< ill rising
from very *IHHHJ\J COVCS, the teeth more or les~ /mftressed at tin- out-
side edges. Sutural-platet continuous acron the vr,r>/ nhullmr m*',/;,/,, x/;//(.<. <;irdle typically covered with fine eompaet diamond -haped scales : hut iii the suhgnms Stereochiton sparsely downv, fV«-«jinMit.Iv naked l»y erosion.
Genus XI, ISCHNOCHITON Gray.
Valves exposed ; insertion phites sharp, smooth ; eaves not spongy, or rarely so. Umbo of posterior valve varying from pos- terior to anterior. Girdle covered with imbricating scales.
Genus V. LEPTOPLAX Carpenter, 1882.
Leptoplax CPR. MS., and Table of Regular Chitons, 1871. — DA i.i.. Proc. U. S. Nat. Mus. 1882, p. 286. Type C. codrctatus Sby.
Valves thin, partly immersed in the thin, smooth girdle. Inser- tion plates acute, with few slits, but regular. Sinus scarcely toothed ; mucro median. (Q?r.)
The prominent characters of this genus are, (1) valves partly covered by a thin extension of the girdle, (2) girdle smooth, as in Tonicella, (3) insertion plates long, with few slits. The gills are unknown.
L. COARCTATUS Sowerby. PL 11, figs. 38, 39.
Shell elongated, very delicate, little elevated, the dorsal ridge acute ; greenish-ashen or reddish-olive. Valves of the normal form, but two-thirds covered by a thin cuticle continued from the girdle. Exposed portion of the valves flask-shaped, the jugular area smooth, subelevated, having longitudinal rows of points; central areas and end valves having large pustules, close and somewhat radiately placed, about 20 on each side in a young specimen, 100 in an adult : lateral areas scarcely defined ; mucro slightly behind the center, rather elevated. Interior: Plates of insertion very long, tinted, here and there delicately striated outside. Slits small, in the posterior valve 6, posteriorly situated; central valves 1, anterior valves 4, having shallow grooves running up to the cave-. Sinus
26 SPONGIOCHITOX.
moderate, indented by the sculpture of the outside. Girdle very thin, ratlin- expanded, smooth. (Cpr.)
Length 131, breadth 71 mill.; divergence 120°.
Island of Bohol, Philippines-
Chiton eoarctatut SOWKKHV. 1*. /. S. 1841, p. 62. — REEVE, Conch. Icon., t. 20, f. 127. — Leptoplax conrdatus CPR. MS., and Lept. rubrotinrt'i ( JpR. -VX. <>/hn.
This mi.irht he regarded as an extremely -delicate Katheriua, but that the valves are thrown forward and the tail-plate is Ischnochitonoid rather than Mopaloid. It differs from Fannia as Ischnochiton does from Chiton, in the extreme thinness and general smoothness of the sharp teeth and in the non-dentition of the sinus. I have seen no other regular Chiton in which the insertion plates are tinted, the head valve having only four slits, and the tail valve with so long a lamina, unh'ssured, at the anterior sides. (Cjpr.)
Carpenter at first described this form under the name rubrotincta but he discovered its identity with C. coarctatus by an examination of the type of the latter. The sculpture varies much ; sometimes there are a few large grains, sometimes many smaller ones.
Genus VI. SPONGIOCHITON Carpenter.
Spongiochiton CPR., Table of Regular Chitons, 1873. — DALL, Proc. U. S. Nat. Mus. 1882, p. 272, 283, 286, 289, 290.
Valves partly immersed ; insertion plates acute, Ischnoid ; sinus large, smooth ; raucro median, flat ; girdle spongy, produced forward.
S. PRODUCTUS Carpenter, n. sp.
Shell oval, the valves immersed two-fifths of their width ; exposed portion rubicund, flat, the jugum arcuate, paler. Lateral areas scarcely defined. Entire surface sculptured with prominent pebbles, worn at the jugum. Mucro submedian, flat.
Interior : posterior valve with 6, central valve 1, anterior valve 5 slits; teeth long, acute, scarcely serrate; sinus wide, smooth, extremely deep. Eaves narrow, scarcely grooved.
Girdle produced in front, spongy, sparsely covered with chaffy scales and translucent hairlets.
Length 25, breadth 161 mill. ; divergence 130°. (Q>r.)
New Zealand (Mus. Cum. no. 50).
( ill TOPLS1 i: \. -7
This very peculiar shell rescmUes .Mopalia Mainvillei in mantle and inner.); and Nuttallina in tin- l«»n.Lr, Mnooth plate.-, -eparaN d l.y a d.-ep, not laminated sinn<. Tin- side slils how, and
deep instead of duplicate and angular, as in thai rior plates are not tin-own forward nor waved as in Mopalia. I^av- \i\^ out of view the anterior prolongation of the mantle, which \» a variable character even anioni: Mopalia, it may be regarded as a partially covered Tonicella. The slits are abnormally few, as in Leptoplax. But for the characters of the tail plate I should have considered it intermediate between Mopalia and Katherina. (<
Genus VII. CH^TOPLEURA Shuttleworth, l*f>3.
Chcctopleura SHUTTLW., Diagn. neuer Moll. no. 4, iiber den Ban der Chitoniden, etc., in Bern. Mittheil. p. 66, June, 18~>3 (~ Acan- thopleuraGray, ex parte). — Choetopleura CPR. MS. and DALL, 1'roc. U. S. Nat. Mus. 1878, p. 329, type C. peruviana Lam. — Acantko- pleura, GRAY, Guide Moll. B. M. p. 183.
Valves as in Ischnochiton ; eaves solid ; girdle leathery, more or less hairy ; gills extending almost or entirely to the front end of the foot.
The present group seems to me to stand naturally on the confines of the Ischnochitonoid series, having decided relations to the true Chitons and especially to Tonicia.
Carpenter made a subgenus, Maugerella, under Chcetoplcura, for a Radsioid Californian form, which I have excluded from the genus, as its affinities are with the Radsioid Ischnochitons. The following able discussion of this genus is from Carpenter's MS. :
Shuttleworth, in distinguishing this genus from Acanthopleura by the mantle characters only, does not seem to have observed the co- ordinate differences in the hind valve and the insertion plates. Messrs Adams united to this genus Eudoxochiton and Craspedo- chiton which do not belong to the same section. Gray, in his " Guide," p. 183, ignores the genera of Shuttleworth, but preserves the distinction between Chsetopleura and Acanthopleura. Most unfortunately, however, he chooses to keep the name Acanthopleura for Chsetopleura of Shuttleworth and Add., and makes a fresh name Maugeria for the restricted Acanthopleura of Shuttleworth and Add. Even if Shuttleworth had been unwise in his mode of division, he would have been entitled to precedence ; but fortunately he kept Acanthopleura for the first section of Guilding's group,
28 < II.V.KTI.Kt i: \.
.Jouni. v, p. 28, represented by Chiton spin osus 8by, The
• Indian -pecies belongini: to this section (A. picea) must have been familiar to him and u'iven ri>e to the " /<ma crassa carnosa" of h;> diairno>i>. with which < 'iKctoj.leura does not accord. The -•ntcd l»v < '. peruvianus 1'onns only tlie sixtli among seven sections into which Guilding divided his genus.
Bhottleworth and Adams place the hairy chitons, in Chsetopleura
and those with shelly l>ristle> in Acanthopleiira.
The distinction is obvious as between peruviana and picea, but not so in t lie cast' of many -pecies \\lien the bristles are corneous but With more or len of shelly matter in their substance. There are also ma; | in which the hairs are shortened and flattened
into chaffy scales and others in which hairs grow irregularly in the midst of a spongy or chaffy mass. Gray, moreover, assigns "shelly t-» the peruviana group and " shelly spines or bristles " to tin- picea jrroup. Tothefir-t. however, are assigned thin, to the second thick valves. Both are described as having the insertion plate- pectinated ; but as being " regular well developed " in peru- viana, hut "narrow, rather irregular " in picea. This last results from what seem- to me the essential difference. Acanthopleiira is hunch-hacked on the tail plate, with the insertion plates thrown for- ; and L'r-'ovcil outside ; while Chretopleura has the normal tail plate of Chiton and Ischnochiton and agrees with the latter genus in having the insertion plates not pectinated and nearly smooth. The transition forms from the densely pilose peruviana to the smooth mantle of Tonicella are so gradual that the latter might rank as a subgenus under Chsetopleura were it not that the gills in tin- ircmis are represented as elongate. (Cpr.)
< 'h;etopleura should be compared with the Lophyroid genus Ton- icia, which has similar ambient gills and solid eaves, and frequently has th- t--r i h scarcely more pectinated than in the larger Chieto- plcuras.
The genus consists of several groups of species. (1) Typical ;h«-r large, and having very delicate sculpture; and (2) Group of C.gemmea, having the lateral areas strongly raised and coarsely sculptured, the central areas also sculptured.
(1). Urniij, of C.
n \I\N\ Lamarck, IM. rj, ii^. 42-46.
• •ssed, dull a.-h colored, the girdle clothed with long, Stifi*. crUp black hair, a fringe of which also projects from each
' : 'i .1 i i: \.
suture. The valves MIT iniiiiitclv .-culpmred \vitli very minute granules in lin»-> which diverge -li-htly at the jiiiriini, more upon tin1 >ide- ol' the central area-, divaricate on tlie horder ln-t central and lateral areas, and an- radiating upon the liiti-ral ai and tenninal valves. The iimho of the tail valve i> low, -omeuhal anterior.
Interior white with a brown stain at the back edire of each valv«-. Anterior valve having lon^- insertion plates which are di.-tinctlv crennlated outside, ami have !)-!() slits, central valves with 1 -lit, post, valve with 7~V slits. Sutural plates very broad, connected across the sinus hy a narrow plate; eaves narrow, .-hort,
Length 38, breadth 20 mill.
Lima, Peru; Chili; to Oij>r
Chiton periivianus LMK., An. s. Vert, vi, p. 321 ; ed. Dh., vii, p. 491. — Barnes, Amer. Jour. Sci. vii, p. 10, t. 3, f. 2. — SOWB., Conch. Illustr. f. 44. — KI:I:\ i: Conch. Icon. f. 50. — Chaetopleura peruviana Lm., SHUTTLW., Diagn. n. Moll. nr. 4, p. 07.— \{<>< \\ i.m; ., Moll. Cap Horn, p. 1-^). — Acanthopleura peruviana Lm., TAP. CAN., Viag. Magenta, p. 77.
This form is readily known by its girdle covering and sutural fringes of long black hairs. The sutural plates are strongly devel- oped, slightly recalling Leptoplax. The hair is crisp and coarse, like that of a horse's tail. The gills extend forward to the head.
C. HENNAHI Gray. PI. 12, figs. 47, 48, 49 ; pi. 17, fig. 39.
Shell oval, rather depressed, dorsal ridge obtuse, side slopes nearly straight. Color variable, but generally either reddish-brown marked with red, or greenish-white marked with brown ; surface smooth to the naked eye. Girdle leathery, covered with short hairs, which may readily be rubbed off.
The median valves are about four times as wide as long; the lateral areas are only weakly indicated ; the tail valve is depre>- d, with the slightly prominent umbo in front of the middle, the pos- terior slope concave. The sculpture consists of closely beaded ti in- separated threads, which are longitudinal on the central, radiating on the lateral areas and end valves ; under this may be seen an excessively fine, close shagreening of the whole surface.
Inside white, each valve marked with brown under the beaks. Sutural plates of equal width from the outer angle of the valve to the rather shallow sinus. Ant. valve having 13, central valves 1. po>t.
30 CEJSTOPLBURA.
valve !•"> >lits, (i 'arpenter Liives : ant. v. 10, centr. 1, post. 9-12 slits). Teeth sharp, those of the head valve prominently grooved outside. Eaves narrow and short, grooved just above the teeth, not spongy.
Girdle .pi. 17, fig. 39) granulated, sparsely clothed with stiff white spinelet-.
( Jills continuous to the head, as in C. pernviana.
\, Qgth 13, l-readth 28 mill.
Callao Peru, on Pectens, in 5-7 fms-
Ch. henwihi <JKAY Spiril. Zool. p. 6, July, 1828. — SOWB., Conch. Illustr. t'. 1, 3:>.— RKKVI:. ( ouch. Icon. t. 7, f. 37, and pi. 23, lower mitral lLrure.
This >pecies is closely allied to C. peruviana in form of the
valves and sculpture. The girdle hairs are short, deciduous, and
when retained they are disposed to lie in bunches. The front
teeth are decidedly grooved outside, in old specimens resembling
lafulva.
i. ii i- Reeve. PI. 14, fig. 80.
Shell ovate, smooth or very closely marked throughout with minute raised dots ; lateral areas faintly radiately grooved. Red- dish chocolate-brown, unspotted ; ligament horny, beset with very short, hard bristles (Rve.)
Habitat unknown.
f'hHon »<>!>;iis "Gray," REEVE, Conch. Icon. t. 21, f. 139, May, 1847. Not Chiton nobilis Gray. — Chcetopleura nobilis Rv., CPR.
m
Carpenter further describes the type specimen: mucro median little elevated : valves rounded at the sides. Interior: post, valve with J), ant. 11, centr. 1 slit. Teeth acute; eaves small; sinus small, deep, planate, smooth. Girdle leathery, pale brown, sparsely and irre<rular]y I.CM-I with very short, solid, black, somewhat scale- like bristles.
The above is written from the type specimen which Rve. described as the C. nobilis of Cray, and which Mr. Adams most kindly sub- mitted to my examination. This shell proves to be a normal ( 'lueto- .i : while Knnoxochiton nobilis Gray, belongs to the Lophy- roid section. Lest the confusion should be repeated, the following notes on the sculpture of C. nobilis Rve. may be useful.
i 1 1. r.i <>r i i.i i: \. :;i
(Vntral area- having sul.parallel or slightly radiating lin- granules, about L'U on cadi side. Lateral area- -eareely «|eline<|, having about 1<> irregular radiating line-, tin- ant. va! post, valve 40 such lines. Kntiiv siirlaee nio-t niiniitely pun.
This species must not l)e mistaken for the e.r/crn<i/ii/ verv -imilar
Eudozochiton.
(2) Group of C. gemmea.
( . I.I:MMI-:A Carpenter, n. sp. PI. 13, figs. 69-74.
Shell oblong, elevated, red, olive-ashen or yellow; umlm of tail valve depressed, situated behind the middle. Lateral areas decidedly raised, coarsely radiately tuberculate; central areas having longi- tudinal beaded line. Girdle narrow, leathery, sparsely clothed with short hyaline hairs, which are readily rubbed off.
The valves are elevated. The central areas are sculptured with elevated, distinctly beaded longitudinal cords, about 15 in number on each side ; they became very small or subobsolete upon the jugum. The lateral areas are strongly differentiated ; they have 5 to 7 radiating rows of distinct, clear-cut tubercles. The mucro does not rise above the general level of the posterior valve.
Inside often tinted with red, often having a red or black spot at the jugal sinus. Sutural plates well-rounded, the sinus rather deep and angular. Anterior valve having 9-12, median 1, posterior valve 7-8 slits. Teeth rather blunt and stout ; eaves not spongy, rather wide.
Length 16?, breadth 8 mill.
Monterey, California.
Chastopleura gemmea CPU. MS.
This beautiful little species is excessively similar to Ischnochiton mertensii in sculpture, but the smaller size, narrower form, and especially the short, transparent hairs of the girdle, distinguish it.
C. BULLATA Carpenter.
Shell subovate, elevated, olivaceous; intermediate valves ornamented with strong rows of pustules ; lateral areas very narrow, tubercu- late, sometimes pustulate. Central areas having lines of tubercles, about 7 on each side, and perpendicular lines, interstices granulated. End valves having about 11 radiating rows of pustules; mucro somewhat conspicuous. Girdle wide, having small hairlets. Sutural
32 OttBIOPLEURA. ,
plates triaiiLMilatc : sinus deep; margins of the valves simple, the median having 1, the terminal valves about 7 slits. (£)>?'•) ill, :;. alt. , mill; divergence 110°.
if/an, on Spondylus calcil'er.
Lepidopleurus bntlaliis Cri:., Ma/at. Catal. p. 195. — Chtttojil* lnll» ' !/>'.— L. hnll'itu* i'"r. (•<>/<• Iferus CPR., 1. c. p. 196.
One fresh specimen (><>me\vliat crushed in extraction) and a few perfe i were found of this species, which is characterized by
the very >t mil-: row <>f tubercles, (like pebbles) which lie on the diagonal line; by the rows of somewhat strong tubercles on the central area, rmminir perpendicularly from the diagonal towards the juguni and the granules over the whole surface, somewhat corru- gated on the juguni. The internal plates of all the valves have an :ial projection from the outer surface, as in L. .«ni<juJuem.
Carpenter describes a larger specimen in ms. as follows : Mucro median, -eaively elevated. Vermilion and olive, very irregularly, vividly maculated. Interior: posterior valve with 9, central valves 1, anterior valve 11 slits. Teeth acute. Eaves projecting, pectin- ated by the sculpture. Sinus moderate, high, laminate. Girdle smooth, ornamented with sparse hairlets. Gills subambient, scarcely reaehiiiLT the head. Abedhas Reefs. (Mus. Yale College). This specimen is about 15 mill, long, 6i broad, divergence 125°. It agrees in most respects with the very young shell described in Maz. ( 'atal., but is much longer in proportion.
Yai. C \i.< ii I.HA Cpr.
Lateral areas tuberculate, without pustules ; diagonal line peb- bled ; central areas with lines of tubercles irregular, tubercles smal- ler. Hairs of the girdle larger, very close.
( '. r.i AMI < arpenter.
Shell ovate, elevated, brown-olive or maculated with whitish and hlui.-h. Intermediate valves strongly mucronate, interstices curved, margins >omewhat rounded. Posterior valve depressed, excavated, the mucro >mall. superior; jugal and lateral areas indistinct : sur- with granules and ornamented with small close points. Sutural plates large, curved; sinus tlat : insertion plates acute, the intermediate valves with 1, terminal valves l!) slits. Girdle hairy, -pines .-mall, erect, tlat.
• adth 3i,alt. 1 mill.; divergence 110°.
it Ian,
( ii i i-.ri.i i i: \.
.' l,t'i>i<1»i>l>'iirn.< l»,inii <Yi:., Ma/. <'atal. p. l'.»7. - t '/m In/,/. bnmii ( Yi;. MS.
Diilcrs from L. Macandrei in l.<-in- longer, with lip mucronated and rounded at tin- extremities, the posterior heini: hol- lowed out and the rot much elevated, without conspicuous middle portion or lateral areas. The only perfect specimen found Acma-a fax-icularis) displays no trace of solid scales. Tin- account of the interior is taken from :i lame central and -mall anterior valve supposed to belong to this species from their agreement in other respects.
C. FLAVE8CEN8 Carpenter. Unfigured.
Shell ovate, much depressed, yellow, spotted with orange. Valves wide, somewhat rounded at the margins, the interstices curved, strongly mucronate. Lateral areas and jugum indistinct ; mucro small, superior. Entire surface furnished with close granule-, scarcely punctulate ; girdle thick, nearly smooth, furnished at the margin with delicate erect flattened spines. Sutural plates large, arcuate; sinus large. End valves with about 10, intermediate valves 1 slit. Length 4, breadth 2|, alt. f mill.; divergence 150°.
Mazatlan, on shells.
Chiton flavescens CARPENTER, Maz. Cat. p. 198.
This is the least uncommon of the small Chitons, six specimens having been found of it. It is distinguished by its yellow color, great depression and small strong mantle margin, without covering, except at the margin where a fine row of transparent flattened hairs may be seen. The smaller lobe on the margins of the inner valves is bounded by two rows of holes which proceed to the jugum. (Q/r.)
C. LITRIDA Sowerby. PI. 12, figs. 53, 54.
Shell oblong, rather elevated, ashen ; front valve, lateral areas of intermediate valves and posterior valve coarsely granulose ; central areas longitudinally sulcate, threads between the grooves granulose. Length 30, breadth 15 mill. (/%.)
Sta. Elena, W. Colombia, on stones in 5 fms.
Chiton Inridus Sown., P. Z. S. 1832, p. 26 ; Conch. Illustr. f. 20. —REEVE, Conch. Icon. f. 85. — Chiton srubrtcidus SOWB., P. 7.. S. 1832, p. 28 ; Conch. Illustr. f. 21 .— RKKVI:, t, 15, f. Sl.—IschnocJiiton parallelus CPR., Ann. and Mag. N. Hist. (3), xiii, p. 314. — Isch no- chiton (f var.) prasinatm CPR., /. c., p. 314. 3
34 < ii. i I'.IM.I TRA.
To this species Cnr|>enter unites C. teabrimhus Sowl). pi. \'l.
• •I aii.l !.«•/, nix'/ufon }><irallelusCpr., afigureof which, drawn from a Carpenteri; men from Cape St. Lucas, is given on pi. 12,
fig. 50. It is likely that C. columbiensis should be added to the synonymy, as it presents no differential characters of much value.
Var. PARALLEL* Cpr, PI. TJ, fig. 50.
The specimen In-fore me of the form jtarallelus, measures 17 by 11 mill. It is rather acutely carinated, the sides slopes nearly straight. There are 17 beaded longitudinal threads on each side of the central areas, and from 6 to 7 rows of separated, rounded ? erect tubercles on each lateral area. The lateral areas are decid- dly elevated; the mucro is slightly prominent. The girdle has sparsely scattered hyaline short hairs. The gills continue as far as the front end of the foot. The outside is reddish, marbled with darker and white, the girdle dark ashen. The interior is bluish- white.
Cape St. Lucas.
The >tyle of sculpture is the same as in C. gemmea, but the shell is much broader than in that species.
Var. r i :. \SINATA Cpr.
lihir to jHir'i/lefn, but vivid green; lateral areas irregularly ornamented with series of tubercles. Cape St. Lucas.
Var. « "i.i MI;II NMS Sowerby. PI. 12, figs. 51, 52.
Shell ovate, a little depressed, ashen ; end valves and lateral MPBAS --parsely gnumlote; Central areas longitudinally <rrunose-lin- eate. (S6y.) Length 31, breadth 18 J mill.
Bay of Panama, under stones at low water.
C.co/»'wiAi>//*MSowi:.. P. /.S.I 832, p. 58; Conch. Illustr. f. 15.— L'I.I.VI . Conch, leuii. f. 82. — Clwtopleura columbiensis Sby. CPR., m§.
Carpenter says: Mucro slightly in front of the middle, sul>- planate, the posterior part exeiirved. Interior: posterior valve with *. anterior valve !), central 1 >lit. Teeth obtuse, scarcely roughened; eaves large; sinus narrow, moderately deep. Girdle leathery, with a f.-w corneous hairlets. . . . One of Colonel Jewett's specimens is of a uniform dark chocolate color, but parts of some ,,f the valve- are of a variegated olive.
Of another specimen ( 'pr. writes: One specimen of the wiliri- culus type. Girdle finely hairy. K'.d. with dark girdle. On each
» ii i POP1 i i i: \. of the central RFCM llieiv an- l»i tinr row- of h»-ads nnt
developed ; jugular araai not defined ; -idr areai u ith in
larly >cattetvd grains. Mucro central, d«-pi .--( •<!.
Length -s, breadth 17 mill.
< 'arpenter seem- di-po-cd to unite to Columbian.*;.* tin- -pecies described as ncnhr'n-nlun and luritlii*, the former of these two being leaB, the latter more beaded than the typical fiolumbittufa In case this view is correct, columbiensis will fall into the synonymy of luridut.
C. ISABELLEI d'Orbigny. PI. 13, i\^<. ">", 58.
Shell oblong, brown ; back carinatcd ; front valve and lateral areas of the intermediate valves radiutel}' granulate; central treat longitudinally granulose-striate. Length 22 mill. (Orb.)
9 Bay of San Bias, Patay<>
Chiton isabellei ORB., Voy. dans 1'Amer. Mr rid. p. 488, t. «;:>, f. 14-1!). — Tonicia isabellei ROCHEBR., Cap Horn, p. 138. — Chceto- pleura isabellei CPR. MS.
Allied, by its granulated strife, to C. peruvianus, but narrower, more carinated, the girdle smooth. ( Orb.*)
The gills are figured as continuing almost to the front end of the foot. In the absence of any information regarding the insertion plates it is impossible to say whether this species is a Tmnriit or a Ckcetopleura ; if the latter, the girdle is probably not truly smooth. In sculpture it seems near to columbiensis and its allies.
C. DIEFFENBACHII Reeve. PI. 13, figs. 65, 66.
Shell somewhat elongately ovate ; valves covered with very min- ute raised dots; lateral areas scarcely raised ; posterior valve umho- nated ; variegated with red, green and yellow ; ligament horny, arenaceous. (Rve.)
Newcastle. A u.<tr<dii.
Chiton dieffenbachii Rvi-;., Conch. Icon. t. 2'J, f. 14!'; species no. 148.
The locality must be regarded with doubt until confirmed. It mav prove to be from Peru, and a synonym or variety of ( '. Inr'nlt Sowb. The figure is enlarged.
C. APICULATA Say. PL 13, figs. 75-79. Shell oval, elevated, light butf or aaheo, unicolored <>r having
black patches at the sides or on the ridge (sometimes red or purple
36 < I LF/TOPLEURA.
in Southern specimens); carinated, the side-slopes nearly straight; central areas having headed threads, lateral areas and end valves havin.ir numerous scattered pustules.
The lateral areas are distinctly defined, raised, and bear numer- ous erect rounded pustules, irregularly scattered, not arranged in rows. The end valves have the same sculpture, but the pustules are more crowded. The central areas have minutely beaded longi- tudinal thivads, f'r«»m 15 to 20 on each side. The umbo of the pos- terior valve is in front of the middle, and rendered slightly pro- jecting by the concavity of the slope back of it.
The interior is white or stained with leaden in places. The sutural plates are rounded ; sinus moderate but angular. Slits of anterior valve 11, central valves 1, posterior valve 9-11. Teeth slightly crenulated ; eaves short, solid.
Girdle narrow, bearing sparsely scattered, transparent, short bain.
Gills extending almost to the forward end of the foot, 24 branchiae on each side.
Length 17, breadth 10 mill.
Length 16, breadth 12 mill.
Cape Cod, Massachusetts, to Florida.
Chiton apiculatus SAY, Amer. Conch., edit. Binney, p. 231. — S,,wi:.. Conch. Illustr. f. 140.— DsKAY, Moll. N. Y. p. 164, t. 10, f. 201, 202.— GOULD, Invert, of Mass. (edit. Binney), p. 258, f. 522. — Chcetopleura apiculata Say, CPR. Ann. Mag. N. H. (4), xiii, p. 120.— DALL, Proc. U. S. Nat. Mus. 1882, p. 410 ; Bull. 37, U. S. Nat. Mus., p. 172, t. 51, f. 10. — Chiton labeculatus KEEVE, Conch. Icon. t. 18, f. 108.
The tubercles of the lateral areas and end valves of this species show a lack of arrangement into radiating rows, which will readily distinguish this from other species.
It i> ijuitc commonly distributed along the Atlantic coast of the Tinted States from Nantucket to Florida, and has also been reported from Haiti.
The North, in examples are generally buff or ash colored, some- times with patches of black; but in a suite before me from Marco, Florida, one specimen is scarlet and another purplish-pink. These southern examples, whilst agree inir with the typical form in sculp- , are smaller and comparatively narrower. (Figs. 78, 79.) A specimen from Angfaeea, New Jersey, baa the lateral areas and
< ii BTOPLE1 i: \-
end valves pink, the central areas Imll'. :in<l each valve ha.- a trian- gular black patch at the dorsal ridiri-. The ^ii-dle i- alternately hull' and pink.
C. CANDI8A TUB Shuttle worth, Unfigured.
Shell elliptical, convex, dull waxen, the hack sometimes handed with white; terminal valves having large white granules, which are much elevated, sparsely and somewhat concentrically arrai Median valves subcarinated, the central areas having smaller whit- ish granules, arranged in straight necklace-like series, crowding at the umbones; lateral areas conspicuously elevated, having large, remote, irregularly placed granules. Entire surface covered with a very minute, chaffy puncticulation. Girdle narrow, waxen, marbled with pale brown; chaffy-pustulose, and having pellucid, corneous white setae here and there, especially at the insertions of the valves.
Length 8-9, breadth 4^-5 mill.
Guadeloupe, on dead valve of Cardium serratum.
Chiton (Chwtopleura) candisatus SHUTTL., Jour, de Conch. 1856, p. 168.
Apparently closely resembling C. apiculata Say, in pattern of sculpture.
C. JANEIRENSIS Gray. PI. 13, figs. 59, 60.
Shell oblong, elevated, rather narrow ; dorsal ridge somewhat angular, olive-ashen or brownish ; strongly sculptured, the mucro in front of the middle, rather prominent.
Lateral areas strongly elevated, sculptured with four coarse, granoseribs; anterior valve having 11 to 18 such ribs, usually having a tendency to be in pairs or to split. Central areas having about 12 granose acute threads on each side of the jugum, parallel with it.
Interior white, sutural plates rounded ; sinus shallow ; anterior valve with 10, median valves 1, posterior valve 9 slits. Teeth solid, eaves wide, solid.
Girdle having a few delicate short hairs.
Length 18, breadth 9 mill.
Gills reaching the neck.
Key West, Florida, to Rio Janeiro, Brazil.
Chiton janeirensis GRAY, Spicil. Zool. p. 6, t. iii, f. 8, 1828. — SOWB., in Zool. Beechey's Voy., t. 40, f. 2. — REEVE, Conch. Icon,
38 CH-KTOPLEURA.
t. 19, f. 116 (not t. 15, f. 81).— SOWB. Conch. Illustr. f. 56.— Chcs- toplt irensis CrR. MS. ; C. apparata and Callistochiton rufi-
costaim CPR., olim. — Cluetopleura janeirensis DALL, Bull. 37, U. S. Nat. MH-. ]>. M'1—i'hitnn segmentatus REEVE, Conch. Icon. t. 23, .. — / 'It if on (Chcelopleura) asper SHUTTLW., Jour, de Conchyl. 1856, p. 169.
Tli is species is much elongated, about twice as long as broad- The sculpture of the end valves and lateral areas consists of coaix -. nodulous ribs, which are quite unlike the clear-cut pustules of C. meet, etc.
Young specimens have only two or three nodulous ribs on the lateral areas.
The C. segmentatus of Reeve (pi. 13, figs. 61, 62) differs in no way from the type.
C. SPINULOSA Gray. PL 13, figs. 63, 64.
Shell ashen, partially tessellated with dark and light at the sutures, and stained with brown on some of the jugular areas. Jugum very acute, elevated. Mucro median, not much raised, the posterior slope very concave. Jugal area not distinct; central areas having about 22 rows of very fine granules on each side of the otherwise smooth areas ; lateral areas much raised, having about 10 rows of radiating grains, separate, sparse; grains very irregular and sparse on terminal valves.
Interior: Anterior valve with 10, central valves 1, posterior valve 9 slits. Teeth not very sharp but Ischnoid, the posterior slightly niLrulose. Sinus smooth, channelled, broad, deep, the cting jugular sculpture of the outside giving a faint appear- ance of denticulation. Eaves moderate, not spongy. Interior whitish, with two rays of chestnut.
Length 31, breadth 15* mill.
Rio Janeiro.
Ch'r nlosus GRAY, Spicil. Zool. p. 6, t. 6, f. 7, 7a. — Sowb.,
Conch. 111. f. 84, 84a.— REEVE, Conch. Icon. t. 27, f. 90.— Chceto- •a CI-R., MS.
It is doubtful whether the C. spinulom of Sowerby, Reeve and Carpenter is the same as the form originally so named by Gray. Carpenter's description, given above, is drawn from a single speci- men, which apparently served Reeve for his illustration. This specimen i- much injured, having lost its girdle, and some of the
. 1 1.1 K.l'l.l IRA. 89
valves ami teeth an- broken. Tin- ii.L'im-s ln-rr- -/iven an- from Reeve.
C.*8owi-:i:uiANA Reeve. PI. 13, figs. 67, 68.
Shell <»hlon.i:-ovatr, valves having the lateral areas (•••ii-pieuously elevated, granoaely ridged throughout, riders of tin- central areas much tiner. Dull yellowish-brown, with a triangular \vhiti.-h along the umbonial summit of each valve. Ligament hornv. CRw.)
Rio Janeiro.
Chiton janeirensis Gray, REEVE, Conch. Icon. t. !;">, f. 80. — C. sowerbianus REEVE, /. c., in note under species No. 116, May, 1847. — Sowerbyi REEVE, /. c., expl. of pi., detail of sculpture, sp. 80. — Sower by anus REEVE, I. c., index to Chiton.
Carpenter says : Seems to me a coarse var. of spinulosa Gray. Rio Janeiro. Very like apiculata, but with more swelling side areas. The sinus represented in the sculptured figure of Reeve is only the part left after the swelling of the sides. With this impression, I did not think it necessary to examine the single specimen in Cum- ing's collection; but on further examination I thought it might be a distinct species and described it thus : Valves arched ; jugum rather rounded ; jugular area finely striate. Central areas having about 18 nearly parallel ribs on each side, the interstices decussated between the ribs, which are sharp (not in necklaces). Lateral areas swelling, with 6 to 8 very close rows of coarse granules, inter- calating, and no spaces between. In the end valves they go into close radiating rows. Mucro in front of the middle, depressed, the slope behind it very concave. Girdle with very few scattered hairs. Interior: Anterior valve with 9, central 1, posterior 8 slits; teeth sharp, normal ; eaves conspicuous, rugulose, but not spongy. Sinus moderate, sharp, deep, channelled.
Length 26£, breadth 133 mill.
C. ARMILLATA Carpenter, n. sp. Unfigured.
Shell subelongate, elevated, the jugum acute; mucro a little in front of the middle; reddish-brown, maculated with darker. Valves quadrate, scarcely apicate; jugal area scarcely defined; central areas having 14 to 20 lines of small granules on each side, the interstices flat. Lateral areas scarcely elevated, having sub- radiating, distant, sparse granules; entire surface nearly smooth, very minutely punctulate and striatulate under a lens. Interior:
4U TONICELLA.
Posterior valve with 9, anterior 9, central 1 slit. Teeth acute ; eaves conspicuous ; -inns narrow, deep, smooth. Girdle leathery, minuU'ly dowpy-ecaled and having occasional delicate, corneous hair*. Opr.) Length 25, breadth 11 1 mill.; divergence 100°.
Is. Gorriti (Mus. Cum. No. 34).
One of the specimens is light colored on the jugum of each valve, with a triangular spot. (Q/r.)
Genus VIII. TONICELLA Carpenter, 1873.
Tonicella CPR., Bull. Essex Inst. v, p. 154, 1873, type C. marmo- reus Fabr.— DAI.I, IVoc. U.S. Nat. Mus. 1878, p. 324.— Tonin.i, in part of (iK.vv, ADAMS, et at. — Boreochiton, (part) SARS, Moll. Reg. Arct. N..rv. p. 116, 1878.
Valves, sutural plates sinus and teeth as in Ischnochiton, but the • are spongy ; girdle as in Tonicia, leathery, smooth or nearly so. Gills extending forward from two-thirds to three-fourths the length of the foot.
Distribution, Northern Atlantic and Northern Pacific shores.
This irrouj) differs from Trachydermon, Callochiton, Ischnochiton, Ckitniileurn, etc., in its naked, scale-less girdle ; from Stereochit.m in having a single slit in the median insertion plates. It differs from T»n iria, to which genus the species of Tonicella were formerly referred, in the non-pectinated insertion plates, spongy eaves and shorter gills.
The surface of the valves is smooth, or evenly microscopically granulated.
The essential differences between Tonicella and Chtptopleura seem to !»«• bridled by several species which are intermediate in charac- ters of gills, girdle or both. The former should perhaps rank as a subgenus rather than a genus, as the pattern of sculpturing of the valves, shorter gills and spongy eaves are about all there is to sep- arate the two groups.
Under Tonicella, as a subgenus, I include the peculiar type Cyano- pro posed for the reception of the C. hartwegiiCpr. The genus will therefore be divided thus:
Suhgenus TONMT:I.I.A s. s. Teeth rather long; valves nearly smooth ; gills shorter than the
Subgenus CYANOPLAX Pils.
(h stumpy, bi- or tri-loh<-d ; valves granulated; gills ambient.
rONIOBl 11
TONIOKLUI < '\>r. T. M\I:M<>KI:A Fahrieius. 1M. 10, fiir- s L5,
Shell oblong or uvul, I'levah'd. ratln-r acntclv angular; hull',
closely speckled and maculated with -lark n-d. as in Tr<ic/«/>l>
ruhcr. Surface denttly, microscopically granulated, but apparently
smooth. Lateral areas not distinct. Valves beaked, \im\tn «.f pos- terior valve slightly prominent, central.
Interior rose tinted; anterior valve with 8-10, median valves 1, posterior valve 8-9 slits. Sutural plates broad, rounded; >irms deep, angular.
(Jirdle leathery, nude.
The gill rows extend forward three-quarters the length of the foot, each containing 20-25 brand) in-.
Length 40, breadth 24 mill.
Length 27, breadth 16 mill.
North Atlantic : Massachusetts Bay to Greenland; Holland to Ireland and northward. North Pacific: Aleutian Islands and Japan.
Chiton marmoreus FABR., Faun. Gronl. p. 420, 1780. — FORBES & HANLEY, Hist. Brit. Moll, ii, p. 414, t. 58, f . 2 ; t. 59, f. 4.— JEFFREYS, Brit. Conch, iii, p. 227 ; v, p. 199, t. 56, f. 7. — Chiton, (Tonicia) marmoreus Fabr. Smith, Ann. and Mag. N. H. (4) xx, p. 139 (Franklyn Pierce Bay, Greenland). — Tonicella marmorea Fabr. CPR., Bull. Essex Inst. v, p. 154, 1873 ; Ann. Mag. N. Hist. (4) xiii, p. 121.— BALL, I c., vi, p. 124 (anat.) ; Proc. U. S. Nat. Mus. 1878, p. 324.— Chiton ruber SPENGLER, Skrift. Nat. Selsk. iv, p. 92, not of Linne. — Chiton hvvigatus FLEMING, Edinb. Encyc. p. 113, t. vii ; Brit. Anim. p. 290.— REEVE, Conch. Icon. t. 27, f. 179. — / Chiton punctatus STROM, (teste JEFFR.) Acta Nidr. iii, p. 433, t. 6, f. 14.— Chiton latus LOWE, Zool. Journ. ii, p. 103, t. 5, f. 6, 7.— SOWB., Conchol. Illustr. f. 113. — Chiton fulminatus COUTH., Bost. Journ. Nat. Hist, ii, p. 80, t. 3, f. 19. — GOULD, Invert. Mass, i, p. 14*, f. 3. — Chiton pictus BEAN, in Thorpe's Brit. Mar. Conch, p. 264. — Chiton flemingius LEACH, Moll. (Jt. Brit. p. 230. — Boreo- ch'doH marmoreus Fabr. SARS, Moll. Reg. Arct. Norv. p. 116, t. 8, f. 3.
This species has very much the color pattern of C. ruber, Imt may readily be distinguished by its nude, leathery girdle. Sars was evidently led by this superficial resemblance to create his genus
•IL' TONICELI A.
Boreochiton for the two forms. The Greenland and East American s|M<im.n> arc more elevated and generally larger than the British form, which might retain the varietal name latus Lowe.
Middendorff found the number of slits variable in his specimens fn>m the White Sea and the Arctic coast of Russian Lapland, the anterior valve having 5 to 7, posterior valve 6 to 9 slits.
T. SUBMARMOREA Middendorff. PI. 10, figs. 16-24.
Shell oval, rather depressed, rather smooth and shining, the entire
sui face seen under a lens to be very minutely, regularly and closely
•//•/». Lateral areas scarcely distinct, slightly swollen. Color
rosy or yellowish-white, closely painted with spots and flames of red.
Interior rose colored ; terminal valves each with five slits.
< iirdle smooth, shining, yellow or brown.
Uranchia' median, consisting of about 24 plumes.
Length 38, breadth 24, alt. 12-13 mill.
Japan, Okhotsk Sea ; Aleutian Is. to Sitka and Fuca Strait.
C. submarmoreus MIDD., Bull. Acad. Sci. St. Petersb. iv, 1846 ;
Mai. Ross, i, p. 98 ; Sib. Reise. p. 178, t. 14, f. 7-10 ; t. 15, f. 7, 8.
— Tonlrcll'i xnbmarmorea Midd., DALL, Proc. U. S. Nat. Mus. 1878,
p. 296, t. I, f. 7 ; p. 327 ; I. c. 1886, p. 210.— Chiton insignis REKVK,
Conch. Icon. t. 22? f. 148, 1847.
This species is readily distinguished from T. lineata by its micro- scopic granulation ; from T. marmorea by its more depressed shell, different color-pattern, etc.
T. MM: A i A Wood. PI. 11, figs. 25-28.
Shell oblong, rather low, roundly arched or subcarinated. Sur- face smooth, shining, ground color light reddish. End valves con- centrically marked with black-brown lines bordered above with white, intermediate valves having similarly colored longitudi- nal lines, sloping obliquely backward, the ridge or jugum of each valv. havinir a light triangle with a narrower dark one in the mid- dl«- on some valves. Occasionally some valves are wholly dark brown, unmarked.
Lateral areas scarcely raised ; umbo of posterior valve in front of the middle.
Interior white, more or less tinged with rose color. Sutnral plates broad, rounded ; sinus deep and angular. Anterior valve with 8-10, median 1, posterior valve 8-10 slits. Teeth short, espe-
TONH i;u.\. 43
cially in the p(»terior valve, and blunt, in adult- dceidedly cn-ini- lated at the tips and obsoletely fissured ouf.-ide. I :i:ill.
(Jirdk' leathery, apparently smooth and nude, brown in dried
specimens.
Gills extending forward two-thirds the, length of the foot, com- posed of 27 branch ire cadi.
Length :>7, breadth 20 mill.
Length 30, breadth 15 mill. ; divergence 120°.
From Bering Strait southwestward to the Okhotsk Sea and Japan, southeastward to the Bay of Monterey, California. Aleutian Is.
Chiton lineatus WOOD, General Conchology p. 15, t. 2, f. 1 1815— MIDD., Mai. Ross, i, p. 109, t. 12, f. 8, 9.— SOWB., Conch. 111. f. 77.— RKEVE, Conch. Icon. t. 7, f. 33.— Tonicia lineata Wood, H. & A. AD., Genera Rec. Moll, i, p. 474. — Tonicella lineata CPR. MS., p. 38.— DALL, Proc. U. S. Nat. Mus. 1878, p. 326.
In many old specimens of this species the teeth are distinctly, though obsoletely crenulated and striated outside, presenting an approach to Tonicia.. The slit in the median valves frequently has its edges thickened, and there is a distinct notch on each side of it.
This is one of the handsomest north Pacific Chitons. It is read- ily distinguished from T. marmorea and T. submarmorea by the absence of microscopic granulation of the surface, as well as by the pattern of coloring. Dall writes :
The painting of this very characteristic species is very variable, even on different valves of the same individual. Nothing can appear more distinct than the coloration of typical specimens of some varieties, but in a large series the differences do not hold equally good. The number of slits is also somewhat variable, occa- sional abnormal or injured specimens having only six or seven slits in the tail valve. But fine and normal specimens of both varieties show no more than individual variations.
Middendorff, while pointing out the distinctions between the fol- lowing species and T. marmorea, appears to have overlooked the connection between the former and T. lineata and his description does not always agree with his figures.
From Tonicia lineolata Sowerby, from South America, besides the internal generic characters, the exterior differs by the absence of punctures and raised granules at the sides.
44 TONICELI-A.
T. SACCH A i : i N A I )al 1 . Unfigured.
Shell small, oblong, the entire surface painted with lustrous red and whitish. Urabo subcentral, inconspicuous. Lateral areas indistinctly raiaed ; dorsal area blood colored, reticulated in quin- cunx. Anterior valve having 10-11, posterior 8-10, median 1 slit. Teeth small, spongy ; sinus small ; eaves spongy, moderate, (•irdle leathery, (iills median. Length 6£, breadth 4 mill.
i ami Shumagin Is.; Kyskn, Utialashka, and Koniu*hi, 8 fa&, on stones; St. Paul, Pribiloff Is., 15 fms.
i it-ell n miccharina DALL, Proc. U. S. Nat. Mus. 1878, pp. 2, 827.
This interesting little species has the luster of rock-candy, through which the microscopic reticulation is barely perceptible. It is marked in all the specimens obtained, by the red wine colored dor- sal areas contrasted with a waxy white color of the lateral areas, rendering its recognition easy. The girdle is dark, leathery, nar- row, slightly pubescent, and furnished at its extreme margin with a fringe of fine spiny hairs or spicules, as in T. marmorea.
T. SITKKNSIS Middendorff. PL 11, figs. 29, 30, 31.
Shell depressed, smooth, the lateral areas indistinct, under a lens seen to be sparsely granulose ; reddish. Anterior valve having 8, 1". -tenor 10, central 1 slit. Gills posterior.
Length 10, width 6 mill. ; divergence 130°.
Sitka.
C. sitketms MIDD., Bull. Acad. Sci. St. Petersb. vi, p. 121, 1846 ; Mai. Ross, i, p. 112, t. 13, f. 1, 2.— Not C. sitkensis Keeve, 1847.
I >• scribed from a single specimen, and not found by later collec- Middendorff 's figures and description do not agree upon sev- t-ral points. The anterior teeth are figured as grooved outside, a character also seen in T. lineata.
Subgenus CYANOPLAX Pilsbry, 1892.
Valves resembling those of Ischnochiton, but having the teeth MMiit. obtuse, crenulated or hi- or trilobed at their tips; and the • •:!'.• — [">i,j\ -. (iirdle leathery, miniftely papilloBC. (Jills extend- ing to the anterior end of the foot.
I)it}!-r> from ( '/mtojtfeura in the spongy eaves and papillose, not Jfiini Lrir<llc; from ToniceUa in the long gills, different girdle, stumpy, bilobed anterior teeth, etc. It might be considered a
K.NK i i i.\.
were it n«.( for tin- peculiar Uunt tei-th, ainl.i.-nt .irills and almost scalelcss uinll.-.
The girdle seems t<» he dusted with a few small, .-nmot.il white
scales in places.
On account of the spongy caves and hairless irinllc, I include this submenus in Tnnlcella rather than in ( 'Inrtopleura ; In- close all'mitics with l)oth of these groups renders the question of
its position peculiarly dillicult.
T. H.\I:TWI-:<;II (1arpenter. PI. 14, figs. 81, 82, 83, 84, 85.
Shell oval, rather low, the dorsal ridge obtusely rounded ; dull olive green, generally having a pair of lighter stripes on the rid^e of each valve with a black blotch outside of the light dashes. Girdle (fig. 82) rather narrow, dense, microscopically cl" granulated.
The tail valve is convex as a whole, but the subcentral umbo is not conspicuous. The entire surface is very closely microscopically granulated, and bears larger wart-like granules irregularly scattered over the minute sculpture, these warts being much more numerous upon the lateral areas (which are otherwise rather ill-defined) and the terminal valves.
The interior is of an intense blue-green color. Sutural plates rounded, leaving a wide, angular sinus. Insertion plates shorter than the eaves, blunt, the anterior valve having the teeth bi- or tri- lobed, the posterior valve having them crenulated. Slits of ante- rior valve 10-11 ; median valves 1 ; posterior valves 9-12. Eaves spongy.
Gills extending forward to the front end of the foot.
Length 30, breadth 17 mill.
Length 27, breadth 18 mill.
Vancouver Island to Magdalena Bay, Loiver California*
Cliiton hartwegii CPR. P. Z. S. 1855, p. 231 ; Trachydermon liart- wegii CPR. B. A. Rep. 1863, p. 649. — Chcetopleura hartwegii CPR. IMS. p. 45.— DALL, Proc. U. S. Nat. Mus. 1878, p. 329.
The prominent differential characters of this species are its sys- tem of sculpture, vivid blue-green interior, slightly spongy ea\vs stumpy, bilobed teeth of the front valve, etc.
46 8CHIZOPLAX.
Yar. M ITAU.II Cjir.
Umbo flatter; valves broad, non-swelling, squared at the sides, and not beaked or waved. Posterior valve having 11, central 1, anterior 8 slits.
Habitat same as hartivegii.
Chiton uutt'illii CPR. P. Z. S. 1855, p. 231 ; Trachydermon n., ( !•!:. Suppl. Rep. B. Asso. 1863, p. 649 ; CfioBtopleura n., CPR. MS., in Dall, Proc. U. S. Nat. Mus. 1878, p. 330. I am unable to separate this form from hartwegii, as transition linens are numerous.
T. I.IPUNCTATA Sowerby. PL 14, fig. 90.
Shell ovate, smooth ; green, variegated with black and white ; margin concolored, generally having a white spot on each side between the first and second valves, marginal ligament smooth. I.« ngth 12£, breadth 6} mill. (Sowb.~)
Liner Lobos Island, Peru, under stones at low water.
C. bipundatus SOWB. P. Z. S. 1832, p. 104; Conch, lllustr. f. 27.
This species varies much in coloring, some specimens being nearly Mark, others light green, and some much and prettily varied. In almost all a white mark may be observed on the margin just behind the anterior valve. (Sowb.)
Carpenter's notes on the types areas follows: Posterior valve having 9, central 1, anterior valve 9 slits; teeth smooth, stumpy ; eaves very short, spongy. Girdle smooth with extremely short, • re<l hairs, and two white spots at the sutures of anterior valve. Valves beaked, but they seem to have no pattern of sculpture, only a very close quincunx (arrangement of granules). Looks like a Tr>t<-l,>j<Jermon without scales. The mucro is in front of the middle, the slope behind it concave. Color greenish, generally with u white blotch behind.
Length 12, breadth 7 mill.
Congeneric with and very like a small nuttaUii.
< -mis IX. SCHIZOPLAX Dall, 1878.
Schizoplax DALL, Proc. U. S. Nat. Mus. p. 2, Jan., 1878 ; 1. c. p. 328.— ( !p& M.S. Type Chiton brandtii Midd.
Shell and girdle as in Tonicella, except that the median valves have a central jugal slit filled with cartilage, narrower in front;
BCBIZOFLAZ, 17
very spongy ; gills extending three-fourthl tin-
of the loot.
This form, whilst allied to Tonicelta, differs from all other kn Chitons in the curious slit along the jugum of each of the median valves. This slit is wedge-shaped, narrowing to a point in front, where it is lost in the spongy jugal sinus. The slit is filled with a cartilaginous substance resembling the ligament of a bivalve. Out- side there is a corresponding furrow not extending to the terminal valves.
The tegmentum, or external layer of shell substance, is remark- ably porous where exposed at jugal sinus and eaves.
S. BRANDTII Middendorff. PI. 11, figs. 32-37.
Shell oval, rather elevated, the jugum rounded; olive-brown, streaked, maculated or clouded with blue, sometimes chestnut. Umbo central, irregularly planate. Lateral areas scarcely defined. Entire surface smooth, seen under a lens to be finely granulated in quincunx. Girdle narrow, olive-ashen, maculated, closely beset with minute spines, but appearing almost smooth to the naked eye. The median valves have a sharply cut longitudinal median sulcus. The jugal sinus is moderate, deep, scarcely laminate, conspicuously spongy. Eaves small, very spongy. Anterior valve with 11, pos- terior.ll and median valves with 1 slit. Gills about 22, subambient.
Length 16, width 5 mill.; divergence 140°.
Shatttar Bay, Okhotsk Sea; Aleutian Is. eastward to Sltka Har- bor, low water to 12 fms., on stones and shells.
C. brandtii MIDD., Bull. Acad. Sci. St. Petersb., vi, p. 117, 1846 ; Mai. Ross, i, p. 128 : Siber. Reis. p. 174, t. 15, f. 1-6.— Schizoplax brandti CPU. MS.— DALL, Proc. U. S. Nat. Mus. 1878, pp. 2, 328.
This very remarkable species is very prettily marbled with olive, chestnut and blue ; the girdle generally dark olive, dashed with ashy spots and in fine specimens having a pubescent appearance. The slit is occupied by a cartilaginous substance of a dark brown color, most visible from within. It is quite possible that it may reach as far south as Puget Sound.
The soft parts are yellowish-white. The gill rows extend three- fourths of the length of the foot forward from their posterior termina- tion, and each contains about twenty-two branchia?. Mantle-edge thick, plain ; veil small, plain. Muzzle small, plain, with two large squarish lappets at the posterior corners. The supposed oviducts
48 CALLOCHITON.
open on each side through a small rounded papilla in the vicinity of the third or fourth bronchia, counting forward, and between the liiu • of the gill row and the side of the foot. (Da//.)
Genus X. CALLOCHITON Gray, 1847.
. KAY, P. Z. S. 1847, pp. 126, 168 ; type Ch. Icevis.— Snrrri.KW Bern. Mittheil., Jimi, 1853, p. 65. — Callochiton GRAY, < iuide Syst. Dist. Moll. B. M. p. 181, 1856.— Callochiton CAEPKN- 1 1 i: .!/>' 1*71, and of DALL, Proc. U. S. Nat. Mus. 1882, p. 286, not Cnllochiton of Carpenter's earlier writings (P. Z. B. 1865, p. 276, etc.), — Callistochitnii.
Valves exposed ; insertion plates rising out of porous or spongy — and cut into numerous teeth; sutural plates connected or continuous across the shallow jugal sinus.
Two subgenera are recognized by Carpenter:
Subgenus CALLOCHITON (restricted).
< iirdle covered with a smooth, compact layer of very small dia- mond-shaped scales. •
Subgenus STEREOCHITON Cpr.
( iirdle leathery, more or less downy, frequently naked when the delicate scales are rubbed off.
Subgenus CALLOCHITON s. sir.
The essential characters of the restricted genus Callochiton are correctly stated by Carpenter as follows: (1) The insertion plates are broken up into very numerous teeth rising out of spongy eaves ; (2) that these have a tendency to become propped outside ; (3) that the sinus is a mere wave in the otherwise united branches of the sutural lamina ; (4) that the mantle is reticulated with what look like diamond-shaped scales, which are only the points of long, flat- tened, closely appressed corneous bodies, not found on any other Chiton. For Gray's second group, in which the peculiar covering is not seen, a subgenus should be created, unless indeed the species may rank under Trachyradsia. For two species with a mantle intermediate between ( 1m topleura and Tonicella I have establi.-hed a subgenus Stereochiton. Of the whole series there are very few species known. All of them are rare and display very little sculp- ture on the val\. ~.
( ALL. HIM l<>\. H»
C, i BVIS Montagu. I'l. !» figs. !»:>-<)9.
Shell oblong, rather elevated and rather acutely earin;i(ed. tin- Bides Straight Or convex. Color very variable, but niainlv vellow- ish-olive, spotted and marbled more or less with dark rod «»r n-ddi.-li, but green often predominating. Girdle olive with creamy spot-, and often red patches.
The valves are slightly beaked and apparently smooth, but under a lens a fine but half-effaced granulation is seen. The lateral areai are distinctly raised. The umbo is low and in front of the center.
Interior pink-tinted. Anterior insertion plate having 14 to 17 slits, median valves with about 3 slits, posterior valve with 14-K> slits. The teeth rise from very spongy eaves, and are more or less thickened at the sides or "propped." Sutural plates continuous, the jugal sinus indicated by a shallow depression.
Girdle firm, smooth and wide, composed of excessively fine dia- mond-shaped scales.
Length 21, breadth 11 mill., sometimes larger.
British Seas; Mediterranean.
Chiton l(cvis MONTAGU, Test. Brit. p. 2. — REEVE, Conch. Icon, f. 125.— FORBES & HANLEY, Hist. Brit. Moll. p. 411, t. 58, f. 3.— JEFFREYS, Brit. Conch, iii, 226, t. 56, f. 6. — Chiton marginatus of some authors. — C. achatinus BROWN, Illustr. Conch. Gt. Brit. p. 65, t. 21, f. 4, 12, 13, 15. — C. septemvalvis MONT., Test. Brit. p. 3 and C. discprs MATON & RACKETT, Trans. Linn. Soc. viii, p. 20. — Chi- on cranchianus LEACH, Moll. G. B. p. 230. — Lepidopleurus punctu- latus LEACH, 1. c. p. 228. — Chiton dorice CAPELLINI, Journ. de Conchyl. (2), iii, p. 325, t. 12, f. 2, a", b", c", 1859.
This is a rather high and sharply keeled species although depressed specimens occur. It may be known from other Euro- pean Chitons by the comparative smoothness of both valves and girdle, the latter wide and covered with very fine diamond-shaped scales ; by the propped teeth and spongy eaves, the number of slits in the median valves, etc.
The Mediterranean form has been called C. dorice, but I am unable to see that it has distinctive characters.
C. PLATESSA Gould. PI. 10, figs. 1-5.
Shell smooth, entire surface delicately shagreened, terminal valves and lateral areas only with indistinct concentric lines of growth ; 4
50 CALLOCHITON.
lateral areas not prominent, with no radial markings; umbones small, pointed.
Girdle. — With delicate flat elongated scales.
Gills. — Extend along whole length of foot, about thirty in num- ber on each side.
Color. — Central areas yellowish, obscurely mottled with orange ; on some valves there are a central and a lateral pair of pale lines. Lateral areas and terminal valves of a uniform dull orange color, and uniformly spotted with minute black dots, which are absent from the central areas, the posterior border of the valves is orna- nirntrd with alternate lighter and darker spots. Ligament brown- ish, with a few irregular small white flecks and five large white spots, four very large spots extending from the points of junction of the first and second and seventh and eighth valves respectively t<» the edge of the girdle; the fifth spot being in the median line N'riorly. (Haddon.)
Interior. Posterior valve with 14, anterior 16 and median valves with :! slits. Teeth solid, separated, propped outside, bifid or aped. Eaves very spongy, simple, short. Sinus small, wide ; sutural plates united; girdle normal. (Qor.)
Sydney; Port Jackson; Botany Bay ; Australia; (and New Zea- land?).
C.platessa GLD., Proc. Bost. Soc. N. H. ii, 1846, p. 143; U. S. ExpL Kxped. p. :;L>O; atlas, f. 434, 434a, left hand, under Ch. fru- ticosus. — I.rjtiiluji/enru plntessa GLD., Otia Conch, p. 242. — Callo- chiton platessa Old., CPR., tnss. — HADDON, Challenger Rep. p. 1 5.— ' 'It if on i-winns Rve., Conch. Icon. t. 22, f. 14(5, 1*47.— Chiton ver- sicolor A. AD., I'. /. 6, \*~>'2, p. !)2, t. 1(>, f. ~).—Leptochiton versico- lor, ANCIAS, P. Z. S. 1867, p. 223.
There is an error in the lettering of Gould's plate, the figures iM-inir niimlx-red 4:54 instead of 431. There is considerable varia- tion in coloring. C. versicolor, which Carpenter considered a syn- onym, is represented in pi. 10, fig. 6. C. crocinus (pi. 10, fig. 7) is a larger form, length .V> mill., said to be from New Zealand.
C. PRINCEPS Carpenter, n. sp.
Shell large, very flat, oval ; JIILMIIM annulate ; red, streaked with paler and deeper. Posterior valve large, very flat, the median umbo inconspicuous. Lateral areas hardly defined; central valves
OALLOCHIT" .'-1
rounded at the mai-iiins, sometime- (abnormally?) p«-«-t mated.
Knlhv surface roii-pirimiisly hut minutely 'jTaimlat.'d.
Interim-: Posterior valve having 1 7, anterior I *, median va ."> slits. Teeth elegantly radiately propped, curve*! outwunl, tv three lobed, sometimes striated. Kaves short, reddish, sp<.nirv. Inside Iiurht fle<h colored. Sutural plate- joined, hroadly hut
slightly sinuated in the middle. Girdle normal. (Cpr.) Length hrcadth '20 mill.; divergence 135°.
Habitat unknown. (Mus. Cum. No. !)">.;
The complicated external structure of the insertion plates is more beautiful in this than in any other known species, resembling the fret-work of a Gothic pinnacle. It is specially displayed where the eaves have been broken off through accident, and the grooving is displayed under the colored part of the valves, which are there pec- tinated at the edges. It is unfortunate that the locality of this typical species is unknown. (Cpr.)
C. ILLUMINATUS Reeve. PI. 9, figs. 92, 93, 94.
Shell oval, red, rather elevated, the jugum acute ; umbo a little in front of the middle, slightly elevated. Entire surface very min- utely wrinkle-striate and granulose under a lens, the central areas longitudinally, the rest radially. Central areas with slender ele- vated separated threads, parallel to the jugum, 6 to 14 on each side. Lateral areas rather elevated.
Interior roseate. Anterior valve with 15-16, posterior with 11-14 slits, median valves with 1 slit. Teeth acute, quite distant, scarcely propped. Eaves spongy, sinus small, the sutural plates connected across it. Girdle normal, the scales rather large, solid ; sometimes spotted with paler at the sutures. (Q>r.)
Length 16, breadth 10 mill. ; divergence 120°.
Straits of Magellan*
Chiton illuminatus REEVE, Conch. Icon. t. 22, f. 147,1*47.- C. (Callochitoii) illuminatus Rve., SMITH, P. Z. S. 1881, p. 35. — Lepidopleurus illuminatus ROCHEBRUNK, Miss. Cap Horn, p. 141.
There are about 16 gill plumes on each side, reaching three-fifths of the distance forward, according to Carpenter. In having but one slit in the median insertion plates and in the want of props on the teeth this species is abnormal ; in other respects it agrees with Callochiton.
52 CALLOCHITON.
Subgenus STEREOCHITON Carpenter. Stereochiton CARPENTER MS., 1871.— DALL, Proc. U. S. Nat.
Mns. iss-j, ,,. -JM; (type C. castaneus Wood).
Valve- like Callochiton, but the girdle leathery and downy, the scales very delicate and deciduous. In this group the teeth are numerous, the median valves having 5 or more; but on account of tlu-ir narrowness they do not always, have the lateral buttresses or props outside, so characteristic of the teeth of the true Callochi- ton <. The eaves are very narrow, but distinctly porous or spongy, as in Callochiton, and the bottoms of the slits are also coarsely spongy'. The sutural plates are continuous from side to side, the nir.liaii sinus being a mere wave, also a characteristic of Callochiton.. It is therefore obvious that the characters of the girdle alone sepa- rate Stereochiton from Callochiton. In C. castaneus the girdle of moderate sized specimens is always, so far as I know, denuded of most of the covering of downy scales, but under a strong lens the close, fine markings where they were inserted in the girdle may be seen, as well as occasional scattered scales.
Stereochiton externally resembles Tonicella, but it may be at once distinguished from that group by its numerous side slits.
C. CASTANEUS Wood. PI. 9, figs. 86-91.
Shell oval, depressed, dark chestnut brown or variegated with lighter brown. Jugum obtusely keeled ; lateral areas rather distinctly defined, slightly raised. Entire surface very minutely, densely granulated, when seen under a lens ; the granules low, not arranged in distinct lines, but an obscure oblique radiation is more or less visible. Growth striae light. Umbo of the posterior valve some- what in front of the middle, somewhat elevated.
Interior rose colored; Anterior valve with 20, posterior with 18, median valves with 5 deep slits. Teeth rather high and narrow, blunt, not propped, those of the terminal valves frequently bilobed or Lrilobed inside, and obtusely crenulated at their apices. Inter- stices spongy. Eaves very narrow, short, spongy. Sutural plates connected, the jugal sinus shallow. Girdle leathery, bearing (when 'not rubbed off) delicate elongated scales.
Length 42, breadth 28 mill.
Cape of Good Hope.
Chiton castaneus WOOD, General Conchology, p. 13, t. 2, f. 2, 3 ; t. 3, f. L>, :j, 1815.— SowERBY,Couchol.Illustr.f. 114, 115.— REEVE,
BOHNOOHTTON,
Conch. loon., t. f>, f. '.>."». --Nor <\ <VM/////>;//X (J.uoy nor ('. Conth. — C.certitiim* '*//, •/////., RI:I:YI:, Com-h. Icon. f. i;;j.
This Bpeciee IB Variable in colorinir, IteinireitlnT uniform brown or having spots and patches of l)ro\vn on a lighter Around. The interior is always roseate. The numerous narrow teeth, short spongy eaves, spongy slits, etc., readily separate it from other forms.
C. LOBATUS Carpenter, n. sp. PI. 8, figs. 83--S-").
Shell large, flattened, with acute jugum; intense olive colored; iimbo median, the posterior slope concave. Valves scarcely beaked, rounded at the margins. Lateral areas not well defined. Entire surface minutely granulated in quincunx.
Interior : Posterior valve with 20, median valves 5 to 7 (usually 6, the posterior minute), anterior valve 24 slits. Teeth small, deeply separated, and outside very strongly propped, as if bilobed ; interstices deeply spongy. Eaves small, spongy, grooved inside ; sinus subobsolete ; sutural plates connected. Girdle leathery, smooth, under a lens seen to bear short, minute, sparsely placed hairlets. Length 41, breadth 27£ mill.; divergence 130°.
Tasmania. (Mus. Cum. No 19.)
This fine and curious species has the general aspect of Mopalia vespertina (from which it is known at once by the lophyroid mucro) ; the insertion plates, props, spongy eaves and minute sinus of Callochiton ; and a mantle resembling an aberrant Tonicia.
Genus XI. ISCHNOCHITON Gray, 1847.
=Ischnochiton + Tracliydermon -f- Maugerella Cpr.
Valves external, having sharp, slit, insertion plates, the teeth not buttressed. Eaves solid (rarely somewhat porous in s. g. Trachy- dermoii) ; girdle covered with imbricating scales, either flat or con- vex, smooth or striated. Gills typically extending the entire length of the foot, but in some species they are short in front or at both ends.
Ischnochiton is the typical or central point in development of the sharp-toothed division of Chitons, around which the other genera naturally group themselves.
The great diversity in the girdle covering permits us to use that character for the foundation of a number of subgeneric and sec- tional divisions, as follows :
54 ISCHNOCHITON.
Synopsis of Subgenera and Sections. Subgenus I. STENOCHITON Ad. and Ang.
Very much elongated, valves longer than wide, roundly arched, the median valves having several slits; unibo subcentral ; girdle covered with minute, smooth imbricating scales.
Subgenus II. STENOPLAX Cpr.
Elongated, narrow, the posterior valve large, depressed, with sub- central or posterior umbo. Girdle covered with small crowded striated scales.
*
Section Stenoplax s. s. Median valves 1 slit.
Section Stenoradsia Cpr. Median valves with several slits.
Subgenus III. ISCHNOPLAX Cpr.
Elongated, narrow ; posterior valve elevated, the umbo posterior; girdle covered with very minute scales, having conspicuously larger, striated scales mingled among them.
Subgenus IV. HETEROZONA Cpr.
Shell like normal Ischnochiton. Girdle bearing small scales with large striated scales intermingled.
Subgenus V. TRACHYDERMON Cpr.
Oval ; valves having the sharp teeth of normal Ischnochiton ; eaves narrow, rarely spongy. Girdle having very small smooth scales.
tion Trachydermon s. s. Median valves having one side slit.
Section Trachyradsia Cpr. Median valves having more than one side slit.
Subgenus VI. ISCHNOCHITON (Gray) Cpr.
Oval or oblong; valves having sharp smooth teeth and solid eaves. Girdle covered with short flat, generally striated imbricating scales of moderate size.
Section Ischnochiton s. s. Central valves having one slit.
Section Radsiella Pils. Central valves having two or several slits.
I8CII\«.« mi 55
\'||. [00H2TORAIMSU Shuttles.
Shell oval, as in Isehnoehiton ; irinlle covered with .-olid, n.rivex, smooth scales, like those of Chiton 8. 8.
(ion lacJiiiui'ttdfiift s. s. Median valves having several side slits. Type £ atotro/w Sowb,
Sretioii LepidozoiKi I'ils. Median valve- having one side; .-lit. Type /. inertensii Midd.
Subgenus I. STENOCHITON Adain.s and Angas, 18f>4.
Stenochiton AD. AND ANG., P. Z. S. 1864, p. 193.
Shell very much elongated, roundly arched ; valves Ischnoid, the central valves havi ng several slits ; girdle having minute smooth imbricating scales.
This section was discarded by Carpenter, who referred its only species to his own later group Stenoradsia with doubt ; Stenochiton, however, seems to have as much individuality as most of the divis- ions of Ischnochiton, and may be allowed to stand as a subgenus.
I. JULOIDES Adams and Angas. PI. 16, figs. 6, 7, 8.
Shell much elongated, narrow, narrower in front; rufous brown, minutely spotted with white. Valves narrow, longer than wide, very convex, not carinated ; lateral margins scarcely rounded, pol- ished. Lateral areas elevated and at the margins concentrically sulcate. Girdle narrow, pale-brown, spotted with black-brown, covered with very minute, polished, imbricating scales. (Ad. and Ang.) Length 25, breadth 6 mill.
Holdfast Bay, South Australia.
Stenochiton juloides AD. AND ANG., P. Z. S. 1864, p. ?93 ; I. c. 1865, p. 58, t. 11, f. 15.— ANGAS, P. Z. S. 1865, p. 188.— " f St* adsia " juloides Ad. and Ang., CPU. MS.
This species, from its narrow, convex form and polished surface has much the general appearance of a Myriapod. (Ad. and Ang.)
This species is the type of the genus Stenochiton Adams and Angas, which is thus characterized by them: "Shell elongated, narrow, convex ; valves longer than wide, not carinated; apex of the posterior valve subcentral ; plates of insertion small, multi- fissate in the end valves, the intermediate valves having T> li- on each side; girdle covered with very minute, polished, imbrica- ting scales."
56 ISCHNOCHITON.
Carpenter gives the following notes on the type specimen : Length 22*, breadth 4 ' mill. ; shell very narrow, elongate, elevated, cylin- drical, the juguni rounded ; red-brown, narrowly streaked with paler. Posterior valve elongated, mucro median, scarcely conspic- uous, the slope behind it straight. Anterior valve forming more than a semicircle, its posterior margin (suture) emarginate. Entire surface delicately granulated in quincunx; jugal area scarcely defined ; lateral areas conspicuously elevated. Girdle inconspic- uous, covered with minute imbricating scales. Scales almost all destroyed, but looking like those of /. sanguineus, etc. Sinus large, very deep, flat, wide; sutural plates much elongated, narrow. Central valves regularly 3-slit; posterior valves about 16, anterior valves about 13 slits. The slits are irregular, sometimes bifurcating but typically rather distant. Teeth very acute, moderately long. Eaves moderate.
Subgenus II. STENOPLAX Carpenter, 1878.
= Stenoplax Cpr. -f Stenoradsia Cpr. -f- Maugerella Cpr.
Elongated, narrow Ischnoids, having the girdle covered with minute, crowded, imbricating striated scales. Median valves having the lateral areas much raised ; posterior valve large, depressed, the mucro subcentral or slightly posterior.
The subgenus Stenoplax (-f- Stenoradsia and Maugerella) has a very characteristic peculiarity. The sides and front end of the foot are so much dilated that the head of the animal is nearly or entirely concealed from below, the thin, produced, anterior end of the foot extending quite over it The gill row is shortened at both ends, reaching nearly to the head, but shortened at the tail about one- fourth the entire length of the foot. .The branchiae are largest at the middle.
STI:N< 'iM. \x divides naturally into two sections: (1) Section >plax (restricted), in which the median valves have a single >lit on each side, and (2) Section Stenoradsia, the species of which have two or several side slits in the median valves.
Section Stenoplax Cpr. (restricted).
- noplax CPU., MS. and table of Regular Chitons, 1873. — DA LI., ,U.S Nat. Mns. 1878, p. 330, type /. limaciformis Sby. This section is closely allied to Stenoradsia, the latter differing only in having several slits in the plates of the intermediate valves.
ISCHHOCHITOH.
I. I.IMA< ll'oKMI- Si.wrrhy. PI. Hi, fi.LTS. •' I'J.
Shell rl.m'jaled and narrow, elevated, well areh. d : bull irreriiish, indistinctly marldrd with darker, and occasionally blotehed with red; longitudinally costulate, not graiiosc ; <_rirdl<
minute.
The sculpture upon the central areas con>ists of line, close, smooth lon-itudinal rildets; these continue upon the lateral areas, becom- ing broader and Hat there, and being decidedly waved or irregular on the slope between central and lateral areas. The end valves are sculptured with close, flattened concentric ridges, which are more or less wavy or irregular. The lateral areas are well raised, and are separated by a considerable space at the jugum. The mucro is subcentral and low.
Interior stained with bright pink and blue-green ; sutural plates well developed ; sinus flat, angular, wide; anterior valves with 11, central valves 1, posterior valves 9 slits. Teeth sharp, smooth ; eaves grayish, solid.
Girdle covered with extremely minute subequal scales.
Length 35, breadth 12 mill.
Length 25, breadth 10 mill.
Florida Keys ; St. Thomas, St. Vincent and West Indies gener- ally; Central America and Peru; under stones at low water.
Chiton, limaciformis SOWERBY, P. Z. S. 1832, p. 26; Conchol. Illustr. f. 38. — KEEVE, Conch. Icon. t. 8, f. 42. — Ischnochiton ciformis SHUTTLEW, Bern. Mittheil. 1853, p. 190. — (Stenoplax) limaciformis Sowb., CPR. MS., and DALL, Blake Gas- trop. p. 415. — Ischnochiton multico status Ad., DALL, Proc. U. S. Xat. Mus. vi, p. 337, 1883, not of C. B. Adams. — Chiton prodwhi* Ilr.KVE, Conch. Icon. t. 17, f. 97, 1847. — Chiton sanguineus Ki i:\ i:, /. c. f. 98. — f Lepidopleurus sanguineus CPR., Ma/. ( 'atal. p. 1(.>4.
The West Indian specimens collected by Robert Swift at St. Thomas, and the Peruvian specimens which I have examined are absolutely identical in character except that the former are finely mottled with pink, and one specimen is heavily blotched with crim- son on the second and tail valves (fig. 9). Another tray from the Swift collection contains pale but!' examples with faint darker markings. Carpenter has reported the same species, or one very closely allied, from Ma/at Ian and from Japan. The last certainly requires confirmation.
58 ISCHNOCHITON.
The characteristic mark of this species is the sculpture of the lateral areas and end valves, which are non-granulated but have slightly serrated concentric flat riblets. The girdle scales are flat, solid, not striated or very obsoletely so, and far more minute than in /. n /ut n.-:
I. FLORIDANUS Pilsbry, n. sp. PI. 17, figs. 19-22.
Shell elongated, narrow, elevated, the valves roundly arched, not carinated. Color whitish or delicate green, variously marked and mottled with olive, blackish-olive or gray.
The lateral areas are raised, longitudinally costulate, the riblets cut into granules by radiating impressed or incised lines devel- oped over the whole area or over the forward half of it. End valves similarly cut into granules by radiating and concentric lines. Cen- tral areas covered with longitudinal riblets which are finer and closer upon the jugum, usually showing a tendency to be a little irregular on either side of it, and are granulous toward the outer angles of the areas. Posterior valve large, rather depressed, the mucro slightly posterior.
Interior pink, blue and white, in various proportions, rarely all roseate or all white. Sutural plates strongly developed, rounded ; sinus wide, deep, square. Anterior valve having 9, central valves 1, posterior 9 slits; teeth sharp, smooth or very obsoletely lobed. Eaves narrow, solid.
Girdle delicately marbled with bluish and gray, densely clothed with rounded, solid, delicately striated scales.
Length 41, breadth 15 mill.
Length 35, breadth 1U mill.
Key West, Florida. (Hemphill.)
This species is allied to J. limaciformis, differing in the differently sculptured lateral areas. It is also related to C. purpurascens C. B. Ad., but differs in several respects, notably in the flatter poste- rior valve and longer central valves.
I. i-L'RPURASCENS C. B. Adams. PI. 17, figs. 23, 24.
Shell <-l<>iiLrat<Ml, narrow, much elevated, the lateral slopes of the valves nearly straight, dorsal ridge roundly subangular. Generally pale buff, marbled with olive or mottled with black, and having red patches along the dorsal ridge. The lateral areas are raised and longitudinally ribbed, the riblets cut into granules by radiating impressed lines; end valves cut into coarse granules by radiating
m IIN<>< mi 59
and (M.ncciitfic lines. Central areas having tin- dorsal ridi"
or only minutely punehired ; the longitudinal riUets of the lateral
area- extend forward Upon the "pleura" or lidet "| tbc e.-ntral
areas. Posterior valve elevated, the IMIICTO .slightly posterior,
elevated.
Interior white or stained ; sutural plates short; sinus wide, tlat. Anterior valve having 10, central valves 1, posterior valve ID -lii~. Teeth sharp, smooth. Eaves narrow.
Girdle rather wide, alternately bluish and buff, densely clothed with minute, solid, striated scales. Length 16, breadth 7 mill.
Jamaica (Adams) ; Key West, Florida (Hernphill ; Rush.)
Chiton ]>iii-]>iir<i8cens C. B. ADAMS, Proc. Boat. Soc. N. II. ii, p. 9,1845. — Ischnochiton purpurascens Ad., DALL, Bull. I. S. Nat. Mils'. No. 37, p. 172,
Adams' description is as follows : Shell much elongated, purplish- ruddy, concentrically striated ; margin wide, very minutely scaly, bluish, alternately paler. Length I'l, breadth '5 inch.
This species differs from /. floridanus in having all of the valve- decidedly shorter and broader ; the posterior valve much more elevated, the jugum almost smooth. It differs from /. lirnaciformis in having the lateral areas and end valves conspicuously granulose, etc.
In this species the valves are almost as short as in the typical Ischnochitons, but the sculpture is quite that of Stenoplax. The mucro is more raised than in any other described Stenoplax. The species is abundant at Key West.
The color-pattern is excessively variable.
I. FALLAX Carpenter, n. sp. PI. 16, figs. 17, 18.
Almost exactly like Ischnochiton magdalenensis in form and sculp- ture, but more roseate ; the central areas pitted ; lateral areas having close radiating wrinkles interrupted by lines of growth. Interior: Posterior valves having 9, central 1, anterior 10 slits; teeth acute ; eaves conspicuous ; sinus moderate, scarcely laminate, but the jugal part of the valves produced forward. Girdle having very minute granules.
Length 27£, breadth 12* mill. ; divergence 120°.
Monterey, California.
The color is either entirely reddish-ilesliy or clouded and dotted with olive and whitish. The main distinction between this form
60 ISCHNOCHITON.
and /. magdalenensis is that the latter lias radsioid valves and coarser girdle scales. ( 'arpenter's description is given above, and the fig- ures represent the type specimen.
The foot is produced forward, and the gill row is short at both
I. A i. ATCS Sowerby. PI. 16, figs. 1-5.
Shell much elongated, narrow, elevated, rather thin. On a light Mi-shy hut!' or greenish ground it is delicately marbled and mottled with olive or olive-green. The sculpture consists of longitudinal close, narrow ridges, which are finer on the dorsal ridge, and clump to an irregular granulation on the lateral areas and terminal valves. The lateral areas are decidedly raised ; the jugal area is divided from the pleura by a change in sculpture, which becomes coarser and more or less divaricating, sometimes forming a cellular pattern at the edges of the jugal area and on the slopes of the lateral areas.
Interior rose-pink, rarely almost white; anterior valve having 9, central 1, posterior valve 9 slits. Teeth sharp, eaves moderate, solid. Sutural plates large, rounded ; sinus very deep, narrow.
<iirdle wide, thin, covered with fine, even, short, striated solid scales,
L.-ngth 57, breadth 16 mill.
Length 40, breadth 16 mill.
Islands of Siquijor and Zebu, Philippines, under stones at low water.
Chiton alatus SOWERBY, P. Z. S. 1841, p. 61.— RVE, Conch. Icon. t. 8, f. 45.—Is«hnochiton alatus GRAY, P. Z. S. 1847, p. 127, and /. n/tu8 Gray, Guide, p. 1 82.— Stenoplax alata CPR. MS.
The solid, deeply striated scales of the girdle are very character- i-tic, as is also the sculpture. The pattern of color is an indefinite and variable mottling. Figures 3, 4, 5 are drawn from a typical specimen received from Sowerby. Figures 1, 2 are from draw- ing made for Carpenter, and represent the scales as much more elongated, and the head valve as less emarginate. 1 am disposed to believe that this last peculiarity is a mistake.
The sole is produced forwa rd as far as the month; head Me>hy : veil copious, neck lappets long. Gills about one valve's luvadth removed from neck and the same at tail. Vent inconspicuous. Foot fleshy, projecting.
[01 ll\... ill i ,
1 ferpeoter, 1*7*.
, i/\. mid tahl.- of i;«- ci.it :
Proc. r. s. N:,t. M.IS. I.STS, P. 830, type G maj B
—M<tu<i<-,;ii« c\'\i. .J/x. and table of Reg. Chi'toof, type .i/
Cpr. .l/.S'.— Iwhnortnltin (in pan . SIM i i i.i.u .. I '„ m. Mill heil. ! p. 86,
Like Stenoplax, hut intermediate ralvee 1 1 aving several rid The Uadsioid valves alone di.-iin_iruisli tliis from Stenoplax. Its relations \\itli the Australian Stenochiton. jntuid<'» an; jirolmlily not especially close.
In one species, /. conspicuus, the mantle scales have Ixrn ti formed into slicrt, round, striated bristles, and on account oftlii- modification Carpenter established for it a subgenus under Chceto- jt /en rn which he called Maugcrella. We are com pel led to.-nppr«-.- thi* group because of the excessively close relationship <-xi.-tinir lM-t\\«-«-n /. conspicHitx and the two species of genuine Sten- and /. magdalenensis.
I. ACRIOR Carpenter, n. sp. PL 14, figs. 86-89.
Shell much like /. magdalenensis, but broader and flatter, with much sharper sculpture. Olive-green, pink where worn, or > times light flesh-colored, with the jugum or central areas often green. Girdle dark ashen or olive.
The anterior valve is notably concave, as in /. conspicuus. Tin- lateral areas are much raised, and sculptured with acute radiating riblets, sometimes splitting; central areas having acute longitudinal riblets.
Interior pink, with a blue spot at the jugal sinus. Sutural p! wide, pink; sinus broad, deep, angular. Anterior valves having 13-15, central valves 2-4, posterior valves 10-13 slits. Teeth long, sharp, smooth. Eaves wide, dark-blue.
Girdle wide, tough, covered with very small, solid, shot
Length 110, breadth 55 mill.
Length 75, breadth 40 mill.
Cerros (Cedros) Island to Cape St. Limn.*, Lower California,
StenoradsiaacriorCpR.MS. — Chiton iintfjd'i/eneimiin part Ki i Conch. Icon. t. 4, f. 20a, not of Hinds.
This species represents one extreme of variation of the / magdalenensis type, the other extreme being 7. con^»icun.<. 1 i
62 ISCIINOCHITON.
still to see specimens truly ronnoctinir the three forms, although they arc doubtless closely allied. The present form differs from }n>igd'ilenen*is in having a concave head valve, strong, distinct, acute riblets upon the central areas, and a generally more robust A th.
/. t '•« also has a concave head valve, but the sides of tin-
central areas show no sculpture except microscopic granulation, and the scales of the girdle are pulled out into true spines or bris- tles.
There is a light form of acrior which is fleshy-white, the girdle gray-white or dark ; and some of these have the jugum or the cen- tral areas of the normal green-olive color (fig. 89.)
1. M A.-I.AI KNKNSIS Hinds. PI. 15, figs. 98, 99, 100.
Shell elongated, rather narrow, generally faintly mottled with delicate olive on a light greenish, blue or pinkish ground. Interior bluish, white or pink. Lateral areas and end valves having radia- ting riblets, central areas finely pitted.
The lateral areas are distinctly raised, radiately delicately ribbed. Front slope of the anterior valve straight. Central areas having a more or less developed system of branching reticulating wrinkles pro- ilncnig oblong or diamond- shaped pits. Umbo of posterior valve central, but little projecting.
Interior : Sutural plates well developed, the sinus deep, angular. Anterior valve having 10-13, central valve 2-4, posterior valve 10-12 slits.
Girdle having fine, close, solid imbricating scales.
Length 75, breadth 30 mill. ; divergence about 130°.
Length 55, breadth 27 mill.
Monterey, California, south to Magdalena Bay; Catalina and Sta. Barbara Is.
Chiton magdalenensis HINDS, Zool. Voy. 'Sulphur' ii, p. 54, t. 1 :». t. 1 . REEVE, Conch. Icon. t. 5, f. 20b. — Stenoradsia magdalen- ensis CPR. — S. "magdalensis" Ki;i:r, West Coast Shells, p. 107, f. 94, and of collectors generally.
This species differs from /. conspicuus in its pitted instead of finely granulose central areas and in the mantle-covering of minute, solid scales, unlike the short spines of the other form. It differs from 7. • /• in the much finer sculpture and more delicate coloring.
rSOHNOCHT] »'».'!
Tin- loot projects foruard, conceal! MI: tin- lim.j tV-.m bttN :itli.
I. . 02XBPX4 GUfl Carpenter, n. ip, I'i
Shell lar^e, elongated. moderately elevated; greei
earthy-brown ), luit \\ lien- eroded at tin- heaks it i^ pink. In! pink, witli a blue spot at tin- juiral -inn-. Lateral an-as much raised, having acute radiating rilil. : enlly *mnnih, but microscopically -rauulated, BOtQetitiK
faint longitudinal strice at the jogum, Front */ope of th<
i'<i /re en/icdi'f ; yirdle densely beset with short bristles, <, <> vet-
1'i'tll nfJiCrt.
The entire surface is very densely miero-eopieally granulated, where not eroded. The lateral areas have fine aeute radii and often the back edge of each valve is crenulated by oblique, sharp, little folds. The color is often varied by darker little flame- on tin- central areas. The posterior valve is large and depressed.
The sutural plates are large, the sinus deep and angular. Inser- tion plates having in anterior valve 9, central valves 2 or 3, j> rior valve 10 slits. Teeth sharp and thin in posterior and central valves, but blunt and bi- or trilobed in anterior valve. Eaves wide. solid, light blue-green colored.
Length 82, breadth 36 mill.
Length 89, breadth 41 mill.
Santa Barbara, California, t<> Magdalena Bay.
Maugerella conspicua CPR. MS. — OROUTT, Proc. U. S. Nat. Mu>. 1885, p. 544.
This species may be separated from /. amor by its unsculptund central areas and velvety rather than scaly girdle. It is more closely allied to I. magdalenensis and may, indeed, prove tointergrade with that species; but in magdalenensis the front valve is scar concave in front, the sides of the central areas have a honeycomb sculpture, and the girdle is very finely sc<ilij, not re I ret;/.
A specimen before me from Magdalena Bay is ferruginous brown, the central areas are more rugose, and the -i/. i- unalfer, length 45, breadth 20 mill. Another specimen has the central areas sculptured like /. acrior, but less strongly; the Birdie being bristly, however, as in typical eow.<;m-H"-<. S:m Diego may be regarded as the center of distribution of this
rpenter ha- i:ivn a varietal mum- to a broad, worn specimen, which he thus describes :
Var. solidus (pi. 15, fig. 97). Very solid, wide, ashen; inside whitish, the posterior valve with 10, central valve 2-3, anterior valve 12 slits. Length 72, breadth 40, divergence 130°.
Carj» at* /•/»/, near Sta. Barbara, California.
This is scarcely more than an individual variation. The figure ivpn-mts the valves only of the type specimen. The mantle is normal. The sculpture is worn away except at the edge. It has evidently lived in a very exposed situation.
Suhgenus III. ISCHNOPLAX Carpenter.
LchnnjJ,i.r('i-ii. (Table of Reg. Chit. 1873), DALL, Proc. U. S. Mus. 1878, p. 330, type C. pectinatus Sowb.
Body elongated, elevated, the valves having high suttirM plates ami strongly elevated lateral areas; mucro posterior, elevated; girdle clothed with very minute imbricating scales and having larger conspicuous striated scales scattered among them.
The girdle is like that of Heterozona, but the valves and general shape are similar to Stenoplax, except that the mucro is posterior and elevated, a character recalling Callistockiton.
I. i IX-TINATUS Sowerby. PL 17, figs. 25-30.
Shell elongated, narrow, elevated ; gray, mottled and dotted all over with black, more or less stained in places with pink.
The valves are strongly convex ; end valves radiately coarsely granose-ribbed ; umbo of posterior valve elevated, situated behiu<! the center. Lateral area much raised, having radiating granose riblets ; central areas having smaller cords, which are close and lon- gitudinal on the jugum, but become more spaced, coarser, and [liny on the pleura or sides of the central areas.
Interior bright pink. Anterior valve with in- 12, intermediate valve 1, posterior valve 8-11 slits. Teeth sharp, frequently bifid ; eaves unusually wide, solid, scalloped by the sculpture of the out- side. Sut u nil plates high, rounded. Sinus deep, square.
Girdle (pi. 1 7, figs. 28, 29) covered with extremely fine scales among which larger, long fiat scales are irregularly scattered.
Length 36, breadth 16 mill.
Length 40, breadth 17 mill.
Cuba (Cuming) ; Guadeloupe (Swift) ; Barbados (Rush).
DBOHVO4 HI i'
Chifnn /><><•( in, it //.< S«,\\ I ;.. M a-. , ,f N ill . I I i~f ., .lime. |S-lU. p. : ' t. 1C., t'. :i ; Conch. Illustr. ('. 1 1C,. |;, ., \ , . ( ',,, ,,.),. I
1 83, ' '• /-•'•hnn.'hitiiii i pectinatu* SIM n u.\\ ., Hem. Mitthdl. I
|t. 77. — •I.tf'hnniilii.r }irrtiu'lfu.i CPB., M>. — Chiton ncnti/i,
KI:I;\I:, Condi. Icon. t. *, f. Mt.--Chitnn miill'u-n*tuhi# ('. \\. Ah.,
Proo, r.«.st. Boo, N. II. ii, |». 8, !
LVadily known from other \Ve>l India ( 'hitons liv its dong r.inn, speckled and mottled coloring, SUM! especially \>\- the peculiar ^irdlo. The larirf scales are distinctly but finely Mriated. The grOUnd-Oolor of the girdle is pale bufl', with patches of olive- ii'reen. The larLie scales are mingled white and buff on the liirlit tracts, and are a dark blue-green on the dark patches.
Reeve's C. acutiliratm (fig. 30) is a typical pcH'n,<ihi.<. \ have not seen the Ch.multicostatus of C. B. Ad., described from .Iain; and the description is too meager to permit certainty in referring it here.
Subgenus IV. HETEROZONA Carpenter, 1878.
Heterozona CPR. (Table of Regular Chitons, 1 873), DALL, Proc. T. S. Nat. Mus. 1878, p. 331. Type H. cariosa Cpr. MS.
Shell like normal Ischnochiton ; girdle bearing small scales with large striated scales intermingled.
The girdle is that of Ischnoplax, but the shell is not elongated, and the umbo of the posterior valve is median, not posterior. The arrangement of scales normal in this section is the same as a patho- logic condition sometimes met with in individuals of species normally having regular and equal scales, but in which the girdle has been injured; the injury being repaired with scales much smaller than those upon the healthy portions of the girdle.
I. CARIOSUS Carpenter, n. sp. PI. 24, figs. 20, 21, *2'2.
Shell oblong, rather elevated, the valves broadly arched and rounded dorsally. Color, soiled yellowish, unieolored or with indistinct brown spots.
The lateral areas are raised, and sculptured with a var\ in- num- ber (about 7) of radial ribs, which are irregular, often splitting. and very unevenly granose. Central areas finely granulated upon the dorsal ridge, the granulation giving place on the side-slopes to a rather strong but fine corrugation ; the wrinkles longitudinal, but converging forward toward the middle: and minutely irregular 5
or undulatiDg. Toward the outer edges the wrinkles become ler and more separated. End valves sculptured with radiating riblet> : posterior valve having the macro central. Interior white, the end valves usually marked with a brown crescent; sutural lobes rounded ; sinus wide and flat. Anterior valve having 12, median valves 1, posterior valve 12 slits; teeth smooth, rather .-harp. Kaves solid.
(iirdle covered with flattened striated scales, which are verv unequal in si/.c, but become larger toward the valves (fig. 21).
Length 32, breadth HI mill.
Australia,
The texture of the shell is peculiar, the outer layer being thin and easily broken through, exposing an extremely spongy layer. ( arpenter's specimens seem to have been worn so as to expose this layer in places, hence the name cariosus. In the normal and un- worn specimens before me the outer surfare is scarcely carious though dull and uneven, nor are the eaves spongy. Carpenter's original description is as follows:
Heterozona cariosa (pi. 24, fig. 23). Shell subelongate, rather elevated, the jugum rounded. Mucro median, moderately elevated ; whitish-ashen, slightly variegated at the sutures occasionally. Central areas very granose in a young specimen, the granules minute and close toward the jugum, then becoming rugose lines, undulating anteriorly, and widely separated on thesides; the adult shell is carious. Lateral areas having 3-8 deeply but irregularly granose radii, the grains at the sutures large; end valves having 30-40 graniferous radii. Interior: posterior valve with 11, central 1, anterior valve 11 slits. Teeth acute; eaves wide, spongy; sinus large, flat, smooth. Girdle (pi. 24, fig. 23), clothed with nornal striated imbricating scales and having long, large striated solid scales scattered here and there. (Qt?r.)
Length 30, breadth 161 mill., divergence 100°.
Australia (Mus. Cuming No. 46).
This shell forms an exact transition between Ischnoplax and the true Ischnoehiton. The mantle resembles Ischnoplax in its double series of scales ; although if the large ones were plucked out, the latter would be nearly of a normal arrangement, except that they aiv rather nariow a- in /. castns. It differs from 7>r///>oy,A/.r, not only in not lu-in^ narrow and elongated, but in having a normal IIMKTO. The species is curiously like Stciiormltn'n magdalenentis,
HNO in i'
younir, ill .-hape :in<l plan of .-ruljil HIT, l»ut the Scales :i and the central valves have only OIK- .-lit. ' Carpentrr'- .!> -eripljnii an<l Bgtm dill! r SMI:
specimens before me, described ahove. li' the Ian
cally distinct it may he called /. Bttbcaric
Siihgrnus \' . Ti: ACII YI>I:I:M<>\ ( 'arpenter, 1863.
., Kep. l',rit. &MO. Adv. Sri. L863, p, G. O. SABS, Moll. lie-. A ret. Norv. p. 1 i IVmi. - - cinereus L.). — Boreochiton S\i;- in ; p. lit! (proposed for C. ruber Lowe and C. marmoreiu Fahr.;. — (liitoii, Lepidoplewrus, Leptochiton, Ischnochitnn and /,'>/>//>//•" • •!' various authors.
Valves exactly like those of Ischnochifou, hoth diitside and within: girdle having the scales very small, close and sim...tli. (Jills from one-half to over three-fourths the length of the ;
This irroup was originally proposed as a suhgenusof I.«r]nnn-1, and the following species referred to it: refij><>r<>.<n.-< Cp stinctus Old., trifidus Cpr., dentiens Old., gothicus Cpr., h<irt> (1pi-., unltxUii Cpr., flectens Cpr. Carpenter subsequently stated that Trac.hydermon was equivalent to Gray's second section of Ischnoehiton, " ** scales of mantle minute, granule-like." (1*. /. S. 1847, p. 127), this section containing only the species P. >//'//•'/'/'- »////x C. cinereus L. and Lowe. Still later, Carpenter raised the group to the rank of a genus, adding to his diagnosis the words "gill- short." It is evident that a type species for the group should be selected from Carpenter's original list; not from among the species si; quently referred to the group by him. The shortness of the Drills influenced Carpenter and Dall to place this group next t«> the Leptochitons, but there is probably no affinity indicated l>y this character, Trachydermon being phy to genetically as far from 7. ffi iton as Ischnoehiton is.
The length of the gill-row is so variable that genera cann« founded upon that character in the present family. In the species itllms and ruber I have ascertained the gills to l>e median, as they are said to be also in the tcrobieukUvs and //» of Midd. In the other species which I have examined, or upon which data are available, interstinrtii.-*. 0 the irills
extend from two-thirds to over three-fourths the length <»t' th.
68 IM IIN<»< IIIToN.
It is therefore obvious that n<> separation can he made from other suhueiiera of hchnochiton on this character.
Several species of Trachydermon liave distinctly spon_ like tlinse of T"/tir>//*i. This structure is exceptional in 7.W/M*- chiton where the eavee a- a rule, aie solid, as in the genus Cluito- i. The fact i>e that certain forms of Trachyderinon,
such a< T. ruber, form a partial transition from hchnochiton to
• /A/.
From ZVoMyrfermon, Carpenter has sundered a few species hav- ing Kadsioiil central valves, to which he has given the sectional
name Ti: \< H \n\ i»i \.
Section Trachydermon, s. sir.
I. CINEREU8 Linn.'. PI. <i, figs. 25-31.
Shell oblong, elevated, the dorsal ridge subangular. Anterior valve half-circular, the posterior margin decidedly emarginate. Very evenly and finely sculptured with diamond-shaped granules, which, although somewhat irregular, seem to be formed by the <»l)li(jue intersection of curved incised lines radiating in two direc- tions from the apex. Intermediate valves having precisely the same sculpture upon both central and lateral areas, the latter slightly raised, but not distinctly separated from the central areas. The posterior margin of the intermediate valves is rather produced or beaked in the middle. Posterior valve decidedly smaller than the anterior, having the umbo low, inconspicuous, and somewhat anterior.
Interior whitish or brown-tinged; sutural plates wide; sinus narrow.
Insertion plates nearly smooth, slightly roughened «nit>i«le. Number of slits in the anterior valve 9 or 10; in the posterior valve 10 or 14J. The teeth of the posterior valve are rugose. The intermediate valves have a single slit on each side.
lor varying greatly, the most common pattern being a.-hcn thickly mottled and blotched with olive ; others are a li.irht fleshy- oranire. and frequently the light and dark patterns are combined on ;irioiis valve- of one individual.
The girdle has usually alternating light and dark bars. It 1 with minute >e;il.-s th«- edge having a fringe of delicate v .-pines.
II No. I II TON.
r_' ', l.ivadtli 74 mill. Leii-th IS. luvadih ID' mill. liritlnh mid Scandinavian iSV./x. m//-//» /" /,».//•/, •//. XO///A /o /;
/\ • /
Chiton etfMTtffll LlN* N'at. xii, /rx/r Hanky.
Conch. ]>. 17.- -Low i-:, /«>nl. .Joimi. ii, p. 9 II \NI.KY, Hist. r.i'il. Moll, ii, |>. -ID'J, (. .V\ f. 1, (T. ni'iryiifif' plate*.— r. Hinryhntln* IV.N \.\ M, P.rit. /ool. iv, p. 71. t. ::•;, f. 2, and of MONT., Sown., IJ\ i:. and .1 1:1 i 1:1 IB, Brft ( kmch, iii, p. 2'Jl , t. 56, i'. 5j P. /. S. ISS'J, p. 669.— C. marginatus M; Moiuis, Knuna der Kieler Bucht, ii, t. 1, f. 1-5. — Craspedoch'ln* ma ryln.it u« SARS, Moll. Arct. Norv. ]>. 11"), t. 20, f. 16 ; t. 2, f. L'.— Trachydermon mt try hiatus CPR., New Eng. Chitons, p. 1 Trachijdermon. cinereus CPR. MS. p. 15. — DAM., Proc. I Mus. 1878, p. 323. — NOT Lepidopleurus cinereus SARS, /. r., t. 7. t'. 8. — Chiton, circmnrulliitit.* Hi;i:vi:, Conch. Icon. t. 27, f. K
This species may be known by the evenly shairreened surtin-r. which is quite different from other North Atlantic Trachydermons. Tr. dentiens Gld., which Jeffreys considers the same as Hnereiift, differs in sculpture, color, and the shorter form. There are a num- ber of old and more or less doubtful synonyms, such as Ch. fiiscatus Brown, 111. Conch. G. B. p. 66, t. 21, f. 17 ; and Jeffreys quotes also cimex Chemn. and cimicinus Landt.
Carpenter seems to have supposed that the gills of this species did not extend forward beyond the middle of the foot, but I have determined by the examination of alcoholic specimens, one of which is drawn on pi. 7, fig. 57, that they extend nearly to the head, being composed of 16 or 17 plumes on each side. They are also so figured by Meyer & Mobius. In this character, cinereiu di from albus and ruber, in which species the gills are median.
Carpenter, having examined the type of C. circumra/lnf writes that he is satisfied that it is merely a cinereus. The locality given by Reeve is no doubt wrong.
Yar. variegatus Phil. PI. 7, figs. 58, 59, 60.
Smaller, with triangular sutural laniinir. Anterior valve having 8 or 9, posterior valve having 7 or 8 slits in the insertion plates. Length 8, breadth 5, alt. 3 mill.
Mediterraii( ^
70 I-< IINnrnITOX.
variegaku run.., Knum. Moll. Sicil. i, p. 107, 1836; ii, p. 83, t. 19, f. l:>.— WKINKAUFF, Conchyl. des Mittelm. ii, p. 4lL>.— I — i i., Chit. del mare di Geneva, Bull. Mai. Ital. iii, p. 7, t. 1, f. 1, 1870. — Chiton mnrginatus Penn., TIBERI, Bull. Soc. Mai. Ital. iii, p. 139, 154. — MONTEROSATO, Enum. e Synon. p. 16, 1878. — Brn., DAI i/ iV DOLLF., .M..11. Mar. Rouss. i, p. 497, t. 61, f. 13-Ki; t. 62, :
I have preferred to retain the Mediterranean form distinct, at least as a geographic variety, for it differs from Tr. cinereus of the north in being constantly smaller, having fewer slits in the end valves, and having the sutural plates of a decidedly different shape.
I. Ai.r.rs Limn'. PI. 7, figs. 35-38.
Shell oblong, elevated, the back keeled, lateral slopes nearly straight. Anterior valve half-circular, its posterior margin slightly concave ; sculpture consisting of some scarcely perceptible, low radiating ridges, often wholly obsolete, and an excessively minute shagreening or granulation of the whole surface, the granules showing a disposition to be arranged in oblique curved lines. Intermediate valves slightly beaked, produced forward in the mid- dle, having the same sculpture, and showing low, irregular growth wrinkles. Lateral areas scarcely raised, sculptured like the front valve. Posterior valve having the umbo slightly elevated, central, inclined backward.
Interior white. Sutural plates large and wide, extending from the insertion plates nearly to the jugum. Sinus rounded.
The anterior valve has 13 slits in the smooth and rather sharp insertion plate; the intermediate valves have one slit; the posterior valve has 10 slits, and the edge of the plate is decidedly roughened and irregular. Another specimen has 14 slits in the anterior valve, }'2 in posterior valve; and in still another individual, some of the intermediate valves have two slits on one side.
The girdle is covered with small gravelly scales, and has no marginal fringe of long scales or spines.
The gills consist of thirteen leaflets on each side, extending for- ward two- thirds the entire length of the foot.
The color is a very delicate buff tint, sometimes almost white, often shading into a light orange on the posterior part and lateral areas of each valve. Most specimens have more or less of a blark deposit on the back part of the valves.
Length 1."), breadth 7 mill.
Length 10, breadth 5-6 mill.
»CHNOCHIT<
A relic <nnl .\nrlli At/anlir Sects ; Grccn/n n<l ; /r/7////// tn'i'i/rii ; Xnimlimn'iii ; />'/•// /W/ n{ .}/,,,,
S/. Lawrence, Maine, and south to Mauaehutettt \
In tlir r,icifii- from Arctic Ocean, xo /f///. In tin- .S'/M/w////// /..-., n'ent to h'l/xkn. Low water to :!:;7 f'ms.
Chiton ulbii* LINM:, Syst. Nat. xii, p. 1 107.- Lowi:, /•>«.]. .I.-urn. iii. p. SO.— Sown., Conch. III. f. !>'.), UK).- GOULD, Inv. Rfa loi). f. 21.— MlDD., Mai. Ross, i, p. 120.— I-'OKI:I.< A- HANI i;v, I'.rit. Moll, ii, p. 405, t. 62, f. 2.— STIMPSON, Sh. of N. En#l. p, inv. of (Jrand Manan p. 2'J. — .Ji:i'F., Brit. Conch, iii, p. L'-jn ; v. p. 199, t. 56, f. 3.— BINNEY, in Gould's Invert. Mass. p. 265, i. 51 ? Chiton onjzn S]-I:N,;IJ:K, Skrift. Nat. Selsk. iv, hft. 1, 17'.»7, teste JiflV. — Ch. «selloides LOWE, Zool. Journ. ii, p. !().'», t. ">, f. 3. — WOOD, In<lcx Test., Suppl., t. 1, f. 9. — Ch. sagrinatus Connorv, Amer. Journ. Sci. xxxiv, p. 217, 1838; Bost. Journ. ii, p. 82. — Lejttochiton albus H. & A. AD., Gen. Rec. Moll, i, p. 473. — Chitmi (Lepidopleurus) albus JEFFREYS Brit. Conch, iii, p. 210. — Ch. (Lophyrus] albus JEFFR. P. Z. S. 1882, p. 669. — Lophyrus fi/lm* SARS, Moll. Reg. Arct. Norv. p. 114, t. 8, f. 2 (? not t. I, f. 9).— ? Ch. minimus GMEL., Syst. Nat. xiii, p. 3205. — Trachydermon albas CARPENTER, New Engl. Chitons, Bull. Essex Inst. v. p. 153; MS. p. 15.— DALL, Proc. U. S. Nat. Mus. 1878, p. 322.
This well known Arctic and subarctic species is intermediate between Tr. cinereus and Tr. ruber in sculpture. The granulation is much finer than in the former of these, but is on the same general plan.
On pi. 6, figs. 32-34, is copied a Carpenterian drawing of the interior of Tr. albus. It is, however, incorrect, the form of head and tail valves being unusual, and the slits of the latter entirely incorrect. The central valve is well represented however. The tail valve of a specimen from Grand Manan, drawn by the writer, is shown in fig. 38 of plate 7, correctly delineating the slits.
I. EXARATUS Sars. PL 7, figs. 39-49.
Elongated, oblong-elliptical, strongly convex : valves distinctly obtusely carinated medially. Anterior valve nearly semicircular in front; the posterior edge forming an obtuse reentrant angle, with a rounded notch in the middle; surface di.-tinrtly, radially grooved with single rows of rounded granules between the grooves, becoming larger toward the margin.
, '2 I»CIIN«)CHIT('N.
Median valves are moderately wide, nearly straight posteriorly, tin- hinder ones with a slight median beak with distinct diagonal furrows and ridges, dividing them into median and lateral areas; the median areas are covered, on the sides, with fine but very distinct longitudinal grooves, with the intervening ridges narrow and rounded, more or less confluent and broken up into granules, near the diagonal lines towards the median ridge becoming finer and irregular, and finely granulous anteriorly and along the carina. Tin- lateral areas are more elevated and covered with stronger radiating ridges, broken up into oblong and rounded, flattened granules, and separated by narrow radial furrows. The lateral insert ion-plates of the median valves project but little beyond the upper lamina; they are sub-truncate, with a thin notch or slit cor- responding to the diagonal line above. The posterior valve is transversely elliptical, with the posterior edge evenly rounded ; the front area is as in the preceding ones; the posterior area is covered with fine radial and concentric grooves, dividing it into radiating rows of small rounded granules; the articulating plates of its front edge are rather wide, broadly rounded or sub-truncate, and separatee! l>v a broad, rounded median sinus ; posteriorly the inner surface is marked by about sixteen radiating lines, terminating in thin notches of the inserted edge, which is very narrow and simple.
The marginal membrane is rather narrow and covered with rather stout, prominent, oblong and obtuse spinules, regularly arranged in quincunx, their ends looking like granules, at the edge and on the lower side these are replaced by small slender spinules.
Head rounded ; hood large, the sides produced backward into rounded lobes. Foot long and rather narrow. Gills about twenty- four on each side, extending from the posterior end of the foot to about its anterior third.
Length, 17 mm.; breadth, 8 mm.; height, 5.5 mm.; length of shell, 1 .")..", nun.; breadth, 7 mm.; length 1st valve, 3 mm.; breadth. (5 mm.: ]"ii_rth .'Ird valve, exposed part, 2 mm.; breadth, 7 mm., length of p -terior valve, 3.5 mm.; breadth, <! mm. ( }'crr!ll.)
Xnrway; Off Martha's Vineyard, 101-194 fms.; off /V/-//<///r//,/,/, Flo.
/,<//,//_»//•//.< r.nirntu* SAKS, Moll. Keg. Arct. Norv. p. 11.°), t, 8, f. 1 ; t. II, f. 1, 1*78. — Trachydermon exanihi.* Sars. VKKIIII.L. Anier. Joom, Bel xxiv. p. :;i)f>, 1882; Trans. Conn. Aead. S-i. vi, p. 208,
UN.., Bin
t. :',(>, f.2, 2a,2&.- DM. i, Hull. [ . B, Nai. f. 1'.
This species is readily di>t inurnMied from I \ the
very di-tinct differentiation of the valves into median and in
areas, having lines of sculpture rniiiiin.Lr in diH'en-nt direction-, and by (lie much coarser granulation of their Bdlfaoet, In I. there are no distinct lateral area-; the radiatiirj grooves JIIM| ridge* arc absent ; and the granulation is >o line and ub-mn- a.- ; scarcely visible without a lens. Tlie spinulation of the mar: membrane is similar in the two species. ( Verrill.)
I. DENTIKNS (Jould. PI. 8, figS. 61-()~>.
Shell oval, rather elevated, dorsally angled, ash colored, clon -ly and finely mottled with olive, and having a series of alternat in ir olive and light spots upon the back edges of the valves ah.ni: the sutures. These spots are often obscure or wanting, and in some specimens the ground color is a pale orange-flesh tint.
The valves are covered with a very minute sharp granulation. the granules small but well raised, and on the central areas of some specimens they are somewhat disposed to be arranged in longitud- inal lines converging toward the dorsal ridge, this disposition n-u- ally stronger toward the lateral extremities of the valves. Tin- lateral areas are a little raised, the diagonal lines separating them from the central areas rather distinct. The urn bo of the posterior valve is median, somewhat raised, the slope behind it being depressed and concave.
The interior is either whitish stained with gray-green, or quite green. The sutural plates do not project as far as usual, and on some valves they are emarginate in front. The ju.iral sinus is wide. angular, flat or encroached upon by the jugum. The anterior valve has 11 slits in the insertion plate, the intermediate valves 1, the posterior valve has 10 or 12, and some of the median teeth are bifid at the tip.
The girdle is narrow, gravelly, covered with minute scales.
The gills extend to the front end of the foot.
Length 15, breadth 10 mill.
Puget Sound (Old.) ; San Diego, California (Hemphill, in A. N. S. P. coll.).
Chiton dentiens GOULD, Proc. Bost. Soc. N. H. ii. p. 14">: <>tiu p. 0. — eft. (Onithochitoii) dent ten* <ii.i>., /. <•., LM'J : 1". S. Kxpl.
/4 WCHNOCHH
Kxped. p. :i-_M. t. -I:::1. had .— Trnchnd-r, DAM.. Proc.
U. S. Nat. Mus. 1ST*, j». :\'i:\. — '!',•< n-hydermon pseudodentiens CAR- RENTER, r.rii. &J8O. Adv. Sci. Rep. 1863, p. (J4!» : Pn.c. Acad. 8cL Phila. !*»;:>, p. 60.
This sj>ecies is closely allied to chierens L., luit dillers in the sharper granulation, tlie granules being less regularly arranged, in the tbrm <>f the- sutural plates and the color both externally and within. The girdle of dentiens differs from that of cineren* in lacking the marginal spicules characteristic of that species. The gills are long, as in rhirreus.
Gould's diagnosis and figures are extremely incorrect, the liiiht spots alonir the sutures having been mistaken by him f«>r projections. • »r "teeth," whence the name (lcntirn*. ( 'arj)enter ascertained tin- identity of dentiens with the present form by an examination of Gould's type specimen.
A series from San Ignacio Lagoon, Lower California, differs from the San Diego shells in being narrower, chiefly dark green (occa- sionally with some lighter valves), and in being more subtly granu- lated. The interior is vivid dark green. One of these is shown in fig. 65. These specimens show a short, slightly acute and beaked umbo on the central valves. In the larger northern specimens this is lost by erosion.
nil < :irs Carpenter. Unfigured.
Shell small, much elevated, green, elegantly tinted with rose and olive; valves gothic-arched, the dorsal ridge acute; lateral areas small, arcuately distinctly defined, granulose; umbones prominent; umbonal margin having a tessellated color pattern and incurved. Central areas longitudinally ribbed, ribs rounded, close, not much elevated, the interstices small, sometimes slightly decussated. End valves sculptured like the lateral areas, the tail valve having the umbo median and somewhat elevated.
Interior having the sutural plates scarcely separated, the jugal sinus very broad and shallow; insertion plates of median valvts having a single slit, terminal plates with -s-10 slits; the plates are obtuse; eaves hardly elevated.
(Jirdlemost minutely scaly, the granules very close, rounded smooth; edge with .-mail suberect hairs. ((.'/
Length 5, breadth 2A mill. ; div. 80°.
CataliiKi
i-< HNO in i (/nth!,-n.< ( lABPl WTEH v. Sci.
p, 648; Proc, Cal, &cad 8ri. ill, p. 212,
An unusual character in ihi> II, prettil'
ci.- is that the sutural hmiin.-e iitly con;
jiiLral sinus] l»y a layer liniiiLr tin- very bl
'Indt'nfn'H* [ dtntient <lld.| a false Mppeanmn- 0j
given t.. the saturee by the spot* of darker painting. (<) j/s
I-( II.\«M III I -
I. RETiPORoeus Carpenter, UnfiguretiL
Shell small, subelongate, ashen colored ; mucln-lfvatcd, u arcuate. Vulvi's sulxjuadratc, apices conct-alcd. lateral areas litil.- defined, having '•> to (>' i-oun<lc(l, obsolete riblcts, here an.l thm- with acute projecting granules. Central areas pitted all over. ; small, punctate. Terminal valves with more acute close nai riMrts. Mucro little raised, anterior. Inside with hroad -utural sinus. Insertion plates of intermediate valves with one slit on each side, terminal valves with about 12 slits. Girdle bearing dote, minute scales, which are little elongated.
Length 11, breadth 7 mill.; div. 90°.
v
Trachydermon retiporosus CPU., Brit. Asso. Rep. 1863, p. Ischnochitoii (Trachydermon} retiporosus CPR., Proc. Aead. Sei. 1'hila. 1865, p. 59.
A species like scrobiculatus ]\Iidd., the central pattern in net- work, lateral areas with 3 to 6 ribs.
Known to me only by Carpenter's description.
I. FLECTENS Carpenter. Unfigured.
Shell small, subelongate, roseate; jugum acute: lateral areas scarcely defined. Valve margins excurved, sum IT incurved, a] very prominent; valves having minute, not very c 'Miles
sparsely suhradiatinir, all over very minutely punctulate. Mucro conspicuous, anterior. Inside: sutural sinus wide, Hat: • seaivelv projecting. Terminal valves with 11. median 1 slit. Girdle very minutely granulate.
Length 8f, breadth 6 mill.: div. 110°. (Cpr.)
*•
76 IS. IIN'H'HITON.
2Y< ' u., Rep. Brit. Asso. Adv. Sci. 1863, p.
—Inchnochiton (Trachydermoii) Jiectens Cri:., 1*100. Acad. >'at. Sci. Phila. 1865, p. 60.
A variety i'rom Catalina Is. has the posterior valve with 7, inter- mediate 1 . anterior 8 slits, the mucro less anterior ; divergence 90°. (Opr.)
I. LIVIDUI Middendorff. PI. 6, figs. 22, 23, 24.
Shell elevated, teL'inentum smooth, shining, livid. Anterior valve, lateral areas and posterior valve obsoletely radiately ril>- stiiate. Central areas longitudinally costulate, the riblets sepa- rated, .-harply cut, whitish, 18-20 in number. Lateral areas depressed. (Jills median.
Length 23 mill.; divergence 120°.
Sitka.
Chiton (Stenosemus) lividus MIDD., Beitr. zu einer Malac. Ros- sica, i, p. 124, t. 13, f. 3, 4.
This species and the next have not been found by later observers.
I. SCROBICULATUS Middendorff. PI. 8, figs. 66, 67, 68.
Shell depressed, tegmentum rough, opaque, ashen or yellow- brown. Central areas regularly pitted in longitudinal series; lat- eral areas swollen, divided by a radiating groove which widens below. Girdle having narrow scales. Gills median, 16 in number.
Length 9 mill.; divergence about 130°.
California,
Chiton (Stenosemus) scrobicnlatus MIDD., Mai. Ross, i, p. 127, t. 14. i1. 4-7.
I. SOLIDIOR Carpenter, n. sp. Unfigured.
Shell small, oval, somewhat elevated, rather flesh-colored; jiifrum obtuse ; niuero elevated, in front of the middle. Valves pointed, a little rounded at the margins; lateral areas scarcely defined. Entire surface smooth, under a lens minutely roughened and very minutely punctate ; wrinkles of growth conspicuous.
hind.-: posterior yalye with 9, anterior with -s, median with 1 slit; the teeth obtuse, solid, much separated, at times somewhat roughened. Sinus wide, flat ; caves *h<>rt.
(iirdle normal I'm- TrnrJiiidr,-ni»n, the granules solid.
II \« >• Illl'
This is the only tropical Bpecief th:it I have met with, ami
very ;ii>n.)i-in:il in \\< itumpy projecting teeth, re0embliog tbote of Tnnif,-//ii. The girdle IB, however, normal, tin- extremely nil
crowded granules present ini: :i s«.me\\ hat hri.-t I \ . the mirroseopi'.
The above is taken from Carpenter's Jtfft Thety] oen is
Miis. ( 'iiiiiin-, N<». !()/>.
I. \>IM:IM«>I: Carpenter, n. sp. I 'nfn/ured.
Shell small, oval, depressed, the juirnni acute. Valves apicu- late; ashen, maculated with darker. Mucro rather raided, the posterior slope concave. Kntire surface under a l<-n- §een ' conspicuously j)iistulose ; central areas havinir ahout 7 suhparalle] lines of small but projecting granules, bending toward tl:e jiiiruin, closer on the jugal area. Lateral areas hardly elevated, ha about 3 very distant and a little larger lines of granules; anterior valve with about 18 such lines.
Interior: anterior valve with 8, central valves 1, posterior valve with 9 slits; teeth acute, long ; eaves conspicuous, short ; sinus nar- row, deep, laminated but scarcely dentate. Girdle thickly beset with most minute purple smooth scales (and occasionally corneous hairs, perhaps foreign to it).
Length 1H, breadth 7* mill. ; div. 140°.
Eaxt
.' Trochydermon asperior Cm., MS. p. 19.
The solitary specimen was found in a mixed group of species, named C. pulcherrimus Sby., and Lept. craticulatus by Dr. (iould, and coming from either Hong Kong or Hakodadi. It will be easily recognized by its* sculpture and minutely chaffy s< ; Whether it belongs to this genus or to C/urtopleura will probably be decided by the gills. (Cpr.)
I. PERORNATUS Carpenter, n. sp. Unfigured.
Shell, small, subelongate, elevated; jugmn acute; ashen or olive maculated; mucro slightly before the middle, planat.-. Central areas with subparallel strong tuberculate bars, about H) mi each side, interstices decussated; jtiLral urea granulate, sculptured in front; lateral areas strongly defined, having rounded irregularly radiating tubercles, of which there are around the margin of the posterior valve about 20, the median valves f>, anterior val\>
78 ISCHMK I II TON.
Interior: anterior and posterior valves having 7 slits, median valves 1 slit ; teeth a little acute, eaves large, pectinated by the t ul »ercles or little bubbles of the outer .surface; sinus moderate, deep, flat, smooth.
Girdle closely beset with rather flat, subpilose, minute scales.
Lemrth 1">, breadth 7-1 mill.; div. (.>">°.
Habitat >/?//
Ttchydermon perornatus CPR., MS. p. 19.
Congeneric with asperior, but easily distinguished by the very >tr"i)Lr sculpture, flattened mucro, yet sharp elevation of the .shell.
'••)
1. VIRGATUS Reeve. PI. 8, figs. 72, 73 (enlarged).
Shell oblong-ovate, minute ; valves smooth, or under a lens very finely reticulated; beautifully mottled and striped with bluish- green and yellow\ Ligament very minutely scaly, marbled. (JRve.~)
Port Lincoln, Australia.
Ch. virgatus Rv., Conch. Icon. t. 28, f. 192, ISl&.— Trachydermou virgatus Rv., CARPENTER, MS. p. 22. — Ischnochiton virgatus Rv., CPR., MS. p. 106.
( 'arpenter writes as follows of the type specimens : Two speci- mens, Mus. Cuming; minute, length 5, breadth 2 mill.; div. 85°. Shell very arched, the jugum rather obtuse but not very. Mucro elevated, the posterior slope slightly concave. It looks externally like the young of lentiginosus, being painted in the same way- olivaceous with bluish-green spots. Girdle tessellated with *mnll scales not striated; granular. The three areas are scarcely to be distinguished. Very conspicuously quasi-granulate all over. The juirular part is partially streaked with brown in one specimen, blotched with ashen in the other. The anterior valve has D, central valves 1, posterior valve 9 slits. Teeth sharp, few, long. Eaves moderate. Sinus broad, moderate, flat, not channelled.
I. YIRESCENS Reeve. PL 8, fiir<. 71, 75.
Shell ovate, valves smooth, crenulated along the posterior edge ; bright pale green ; ligament horny. (7?r.)
JIahitaf mil:/'
Chiton rh-escens REEVE, Conch. Icon. t. L'o. f. j-ji;, May. 1847.— "ft Tro'-Inj.hnnon n'rescena" Cl'R., MS. p. 21.
i! Norn I ! .
( larpenter'e aotei are as toll.,-
CiiiniiiL'-. A very remarkable ipecies, \\iili M combination of characters. IVrhap- it belong- rather win
etO, Valves rather pointed in limit, and broader behind ; oval, -omewhat elevated, jiiguni rat her .-ha rp. (in-ni, uitli one OF more valves always varie-ated with darker; line N's.-dlati..; suture-, causing it to appear toothed. Muero rather rai- • anterior third ; posterior >h>pe very concave. Valves rath' ; with conspicuous, rat her obtuse apices. Side areas scared v di-tinct. 'The whole surface is rat her glossy, hut under the niirrosropr uitli extremely line .irranulation, which runs into line lines alon- ami near the juiruni. ( Jirdle Trachydermoid, covered with extremely minute scales and occasional hairlets, but at the sutures and in a row around the margin are a series of brown dots which turn out to be semi-pores, quite regular but without hairs, only lar.Lri making a kind of knob. They are very conspicuous as pore-lumps when the shell has been soaked. The anterior valve has 11, central 1, posterior 9 slits. Teeth stumpy, like nuttallii, but not striated. Sinus shallow and rounded, with about 16 teeth, formed by the lirations of the anterior part within. Eaves short and very spongy. Length 12-1, breadth 7 mill.; divergence 113°.
I. STRAMINEUS Sowerby. PI. 8, fig. 71.
Shell ovate, smooth, pale straw-colored ; back rounded ; marginal scales sparse. (Sowb.~) Length 10, breadth 6 mill.
Island of Chiloe, under stones at low w
Chiton stramineus Sows., P. Z. S. 1832, p. 104 ; Conchol. Illustr. f. 28; Zool. Beechey's Voyage, p. 150, t. 41, f. 13.— Trachydermon straminens Sowb., CARPENTER, MS. p. 21.
Carpenter remarks : A distinct species. Five specimens in Mus. (aiming, much worn and smashed. They scarcely show the sculpt- ure ; in the best there is an attempt at granulation. Rather broad, flat, rounded jugum. Girdle gravelly; mucro median, a tritle raised ; posterior slope nearly straight. The anterior valve h:i- median 1, posterior 10 slits; teeth sharp, Isehnoid ; eaves mod, Length 1H, breadth 7 mill.; divergence about 114°, the valve- rounded.
80 [SCHNOCHITON,
I. PUSILLUS Sowerby. PI. 8, figs. 69, TO.
Shell small, obovate, whitish ; back elevated : intermediate valves narrow, very minutely punetulate : lateral areas somewhat distinct ; posterior valve larger, the apex central, inclined backward. (Sowb.)
Length 6i, breadth lM mill.
Hirnminnio, J'fi'ii, on a coral reef in 17 fins., 0 miles from shore.
C. ;>M.</////X Sows., P. Z. S. 1832, p. 57 ; Conch. Illustr. f. 31.— RKI.VE, Conch. Icon. f. 189.
( 'arpenter's notes on the two specimens in the Cumingian collec- tion are as follows: Length 5J, breadth 2-1 mill.; divergence 90°, nearly semicircular. Small, whitish-ashen, long, arched. No jugum or jugal area. Lateral areas slightly swollen ; granulated, but no other pattern. Mucro rather elevated, posterior slope very concave. Posterior valve with 11, median 1, anterior 10 .-lit.-. Teeth sharp, long and very thin; eaves conspicuous, not spongv. Sinus deep, broad, flat, not channelled. The shell might pass in sculpture for a young punctulatissimus ; in shape and size for Lep- tockiton cancellatus ; but as far as I can see the girdle scales, they are very minute and like Trachydermon, but they have mostly per- ished, and the specimens have been rather smashed and are in bad condition.
I. 1:1 I:I:K Limit'. PI. 7, figs, 50-56.
Shell oblong, elevated, solid, the back roundly subangular, lat- eral slopes somewhat convex ; surface apparently smooth except for well-marked grooves or wrinkles, indicating growth-periods, lender the microscope, however, an excessively fine reticulation is visible. The color is light buff, marbled all over with orange-red in various patterns, or entirely suffused with reddish ; usually hav- ing a red dorsal stripe bordered on each side with buff.
The anterior valve is twice as wide as long, crescentic rather than half-round. The intermediate valves are slightly beaked, their lateral areas slightly raised and having stronger concentric wrinkles than the central areas. Posterior valve having a rather elevated but obtuse median umbo.
The interior is briyht pink. The sutural plates are wide, large ; tlirjnyil *in us is deep, narrow and anf/nfur. The insertion plate of the anterior valve has 8 to 11 slits; intermediate valves normally 1 -lit: posterior Yalve 7 to 11 slits. The insertion plates are sharp and smooth.
DM ll\n< IN I The nil-die U reddish-brown. eoveivd with minute elon-at. 'I
The gills extend I'onvard to tin- middle of tin- body.
Lciiirth 20, breadth 12 mill. Al:i.-k:m BpeCUE Ii iiLi'th of an inch.
Arctic <IH<! north* rn xeas of Europe; south t<> M
\. 1'iiciiir <in<l Ilt'i-hiy* Sea from I'rih iloff Is. went to Alia, xoittlt to N/7/-</ ; l\nmrhntk<t. Low water to 80 fins.
Chiton nihrr L., S\>t. Nat. xii, j>. 1 1 <»7.— L»>\\ i:, Zool. Journ. ii. p. 101, t. 5, f. 2.— (Jon, i), Invert. Mass. p. 1 111, f. '_' 1 : edit. IJiimey p. 1M50, f. 523.— FORHKS& HANI.KY, IIi>t. Mull. (i. I;, ii, ; 59, f. 6; t. AA, f. 6.— HANLKY, Sh. ,,f Linn. p. 17. SoWEBBTj Coiu-h. Illnstr. f. 103, 104.— RKKVE, Conch. Icon. f. 175.— JEF- i IM.YS, Brit. Conch, iii, p. 224 ; v, p. 19!), t. M>, f. 4. — Ch. cinereus ( ). F.vi;u., I-'uiin. Clronl. p. 423, not of authors nor of Lin IK'. — Ch. minimum SIM-:N<JL., not of Gmel. — Ch. fan's L<>VI;N, Ind. M.dl. lit. Scand. p. 28, 1846, not of Mont., Forbes & Hanley, et al.— Ch. Ar/'/'x I'KNNANT (probably), Brit. Zool. (iv), iv, p. 72, t. :U\, f. 3.— Ch. latus LEACH, Moll. Brit. p. 231. — Chiton (Lepidopleurus^ruber JEFFKKYS, ]>iit. ^Toll. iii, p. 210. — Trachydermon ruber CAi:ri;.\i i .1:. Bull. Essex Inst. v, p. 153, 1873. — Boreouhiton ruber SARS, M«»ll. Reg. Arct. Norv., p. 116, t. 8, f. 4.— TV. ruber DALL, Proc. V - Nat. Mus. 1878, p. 320 (1879).— Chiton incarnatus REEVE, Conch. Icon. f. 194, 1848.
The shell is apparently smooth, as described by Forbes and Ilan- ley, but under a high power appears finely reticulated as observed by Jeffreys. Its color is very variable, being usually marbled red and whitish like Tonicella marmorea, but the valves may be uni- form dark red or nearly pure white. I have one specimen with the four central valves dark red and the rest white ; one valve in a specimen is often dark red, while all the others are marbled. It is most likely to be confounded with Tonicella marmorea and - varieties of T. liueata, both of which have leathery girdles, while this species can almost always be determined by its farina' girdle, dusted with alternate red and whitish patches, the latter nearly opposite the sutures. (Dall.}
I. PUNICEUS Couthouy. PL 8, figs. 76, 77.
Shell small, thin, elongated, elliptical, elevated and sharply ear- iiuited along the back, of a dull rose, or bright brick-red color, and 6
ISCIINorliri'
everywhere minutely punctured. The lateral areas are vn-y abruptly and distinctly elevated, regularly ridged by the obtusely rounded stages of growth and bearing a lew scattered granules. Central areas with the lines of increase well marked, and remark- ably barred with about six elevated, longitudinal, parallel ridges, which are generally dislocated about the middle by some of the lin.-s of increa-r. The posterior valve has a very minute, and acute, nearly central nmbo, with an abrupt depression pas-im: transversely through it; the margin is very minutely imbri- cated by prismatic scales, colored like the shell, and with yellowish band- ending it, opposite to the junctures of the valves. (G/c?.) Length 12$, breadth 7'. mill.
Orange Harbor, Terra del Fuego.
Ch. j>n,i!rrns (CouTHOUY MS.) GOULD, Proc. Bost. Soc. N. 11. ii, 1846, p. I-}-0.: Exped. Sh. p. 5; U.S. Expl. Kxped. Moll. p. .°>24, t. L'7. f. 412; Otia Conch, p. 5. — Trachydermon ruber var., CAKI-I N- TER MS. — Lepidopleurus puniceus ROCHEBR., Miss. Sci. Cap Horn, Moll. p. 140.
The gills extend forward to the middle of the foot. They are erroneously represented upon Gould's plate. Carpenter considered this a synonym of T. ruber, but it is probably distinct.
I. STKINKMI Pfeffer. PL 6, figs. 19, 20, 21.
The form of the animal is a somewhat elongated oval, bluntly rounded before and behind, the middle keel-like and elevated. ( Jirdle covered with granules which are somewhat elongated in a radial direction. Eighteen gills on each side, reaching from the middle of the foot nearly to the posterior end.
Shell rather elevated, very finely granulated. Median valves comparatively narrow, their length not much over 1 of their breadth, the posterior angles not produced backward; yo: examples having strong, acute apices, older having less projecting blunt apices. Lateral areas separated from central ana- by a dis- tinct ridge. Central areas having transverse lines of fine grains, which turn at right angles and become longitudinal on the lateral areas; there are also more or less terrace-like marks of growth- arrest. There is a system of weak radial wrinkle-stri;e, converging toward the timbo. upon the central areas, more developed in young specimens, and totally absent in the larger ones. Anterior valve half-round, concentrically finely granulated, and having coarse con-
ft HWO in i
erntrir growth-mark-. Tail valve hall'eimilar. || -eulptiired likr the head valve; it- mitral area from
than .' die length «.f die posterior slope. I'mbo aeut»- examples.
The insertion plates are nil overhung l»y the eaves, th< Ia1 jectiDg beyond them. Tin- ;uit< -rii.r valve has 17, posterior valve \'2 teeth.
The ground color of the shell baa a light reddish-white or hril- liant red tone, with more or less distinct radiating flamed <tn-ak8 of li-'hter and darker; girdle yello\visli-l>ro\vii, lighter toward the edge, with i'cw or numerous transverse tracts of lighter. /
L.-ngth 2b", breadth 14 mill.
South
steinenii PFFR., ^Foll. von Siid-Georgien, in .Juhrb. Hand). Wiss. Anstaltcn, iii, p. 103, t. 3, f. 1, 1886.
Closely allied to T. puniceus, but different in having the central and lateral areas equally granulated, and the central area entirely without longitudinal sculpture.
Section Trachyradsia Carpenter.
Trachyradsia CPR., MS. — DALL, Proc. U. S. Nat. Mus., Jan., 1878, p. \, 323. Type, C/i. fulgelrum Keeve.
Chitons like Trachydermon except that the insertion plates of the median valves have two or several slits.
The species of this group should be carefully compared with CalMntnn. and Stereochiton, with which groups they agree in the multiple slits of the central valves and the markedly spongy ea
I am not disposed to group these forms with Trathydermon but leave them here in deference to the views of Carpenter. It should be noted that Carpenter did not consider Ch. fulgetrutn the tvpe of his group, that species having been selected by Dull.
I. PULQETBUM Reeve. PL 8, figs. 80, 81, 82.
Shell ovate, a little attenuated in front, very minutely and doe decussately punctured under the lens, throughout. Terminal valves and lateral areas of the rest somewhat ohscmvly radiatrly grooved. Reddish-brown, peculiarly painted with longitudinal yel- low and black zigzag waves. Girdle horny, (five.)
H'thltat tail;/
s I ISCHNOCHITON.
Chiton fulyetrum ]Ji:i:vi:, Conch. Icon. t. xiii, f. 71, March, 1847. — / Ti'itchijrmlt'm fulgetriim CPR., MS. p. 24. — ? Chiton dental us, SPENGLER, Skrivter af Naturhistorie-Selskabet, iv, p. 88, t. 6, f. 16, Kiobonhavii, 17(.'7.
Carpenter writes as follows of the type specimen, unique in the Cuming Collection : The mucro is prominent and median, the slope In-hind it very concave. The interior is vivid rose color.
The insertion plate of the front valve has 20 slits, median valves 4 to 5, and posterior valve 18 slits. Sinus small, imperfect in each valve, but probably as shown in fig. 81. Eaves small.
Girdle thin, wide, ornamented with small, scarcely imbricating, slightly elongated, very close, deciduous scales.
Length 63, breadth 38 mill.; divergence 103°.
The scales are extremely minute deciduous, crowded into an irregular spongy mass, and when seen separately are not like a flat spine as in Callochiton, but somewhat rectangular and scarcely elongate. They have perished over most of the specimen, although that is in fine condition. It appears to have been tessellated with white over the chestnut surface but most of the specimen is now of a light horn color. The radsioid character of the valves and the brilliant rose interior makes this specimen very like castaneus but it is known outside by the obsolete riblets formed by slight depressions co-ordinate with the slits inside. Even these do not appear in the younger part of the shell. The color markings are probably vari- able. It is probably from S. Africa. (Q?r.)
I. ALEUTICUS Ball. Unfigured.
Shell small, rufous-ashen, oblong, vaulted, the jugum very acute; mucro submedian ; apices prominent ; lateral areas inconspicuous, entire surface minutely reticulated in quincuncial pattern.
Interior: anterior valve with 16, central with 2, posterior with 11 slits; teeth small, very spongy, widely separated ; eaves spongy, sinus small. < Jirdle beset with minute scales. (Dall.)
Length ('., width 3 mill.
Kyska Harbor, Kyska Id. ; Constantine and Kiriloff Harbors, Amchitka Id., and Nazan Bay, Atka, in the western Aleutians, at low- water mark, under stones on the beach.
Trachyradsia aleutica BALL, Proc. U. S. Nat. Mus. p. 1, Jan., 1878 and t. c., p. 323.
1 1\«. ••nirow. 85
This modest little species is of a dull livid purplish red, with an
aahy tinge, especially on the narrow girdle, Kxcepi r,,r th<- weii-
marked ridges of growth, it appears SIIMM.||I, hut pOWeMet ' like all Chitons) a fiiu> reticulation, only vi>iblc under a. maLMiit, lateral areas are not distinct, the back is very much rounded and the valves well hooked in the median line. The substance of the valves from within appears remarkably spongy as if rotten, or even like vesicular pumice, especially under the eaves. The ante- rior slits are marked by radiating lines of holes, though the teeth between them can hardly be made out. The posterior valve, how- ever, has not this aid to counting, and in the general spongiin is almost impossible to say how many teeth or denticles exist. It bears no marked resemblance to any other species of the region. (DalQ
I. MULTIDENTATUS Carpenter, n. sp. Unfigured.
Shell small, reddish-ashen, oblong, vaulted, the jugum very obtuse ; umbo of the last valve submedian ; apices prominent. Entire surface having the appearance of being minutely scaled in quincunx ; lateral areas scarcely distinguishable.
Interior having 20 slits in the posterior valve, 2 or three in the intermediate valves ; teeth small, solid, obtuse, deeply and broadly separated ; eaves short, spongy ; sinus small, very wide, scarcely laminate. Girdle beset with minute scales. ( Cpr.~)
Bonin Islands (Stimpson).
Trachyradsia multidentata CARPENTER, MS. p. 24.
The type is in the Smithsonian collection.
The only specimen known has lost its head valve, and most of the mantle scales; what remain of these, however, are of the Trac/u/- dermon rather than the Callochiton type. The shell was named Lepidopleurus lepidus by Dr. Gould, but has little in common with that species. There is no character to distinguish it by outside ; but within the incisors are represented by a series of roundish, stumpy, peg-shaped denticles, set rather widely apart in the short spongy gums that are characteristic of Callochiton. The three or four lobes in the side valves are rather longer.
I. LINDHOLMI Schrenck. PI. 27, figs. 35, 36, 37, 38, 39.
Shell ovate, about twice as long as wide, depressed ; olive-green, the eroded umbones rosy-white. Lateral areas and end valves
86 I-i 'UNIX IIIToN.
racliately costulate, decussated by concentric growth sulci, the rib- It -ts more or less scaly-gran ose, the interstices very delicately punc- tate. Central areas longitudinally wrinkled, the interstices deli- cately punctate. Mucro sulx-entral. Anterior valve having 16, median valves 4, posterior valve 12 slits. Sutural plates yellowisli- rose color. Girdle half as broad as the lateral slope of the valves, very delicately granulose, blackish-green maculated with white. Gills ambient, composed of 44 branchue. Length 44 mill. ; divergence 130°.
Bay of Hakodadi,
Chiton lindJiolmi SCHRENCK, Bull. 1'Akad. Imp. Sci. de St. rsb. v. p. 511 ; Melanges Biolog. iv, p. 253; Reiseu u. Forsch. im Amurlande ii, Zool. p. 288, t. 12, f. 9-16.
This large radsioid species may prove to be a Stenoradsia (see p. 61) ; but the meagre description of the girdle given by Schrenck, causes me to place it, for the present, in the decidedly heterogenous group Trachyradsia. «
Subgenus VI. ISCHNOCHITON Gray (restricted).
Ischnochiton GRAY, P. Z. S. 1847, p. 126. — SHUTTLEWORTH, Bern. Mittheil. 1853, p. 66. — Lepidopleurus (part) H. & A. ADAMS, and CARPENTER, olim., not Lepidopleurus Risso. — Ichsnochiton FISCHKK, Manuel p. 880.
Valves having sharp, non-pectinated insertion plates ; mucro median or anterior; girdle covered with imbricating scales. Within this subgenus three subdivisions may be recognized :
Section Ischnochiton s. s., in which the valves and insertion plates are thin and smooth, one side-slit in each median valve ; the scales of the girdle flat and striated.
Section Lepidozona, differing in the convex, solid girdle scale-. which are usually almost smooth.
Section Radsiella, like typical Ischnochiton except that there are two or several side-slits in each median valve.
The .-nbgenus Heterozona should properly be included here also, and Ischnoradtio is not far removed from Lepidozonn in characters.
BOTO in i'
.W///or///V (1.) (I'nmj, of I. /oiif/ininih'i.
( )l)h>iiM -.^peril's, with line, not conspicuous, sculpture, tin- central
irranulatcd in quincunx <>r in /iir/ai: patt'-rn, lateral areas radially ribbed.
The species are from A us( ralo-/elandie seas.
I. LONQICYMBA (,>uoy iV (laimard. PI. 22, figs. f>>
Shell oblong, rather highly and broadly arched, not in the least carinated. Surface to the naked eye appearing smooth on the cen- tral, radiately lirulate on the lateral areas and end valves. Color extremely variable, usually pale olive mottled with dark olive or purple-black, or having a broad light band along the back.
Lateral areas distinctly raised, sculptured with 8-12 radiating riblets, often bifurcating, the intervals densely granulated ; the rib- lets are interrupted by irregular impressed concentric growth-line-. Central areas very closely and finely granulated in quincuncial pattern ; the granulation is nearly even on the jugum, although the anteriorly divergent rows of granules are sometimes slightly more prominent ; on the slope between central and lateral areas, and <>n the extreme sides of the latter the granules are arranged to form more or less distinct longitudinal rows. The end valves are verv minutely granulated and radially lirulate. Umbo of posterior valve rather low, obtuse; posterior slope visibly concave.
Interior green or blue sometimes varied with red or corneous. Anterior valve with 9-12, central 1, posterior valve 11 slits; teeth thin, sharp and smooth ; posterior tooth of the side insertion plates short, and terminating abruptly before attaining the posterior mar- gin of the valve (figs. 61, 64) ; eaves solid.
Girdle closely covered with solid, convex but somewhat flattened imbricating scales, most of which are rather weakly striated, but among which non-striated scales are mingled (pi. 22, figs. 63, 66).
Length 33, breadth 16 mill, (often smaller).
New Zealand: Auckland to Duned in ; Pitts' Island; Auckland Is.; Campbell Id.
C. longicymba (? Dufresne, Mus. Paris; Blainville. Diet, des Sri. Nat. xxxvi, p. 542), Qn»y A- < IAIMAMD, Yoy. de PAstrol. Xool. iii, p. 390, t. 75, f. 1-18 (1834).— Hi EVE, Conch, [con. t. !'.», f. 126, t. L'4, f. 163d. — Lepidopleurus lonyiciimbtm Hni<>\. Man. N. /. Moll. p. 113(1880).
88 ISCHNOCHITON.
There is no certainty in the identification of de Blainville's lovgi- cymba but I have accepted the form recognized under that name by (v)iioy, as he was the first to figure the species. This identification coin pels us to regard the New Zealarfd shell as the type form. Figures 58, 60-66 represent New Zealand specimens furnished me by Prof. Hutton and Mr. G. W. Wright. These differ from the Australian form, which I have named Haddoni, in the much less distinct, less regular striation of the girdle scales, the broadly rounded arch of the back, and the short, abruptly terminating posterior tooth of the side insertion plates.
I. HADDONI Pilsbry, n. sp. PL 22, figs. 67-73.
Shell distinctly keeled on the back; scales of the girdle beauti- fully regular in size and arrangement, and evenly and deeply grooved (fig. 67). Sculpture and color patterns like /. longicymba.
Interior white, greenish or bluish ; anterior valve with 10, cen- tral 1, posterior valve 12 slits; teeth thin, sharp. Posterior tooth of the intermediate valves long, extending almost to the posterior-lat- eral angle of the valve, and not terminating abruptly (fig. 72).
Length 27, breadth 12 mill.
The coloring is even more variable than in the New Zealandic /. longicymba ; some specimens are clear, light greenish-buff (fig. 71) ; some are brown, speckled all over with olive-black ; some are mainly red, or black, having a wide white dorsal stripe.
Port Jackson, Australia.
Chiton longicymba So WEBBY, Conchol. Illustr. f. 67. — REEVE, Conch. Icon. t. 24, f. 163a-c. — Ischnochiton longicymba CPR., MS., and of HADDON, Challenger Rep. Polyplac. p. 17 (not Ch. Imtgifymba Quoy).
Having examined extensive suites of specimens of the longi- cymba type of Ischnochitons from New Zealand and Australia, I find myself compelled to separate specifically those from the latter locality, although in general appearance, color and sculpture they certainly resemble the true longicymba. The differences indicated above, and shown in the figures, seem to be remarkably constant, and readily recognized if one takes the trouble to look for them. It must be admitted, however, that to thoroughly examine a small ( 'hiton involves some little trouble; and therefore we must feel no surprise if the superficial collector and the often no less superficial author, continue to confound species which are really distinct. It
ft IIMM III l<
must be said, however, that the confusion of these two ip probably been due to the hick of specimens from the two localities for comparison ; else the dilli-rcnccs would hardly have escaped writers so careful and observant as Carpenter and Iladdon.
I. CRISPUS Reeve. PI. 24, figs. 98, 99 (enlarged).
Shell rather elongately ovate; terminal valve- and lateral areas of the rest finely decussately granulately crisped, central areas smooth, or under the lens very minutely reticulated. Olive-green, thickly painted with dots of a darker color. Ligament minutely grauulously coriaceous, obscurely tessellated. (Reeve.)
Australia.
C. crispus EVE., Conch. Icon. t. 19, f. 120, May, 1847.
Allied to C. longicymba, but distinguished from that by the min- ute decussated character of the sculpture of the lateral areas. (Eve.)
Carpenter seems to think this simply a pale variety of C. longi- cymba, saying that he cannot see the decussation spoken of by Reeve, unless it is from the concentric ribs of growth seen in some of the specimens.
In view of the inadequate description and figure, the species had better be dropped.
I. PALLIDUS Reeve. PI. 23, fig. 91 (enlarged}.
Shell oblong-ovate, valves smooth throughout; dead white; lig- ament horny, arenaceous, brown. (Reeve.}
Australia.
C. pallidus REEVE, Conch. Icon. t. 16, f. 92, March, 1847.— Isch. pallidus CPR., MS.
Carpenter's notes on the specimens in the British Museum are as follows, but I am not sure that these are Reeve's species : Shell almost exactly like L longicymba, gothic-arched ; whitish, ashen, or variously tinged or streaked with roseate, blue and olivaceous ; jugal area scarcely defined, jugum obtuse ; central areas wrinkle- striated, the wrinkles irregularly tending forward toward the jugum, sometimes v-shaped; lateral areas well-defined, having 12-30 gran- ulate-wrinkled stride, sometimes the wrinkles, sometimes the gran- ules predominating, sometimes having concentric growth wrinkles. Mucro median, rather elevated, the slope behind it little concave. Interior : front valve with 11, central 1, posterior valve 13 slits ; teeth
'.«) ISCHNOCHITON.
acute ; sinus very broad, flat ; eaves large, scarcely spongy. Girdle thin, irregularly imbricated with very small, very close, solid, sub- elevated, conspicuously sulcated scales. Australia. Five speci- mens, P>. M.. the tablet including two specimens of longicymba and one of Heterozona cariosa f.
In the first specimen the radiating sculpture is almost lost in the i:ranulc< in the side areas. The painting is sometimes with delicate broken lines of brown longitudinally. Sometimes one jugular patch more or less broken into streaks, side areas rarely if ever painted, but often tinged with bluish green. The specimen opened B. M. has 2 central teeth on posterior valve changed into an irreg- ular series of pectinations evidently consequent on an injury.
I. INQUINATUS Reeve. PL 18, figs. 49, 50 (enlarged).
Shell oblong-ovate ; terminal valves and lateral areas concen- trically, somewhat obscurely ribbed, finely radiately grooved; cen- tral areas longitudinally finely ridged. Ligament horny, arena- ceous. Whitish, stained with a light brown spot along the summit of each valve. (Rve.}
Tasmania.
C. inquinatus RVE., Conch. Icon. t. 23, f. 154, May, 1847. — Isch- nochiton inquinatus CPU., MS.
The shell is sometimes partially stained throughout with the faint brown color which appears on the umbonal summit. (Rve.)
Compare /. divergens Rve.
I. DIVERGENS Reeve. PI. 22, figs. 74-77.
Shell oblong, moderately elevated, varying from obsoletely to distinctly angled at the dorsal line. Lateral areas raised and rugose. Color very variable, but usually a light green tint, spotted with dark olive-brown, or cream-white, variegated writh olive, olive- brown or dull scarlet.
The raised lateral areas are sculptured with a varying number of bi- furcating or irregular riblets, the surface between them being granular. Central areas sculptured in the middle with very fine subgranose strice diverging forward /\-likefrom the dorsal ridge ; pleura or sides of the <•< ntral areas having stronger longitudinal rugce at the sides and on the diagonal slope ; a region of fine zigzag striation sometimes inter- vcninir between the side corrugation and the A'like >t nation of the jugal tract. End valves sculptured like the lateral areas. Umbo
i~< n\'M 111 1. :u
of iln- posterior valve rather acute, in front of tin- middle : slope concave.
Interior whitish or bluish, marked at tin- >inns \\itli 1>1 and posteriorly with rose ; the tail valve haviirj a conspkmooi Nark crescent in the middle. Anterior valve having l<> ll;. central 1, posterior valve 10-13 slits; teeth sharp; cave- narrow, -olid.
Girdle indistinctly tessellated with purplish on a paler Around, covered with forge, convex, closely and deeply ftriaUd 9oM -• (fig. 74). Length 28, breadth 14 mill.
Port Jackson, AurtraKa.
Chiton diver gens REEVE, Conch. Icon. t. 8, f. 44. — Ch. proteus REEVE, /. c., t. 18, f. 111. — Lepidopleitrus proteus ANCAS, I'. / 8, 1867, p. 222. — Itchnochiton divergens and Inch, proteus CPR., JA\. Isch. intricatus and Isch. intricandus CPR., MS., olim. *
This species differs from I. longicymba, haddoni and //•/// /ra*t/.>- in the very much larger convex scales of its girdle. It has the lateral areas much as in I. fruticosus, but the median portion of the cen- tral area is more distinctly patterned, and the jugum is subcar- inated. It varies greatly in coloring, and usually has some roae- pink inside.
/. divergens has been erroneously united to fruticosus by Angas and by Haddon. It should be understood that all of the detail drawings of the girdles are drawn to exactly the same scale; if this be considered, the student need not hesitate in identifying the pres- ent species.
I. FRUTICOSUS Gould. PI. 23, figs. 78, 79, 80.
Shell oblong, moderately highly arched, the back rounded, not carinated. Surface lusterless and showing distinct, irregularly radiately roughened lateral areas. Color usually grayish or light green, becoming olive-green or brown toward the sides, and more or less spotted with blackish.
The lateral areas are raised and irregularly sculptured with a varying number (3-6) of bifurcating subno<lo>r radiating riblets, the posterior one of which is transformed into a series of nodes; the other riblets often much interrupted (fig. 80), but sometimes nearly continuous; intervals between the riblets are finely granulated. The central areas are either minutely and evenly shagreened in the middle, much as in /. lonyi- cymba, except that the granules are more distinctly arranged into
92 ISCHNOCHITON.
oblique zigzag rows ; but toward the sides of the central areas, along the diagonal slope, a coarse sculpture of longitudinal wrinkles is developed. End valves sculptured like the lateral areas; umbo of posterior valve rather obtuse, the posterior slope concave.
Interior white and blue or blue-green; posterior valve having a black crescent. Anterior valve having 10, central valves 1, poste- rior valve 9 slits. Teeth sharp, thin, smooth outside, but slightly roughened inside ; posterior tooth of the side plates terminating abruptly near the posterior edge of the valve. Eaves narrow, solid.
Girdle indistinctly marbled with ashy-purple on a paler ground ; very closely covered with microscopic, deeply imbricating striated scales (fig. 79). Length 33, breadth 15 mill.
New South Wales.
Chiton ftuticosus GOULD, Proc. Bost. Soc. Nat. Hist, ii, p. 142 (July, 1846) ; U. S. Expl. Exped. p. 319, f. 428 ; Otia, p. 4, 242. — Ischnochiton fruticosus CARPENTER, MS. and of HADDON ? Chal- lenger Polyplac. p. 17. — Isch. sowerbyi n. s. ?, CPR., MS.
This species has the lateral areas more roughly and irregularly sculptured than /. longicymba or /. haddoni, and the girdle is some- what more compactly, flatly scaled than either. The external sculpture of the valves is extremely similar to /. divergens Rve.; but the latter differs totally in its very coarsely pebble-scaled girdle.
I. SCULPTUS Sowerby. PL 23, figs. 89, 90.
Shell subelongate, depressed, subattenuated in front, back rounded. Central areas smooth, striated at the sides ; lateral areas ornamented with radiating exfoliating ribs ; margin smooth. Length 20, breadth 10 mill. (Sowb.)
Habitat unknown.
C. sculptus SOWERBY, Mag. of Nat. Hist, iv, p. 292, June, 1840 ; < "nch. Illustr. No. 44, f. 66.— REEVE, Conch. Icon. no. 177, t. 26, f. 121.
A beautiful little shell, remarkable for the exfoliated sculpture of the lateral areas, on each side of which there are three radiating series of strongly relieved laminae. The central areas are nearly smooth except at the sides, where they are slightly striated. The
niaririn i- nearly sm<>oth, li.trlit brown invirularly striped with gray ; and the general color is creamy-white. (Soivb.)
EBOHHOCB] i'
I. coNTSAcrua Reeve, I'l. 23, figs. 81, g
Shell oblong, peculiarly runt ractrd ;it tin- rxhvn especially tin* anterior; terminal valves and lateral tin- rest concentrically granulated, granule^ solitary, central areas very minutely and closely ridded, ridges curved and OOD- spicuous towards the >idcs, finer towards the middle and drni»at«-d with ohli(|iie stria-: light hay, flamed in the middle with hrown ; ligament granosely coriaceous, dark hrown. (live.)
TiH*innniii • Mil-. ( 'inn
( '/ilton contractus KEEVE, Conch. Icon. 1. 1^, fi;r. 7*, March, 1847. — (1hiton. (IcciiMttH* RI:I:\ I-;, Conch. Icon. t. 18, f. 107, April, 1> 17. — Chiton rattu* IvVK., t. 22, f. 14-"), May, 1847.— /.>•'•/, n^-hitn,, castus CPR., MS., and 7. interyranosus CPR., MS. — Lr/, ;<!<,/, /, .^Hclosus H. AD. & ANGAS, P. Z.S. 1864, p. \»'2 ; /. r., 1S0T), p. 187.
This species has heen several times described, but the range of variation seems to be less than in some other allied forms, although the coloring varies considerable. The acute dorsal ridge, divergent or zigzag sculpture of the dorsal areas, the granulation of the lateral areas and serration of the sutures are characteristic. The descrip- tions of the several forms included under contractus follow below.
Carpenter's notes are as follows: shell oval, subelevated, ashv, irregularly streaked with brown-olive. Otherwise like /. c</ but the central areas are everywhere zigzagly wrinkled, the lines which in castus are conspicuously at right angles to the diagonal line are not seen in contractus. Lateral areas and end valves hav- ing close radiating wrinkles, more or less broken into granules con- centrically, sometimes scarcely at all, sometimes entirely so. Inte- rior: anterior valve having 14, central valve 1, posterior valve 13 slits; teeth acute; eaves conspicuous, hardly spongy; sinus wide, flat, smooth ; it appears broader and the sutural lamina? not so high as in castus. Girdle pale black-brown : scales as in 7. nidus. Length 37, width 17^' mill.; divergence 110°.
There are 3 specimens in the Cuming collection, from Tasmania, and two on the same tablet which are really an intermediate variety of I. castus. I cannot see the contracted sh a j H' figured hy Keeve, in either of the specimens, which are shaped just like 7. /<»i</ici/ml>a. The streaked coloring is quite exaggerated : it is very irregular, not in even lines as in Reeve's figure. The divergence is the .-ameasin 7. castus. Side by side they exactly correspond. The difference
i!\«- 111 !
in tin- >inu> is perhaps accidental, from their being older specn
"•0
'.<aahw Reeve. (PI. 23, li.irs. 83, 84.) Shell oblong-ovate,
a little attenuated posteriorly. Terminal valves and lateral areas ned, the grains rather obtuse, numerous, irregular, intei -
»ated with very close slightly wrinkled Pale \vllowi>h-<:recn, flamed along tlie suiuinit with brown.
Rpe.)
Australia Mus. Cuming, 1 specimen).
< . r,,.<tn8 Reeve. (PI. 23, figs. 87, 88.) Shell oval, subelongate, rather elevated, orange tinted with red : juirum acute: mucro rather raised, median, the slope behind it concave. Central areas cloM-ly wrinkled, the wrinkles at the ju-rum divenriiiLr laterally, sometimes interrupting one another and forming zigzags. Lateral areas and end valves with concentric nodular wrinkles, sometimes the wrinkles, -ometimes the nodules predominating; nodose at the sutures.
Interior orange-flesh tinged ; front valve with 9, central 1, poste- rior 1') slits ; teeth acute, scarcely pectinated ; sinus wide, flat, deep, >liirhtly and very minutely denticulated by the external sculpture; laigc, hardly spongy.
Girdle olivaceous, slightly tessellated, imbricated with large, wide and solid, deeply striated scales. Length 21, breadth 12 mill. : irence 103°. (Cpr.,from type specimen.)
A n^rnlin.
The ireneral characters of this species are the same as in Irstili* and rat'iosus, but it differs sufficiently in sculpture. Both of the two specimens in the Brit. Mus. are curved up so that thev cannot be measured accurately.
Another form which Carpenter described in J/N. as " 1. cimtn* n. >p.," but which he afterward decided to be synonymous with wnthut . i> white with a black «rirdle. The shell is much elevated with acute juirum ; the central areas have delicate but much raised lira, about •')<> on each >ide, and subparallel except toward the ridge where they bend outward, and upon the juirum they are elegant! v undulating. The lateral areas and end valves have rather large, separ: rly radiating, serrating the sutures. The
anteri<.r valve has 13, central 1, posterior valve 11 slit>. The irirdle U clothed with narrow, stout, deeply grooved scales. Len^tli ::n. breadth \\\ mill.; divergence 110°. It is from Su>«,t /,' MII-. ( 'umini:. No. 100).
l-« UN'" III
.</" 7'"'x"-v- Hirll I' nient.d longitudinally with n d -bni\\M, the margin with a Centric green BOne. Kml valves ami lateral area* . ally
ribbed, the ribs pii-tulo-e, interstice* minutely Lrranulated. Lateral area- stiiiirwhat elevated. Median valve- eaiinated. I)or.-al .. divaricately wrinklr-st riatr<!. (iinllc pah- l»ru\\n, eOTered with
ly imbricating scales, I.rn-th :;.'», Ix-ca.lth \in mill. (Ad.&
I
'l'hi> i> an excellent description of the exterior of this species. [. COLUBBIFEB Kccvc. 1M. L; 1 , tiirs. 51, 52.
Shell ohlonu'-ovate, somewhat elevated in the middle. Terminal valves and lateral areas peculiarly flat-drained, cent ral ana- finely reticulated with circular and obliquestlifiB, Whiti.-li l)l«>i. with Itlaek ; li-ament scaly. (Reeve.~)
Habit"! »////•/'
C. colu In- it')- RKI:\ i:, Conch. Icon. t. 28, f. 188, Jan., 184N.--/.W,- nockiton colubrtfer CPR., MS.
Carpenter writes: Three specimens, Mus. Cuming. Very like a yoiini: variety of the castu* group. Shell arched, not keeled, ele- vated ; ashy, spotted with dark here and there, tinged with orange about the umbos, which are not beaked. Central areas, and the undifierentiated jugal areas, covered with a minute granulation, runniiiLr perpendicular to the diagonal line and then brandling off into wrinkles. Lateral areas and end valves having granulations running into coarse concentric wrinkles. Posterior valve bavin- 10, central valves 1, anterior valve 9 slits; teeth extremely sharp and tine; sinus broad, deep, smooth, deeply channelled at the bi eaves long, solid. Girdle having typical Ischnoid scales, rather large, flat, broad, thin, regularly imbricated, very finely striated.
Length 16, breadth 7 mill.; divergence about 83°.
I. I-ALLIDULUS Reeve. PI. 23, figs. 96, 97.
Shell elongated; terminal valves and lateral ar utrieully
undulately wrinkled; central areas minutely rough; whitish throughout; ligament horny, arenaceous, whitish. /,'
Il'iltit'it n>ik>
C. paWidti/iw EEEVB, Conch. IOOD. t. L'O, f. 131, May. ;
IscJino'-hifon /Ktllidnliix Crii., .1/N.
96 ilN"< I II TON.
Carpi-mer gives the following aotee: Anterior valve with !'.
:al valv.s 1 , posterior valve 9 slits; teeth typically Ischnoid ;
.-inns deep, broad, channelled, flat ; eaves moderate. Jugum obtuse,
elevated; central areas very conspicuously granulated in quincunx.
ing somewhat into the Y-culpttiiv : lateral areas c»»nspicinMi>ly
raised, concentrically wrinkled, " thuinhy." Mucro central. <iir-
dle with pretty large, broad, thin, distinctly striated regularly
imbricated scales. Length 22, breadth 10} mill, ; divergence 106°.
The peculiarity of the shell is the elongation. It is probably Australian and belongs to the /. contractus group.
I. 1-1 ii \n- Reeve. PI. 24, figs. 11, 12 (enlarged).
Shell elongately ovate; terminal valves and lateral areas radi- ately ridged; ridges wrinkled, here and there grained and bifur- 1 : central areas very minutely reticulated. Burnt brown. Ligament granosely coriaceous. (Reeve.)
('. Httulatus REEVE, Conch. Icon. t. 17, f. 102, March, 1847.— !.«•},, lor/titon ustulatus CPR., MS. — Lepidopleurus untHftitn* A N< ; AS, P. /. - 1*<>7, p. 222.
Carpenter briefly notes that the scales of the type specimens an rather gravelly and irregular, very small, but apparently a little >triated. The drawings of scales and valves given on my plate were prepared for Carpenter, presumably from specimens in th»- collection of Mi-. Win. A. Ilaines, of New York City.
I. < -A KI NT i. ATUS Reeve. PI. 23, figs. 94, 95.
The finely keeled Chiton. Shell oblong-ovate, terminal valves and lateral areas of the rest concentrically and radiately somewhat obscurely ridged and sculptured with obtuse granules arranged in wrinkles, central areas also granulated, smooth in the middle, peculiarly keeled at the summit; ruddy rose; ligament finely squamately coriaceous. (Rve.)
T«.<i
C/i. r.i,'hu</tifn* RKKVK, Conch. Icon, t, 23, f. 158, May, 1847.— Tschnochiton cnriiinlntun OK., MS.
Carpenter's notes on the single type specimen in the IJritish MiiHMim are as follows: Along, narrow, rather ;,o///V-///vm/ >hell, the shape of longicymba. Girdle with very small, distincilv but ti n. ly striated scales. Mucro at the anterior fourth. .Ingmn rather
ilN'M III I
shaip, curiously marked by a long, narrow white line \\i,i, h ,
he accidental. ( 'flit I II I areas li:i\ 1!
granulation! : falling invjuhirly into coi rin:at inn
-rain-. Lateral aie;i- moderate! v rai- -I. \siili
wrinkling pa.-.-ini: OVer about four very lilunt ob-ohte rib- : end
Valves obsoletely radiated. Inieiior: posterior v:il\. 11,
mitral \al\vs 1, anterior valve 1 0 -lit- ; teeth sharp, i.in ;
sinus broad hut shallow, very -traiirln, -mo^th, not channelled ;
eavee moderate, rather close to the teeth. Len-ih LI}, breadl
mill. : divergence Id.". .
I. CUIMIHVM - I'-. A. Smith. PI. L'l. li-. U lenlai
Shell oval, llattish, of a dirty dark irravish color, havini: a • spictious black hroadish line from end to end do\vn the middle of the hack, with a pale one on each side of it, and with the mantle patched alternately li^lit and dark, irregularly granulated through- out. Valvi-s arched, not carinate at the vertex, with verv indi- lateral areas, exhihiting strong concentric lines of growth, e-pecially conspicuous at the sides and anterior maririiis. Front plat*- well curved anteriorly, the posterior margin beini: hroadly sinnat' d. Second plate longer than the other intermediate valve-, sli-htly incurved on each side, the central outcurved point in front, rather peaked in the middle of the hinder edge. The third, fourth, fifth, sixth and seventh valves are very short in comparison with their width in proportion as 1 is to 3. The jngal sinus is large and arcu- ate. Last valve of a narrow acutely elliptic form, with the n prohably near the center. Interior of the plates greenish-hlue, stained dark hrown in the middle. Lt'inina- of in>ertioii in tin- front plate with about ten notches at unequal distance-, leaving diflerent sized teeth between them, which an- ,-tiiated on both .-ides, but more strongly externally, their edges being sharp, but not smooth. The central plates have a single minute notch OH each side, the insertion lamina being Comparatively Miiooth on the upper surface and marked \\ith a small brown spot on each .-id the edge of the valve. Tail plate much thickened \\itliin aloii. posterior edge, which is roughened by fine crOSB stria-, th- no prominent teeth, and of course no notches. .Mantle mar-in cov- ered with small snbimbricating oval grannies. Length without margin l(i mill.; width of fourth plate '.».
98
The granules of the surface have an irregular concentric <1 tiiin, fnllo\\iniLp t<> .-Mine extent the lints of growth. (Smith.)
r<>rt Curtis
Chit»it i l.<rhnnrl,itiin - curtwctnut SMITH. Kep. on /ool. Coll. II. M.S. 'Alert; P. 78, t. 6, f. I). U
This i- certainly not a typical /^-hmn'hifou. It i- difficult, with- out an examination of a Specimen, to refer it to its proper gcnu-.
I. BXiouuB Sowerby. IM. i>3, figs. 85, 86.
Shell oblong, small, rufescent, narrow. Intermediate valves hav- ing a very wide trigonal dorsal cariua, the margins grooved : lateral *s distinctly defined. Length 4*1, breadth !•:; mill. (Soivb.) This is the smalleM species Mr. So\\erl>y has seen; the dorsal ke.-| ot' the intermediate valves is very broad, and distinguished l>y OV6 <>n each side. (Sowb.)
•d Hood's ItlamI, 7V//mW». <>n Pearl ()y-
riu'fnn exigvuiSoWB., P. Z.S. 18,32. p. 104; Conchol. Illustr. f. 36. — REEVE, Conch. Icon. t. 28, f. 186. — Ischnochiton exigwu Ci-i:..
Carpenter writes: Interior: end valves having 14-16 slits, cen- tral valves 1 slit: .-inus wide, curved; girdle irregularly clothed with large, slightly striatulate scales. Habitat, Centm/ I'-n-ifi*- (Pease). Mr. Pease's solitary specimen seems conspecific with Mr. Ciiminir's hitherto unique specimen from Lord Hood's Island. It is in better condition than the type, but extremely minute and evi- dently very young.
2. Group of I. textili*.
itral a i-eas granulated, becoming striolate at the sides: lateral areas radially wrinkled. South African species.
\ 1 1 us Gray. Unfiyuretl.
Shell itbhnnj, e/oHiftite, white, pellucid when youn<r, f/reen ^clth a
»//////• i-rnfrnt /'"ml ; convex above: end valves and lateral area- of
the middle valves finely radiately striated and concentrically
wrinkled; central area closely an<! minutely jiuncfufcd, find /»'liin<I
longitudinally *t/-i<it«l ; maririn [girdle] white, minutely scaly.
jth one inch and a half. (Gray.)
('"peof Good I/nj.c (Capt. Carmichael, Mus. l>rit.).
Cli> \U (-i: \v. Sjiieileiria /oolo^ica, pt. 1, p. ">, pi. (I, f. 20
Muly 1, 1828).— KRAUSS, Die Sndafiic. Moll., p. 38.— (?) I'h.solca
UN... Ill I' !•!»
.. ( 'ouch. llliMr. !'. HI n»i d.-crihed, RE •////.>•). — Not ( '/i. //•./•//// '.'I .
The ahove dc-ciiplio|| is from '
taut panagee hem- italicized h\- on
worthless. Keevc's liiruiv and description do n..t pi -rtain to t hi-
species, hut to I. (Radsiella) xebra Kran- , true /. ••
iii all respects a typical Ttehnochiton, I refer the no d C.
mtlt-,1 of Suwerhy to t,.rtili.« becaOM il i- -aid to IK- that tpeckl l>y S,. \vt-rhy hiinsclt'; l»ut the figure i> VTV poor, The detaUl h
u'ivcn will enable studenta to identify (H .ith eomj
alive ease and certainty, without a figure; for it wemi to he closely allied to the /. oni*<'n.t only ainoiiLr South African < 'Into details of sculpture of the central areas and the coloring «-em to he especially characteristic. Krauss de.-crihe- specimen.- collected hv him, and which he at one time considered a new species which he intended naming C. li«l>r!</i. His description is as toll
Shell ovate-elonpite, semipellucid, snhcarinated : white in the middle, the sides ashen-green, often spotted with hrown ; int white. Front valve lunate, tail valve rather depreased, >uhmucro- nate in the middle; intermediate valves having the central areas finely punctate on the ridge, longitudinally striolate at the sides; lateral areas and end valves radiately rugulose-striated. (iiidle a-hi'ii, suhniaculated, scaly, the scales small and ohlonir, > . finely multicn rln ,<ifed. Length 22, breadth 11 mill. Tahle Uay.
The anterior valve and the posterior part of the posterior valve are radially wrinkle-striated and have 1 '_' >lits in the insertion plates, which are smooth and shorter than the eaves. The median valves are rather narrow (8'6 x 3 mill.) and have distinct lateral areas with 5 to 6 strong wrinkle-like and interrupted stria-. The cen- tral areas are seen under a lens to be covered with fine raised points, which toward the margins become more and more di-tinct, and near the lateral margins as well as in front of the hit oral areas they unite into distinct longitudinal rows. The sutural plates are rounded; insertion plates short , smooth, and having a single slit. The girdle is covered with extremely small, thin longitudinal » not discernahle to the naked eye, and prettily marki d with 8-9 stria\ The color is whitish in the middle of the shell. Lrrayish- green on the sides, and dotted and llecked throughout with brown.
Krauss also describes the following :
100 1-' IIN«»< III 1
Var. jiuni'tn/'ttu. Shell carinated. ashen-wbitisb, unicolored or
> d and dotted with brown ; very finely punctate. Lateral areas and end valves radially striated. Length *2'2, breadth 10 mill. Tin- valves are keeled and covered with regularly arranged
..:«-d points only to he seen under a lens.
A- an illustration of tins variety Kranss refers to Sowerby's Gout-hoi. Illn.-tr. fig. ">"), but in my opinion this i- not correct.
I. OKI8CU8 Krauss. PI. 20, figs. 12, 3, 14, 1 ").
Shell small, ovate-oblong, tbin, semipellncid, subcarinatod ; white, rarely with a reddi-h dor.-al baml, or yellowish with green dots.
Intermediate valves having the central areas very finely punctu- late in tbe middle and longitudinally striolate at the sides; lateral areas and end valves finely undulately striolate. (iirdle yellowish, mandated with Lrreen, scaly, the scales very minute, oblong, smooth. (Kraws.} Length 10, width 5'6 mill.
Natal, on the shore.
Chiton oni'tcus KR., Die Siidafric. Moll. p. 39, t. 3, f. 4.—Tschno- chiton oniscus CPR., MS.
This species, whilst it has a superficial resemblance to /. text His <iray, is readily distinguished under the lens by the smaller and smooth scales and by the smaller number of slits. The valves as well as the girdle appear smooth to the naked eye, but the lateral areas are visible. Under the lens the central areas are very tinelv punctate on the dorsum, and on the pleura they are longitudinally striated ; these stria3 continue upon the lateral areas becoming wavy there. Tin- end valves have feeble wavy stria? toward the margins, and have 10 slits in their insertion plates. The intenne- diat«- valve- are strongly convex, ~> mill, wide, 4 lon^r, rounded at both .-ides, and having a single slit in each insertion plate. One specimen is white with greenish-brown girdle ; another is whitish with a rod-brown hand along the back ; a third specimen is dirty yellow with green dots, the girdle also green dotted. (Kru<
( arpenter gives this note on specimens received by him from Stimp-nii : Terminal valves having 10- PJ, central 1 slit: teeth acute ; eaves short, spongy ; sinus broad, Hat. In one of the .-pen- men- examined the hind valve has the central teeth very small and close, while the side teeth are long and distant.
In] I. YI:I:I;I I:M }•'.. A. Smith. I'l. 1 1.
Shell small, depn».-d. >li<jhlly carinated in tlic middle; -ray maculated with dull L'reeii. Lad -ral ;uid
anterior valve sube<|iially reticulated all OT< 'he poste-
rior valve subceiitral, moderately acute; -irdl.- «-,, \n.-d with
minute BCal66, POSy-gray maculated with dull green. Len-th 15, breadth 8 n. ill.
C/i/fo;/ ( :l.«'hnorl,;to>i) tjcrlntrij'i SMITH, 1'. /. ^. 1891, ]». U<», j,|.
n:;, i: (;.
Only a single specimen <>(' this species wa- found l»y Major 5 Itury. The sculpture re<-alls that of a thinihle. It i» a trifle coar-er on the lateral, especially aloni: their posterior margins, than on the central areas. The dirty green spotting is also more notic, on the hinder edges of the valves than elsewhere. (Sin
I. M vrcii.i.ivRAYi Carpenter, n. sp. Unfigured.
Shell elongated, small, elevated, the purum sliirlitly acute, valve- heaked ; ashen-hrown or pale ashen, often elegantly painted with lines or angular flames. Entire surface minutely gran n lose ; lateral areas scarcely defined, having radiating wrinkles, not very distinct. Mucro median, little elevated. Interior: posterior valve having 12-13, anterior valve 12-11, median valves 1 slit. Teeth subacute ; eaves very conspicuous ; sinus wide, flat, smooth. Girdle cl< covered with delicate, subelongated, strongly lirate scales.
Length 14, breadth 7 mill.; divergence 110°.
Tristan d'Acunha (Macgillivray, Mus. Cuming, No. 74, 92) ; St. Paul's (Mus. Ginning, No. 7).
The specimens from the last locality have the teeth acute.
This shell has the general aspect of Trachydennoti a/t>u.-< hut is longer, not so sharp at the ridge, more highly sculptured, and tin- scales strongly lirate. The pattern varies greatly in the specii It is nearly related to /. OHI'M-H*, and a larger series of individuals may prove them identical (Cpr., MS.)
I. RETICULATUS Reeve. PI. 20, figs. HI, 17.
Shell oblong-ovate ; terminal valves and lateral areas of radiately ridged ; central areas rudely and closely reticul;, dull brown ; ligament horny, rouirh. i Heeve.)
Wei I
102 l-< IIN(>( HI I •
Chiton tcj'titi.-* WMr. Sown.. Condi. Illustr. i'. 01, according to Reeve. — Chiton retimlntu* Rv., Conch. Icon. j,l. ]."">, fig. 83 (1847). — hchnochiton reticulahis CIM:.. .!/>'.
Reeve states that this is the textilis of Sowerhy hut not of Gray, and lie i- probably right, although his own identification of text ilia ( iray is erroneous. Carpenter gives these notes upon Reeve's ty pi- specimen : One specimen, which is over-colored and over-drawn in Reeve's illustration. It looks to me like a line textitin, as Sowerby seems to have taken that species, but I have no /<•./•/ ///* by me for comparison. It is very light brown, with little black irregular dots which appear to be adventitious. Girdle typically Isclmoid, with moderate-sized striated imbricating scales. Fine radiating ribs on the lateral anas, very numerous on the terminal valves; honey- combed in the middle ; jugum very much rounded. Anterior valve with 14, central valve 1, posterior valve 12 slits; teeth sharp; sinus very broad and flat, not toothed. Length 303, breadth 16 mill. (Cpr.)
Compare textili* Gray, from which this differs in coloration and apparently in sculpture.
3. Group of I. ri**oL
Small species having longitudinal riblets upon the central areas, and continuing backward over the lateral areas. These are closely allied to the group of /. striolatH*.
Distribution : Mediterranean, African and West Indian.
I. KISSOI Payraudeau. PI. 20, figs. 1-7.
Sln-11 oblong, elevated, the back regularly arched or snbcarinated, side slopes convex. Surface longitudinally 1 irate on the intermedi- ate, concentrically on the end valves. Color pale brown-olive, the lateral areas and end valves more or less maculated with snow-white and In-own.
The lateral areas are moderately raised and sculptured with coar.-e. Hat, uneven-edged longitudinal riblets, which are separated by narrow punctate intervals and are frequently irregular; under a higher power of the microscope the surface appears to be min- utely punctate, the dots whitish. The central area> have cl«»e. line riblets in the same direction, somewhat finer on the dorsal ridge, and giving way to a minute punctation in the region of the beak of
HNOCHIT' [00
each valve. The umbo of the posterior val^ ml ami :
eratrly elevate. I.
Interior white ; >utm-al plates raiftll, -»-p:iratrd id*-,
flat siim-. Anirrii-r valve lia\in-_r !•"•. po-in i..r valve Ml tral valves 1 slit ; teeth .-harp; eftVei narrow, .-hurl, -olid.
( ;irdle covered with rl. -mall, Btl ialulale, in
scales. Length !•"), breadth * mill.
.!/- dit( i i-'ini'tin and A<> r>
chiton rtwot I'AVI:.. Moll. Cone, p. 87, t.
PiMi.irn, Knum. Moll. Sicil. i. p. 107. — C\ri i IIM, .I«.iiru. <!«• Conchyl. (2) iii, p. '^2'2 (1«S")J)).— Issr.i., Intonio ai Chiton dd mare di (Jonova, in P>iill<'ttim» MalacologlCO Italiano, iii. p. ."», t. 1, t (1870).— MOFTBBOSATO, Journ. de Conchyl. 1*7\ p. 117.— I. I)\i T/.. .\: DOLLF., Moll. Mar. Rouss. p. 495, L 81, t'. 10, 11, 12; t. tt'2. t'. 2. — r/t. mriH't/hinii. CAPKLLINI, Joimi. dc Conchyl. (*2) iii, p. 325, t. 12, f. 1. — Ck. inediterraneu* "Gray MS.," I; >nch,
Icon. t. 23, f. ir>7 (1847).
This species is well characterized by its flat close concentric rib- lets and the sparsely scattered snowy spots on the end valves and lateral areas. The sculpture of the lateral areas is irregular and variable, the riblets being ragged-edged and occasionally sul> lete, leaving the raised areas almost smooth. The C. />o/ii Phil, is readily distinguished from this species by its difft-ivntly formal posterior insertion teeth ; in ri**oi the posterior teeth are normally Ischnoid.
The Ch. mediterraneux of Reeve is simply a synonym of the typi- cal form of this species. The form which Reeve calls risso Icon. t. 19, fig. 122) is a synonym of the variety meneghinO.
V&r.meneghinii Capellini (pi. 20, figs. 8-10). Sculpture stronger, the end valves and lateral areas exhibiting distinct radiating stria-.
Var. frayill* Monts. (Enum. e Sinon.). Smaller in si/t\ the sculpture obsolete, without trace of radiating stria-.
I. PERTUSUS Reeve. PL 20, figs. 18, 1 !>.
Shell oblong-ovate, valves elevated in the middle, very cl grooved throughout, ridges of the central areas thin, nm\vr_ towards the umhones, interstitial grooves pricked, posterior edge of the valve serrated ; dark red, sprinkled with a tew minute white dots; ligament horny, very sparingly b«'.M-t \\ith short hri.-tli->.
lui BCHNOCHITi
Th»- pricked inter-tic, n tin- clo>e-set ridircs which consti-
one of tlu* distinguishing features of this species are scarcely
:iihle without tlio lens. (Rve.)
Simon's /*'<///, Cape of Goo<l II
C.i i: . i < >nch. Icon. pi. xvi, £ 88 L847).— -IMfioc&t-
1 !•!:.. .l/\
rpenter*s notes from two specimena in tin- Cumin-.: collection
areas follow*: The liur'iiv in Keeve doe- nut rcprc-cnt it well. It i- one of the /•/»'»/ irnmp. Shell much arched, elevated, lint the juiruni rather blunt, t'mho of posterior valve raised, situated at the anterior third ; the -lopr hehind it very ,-liirhtly concave, nearlv
jht. <JinlU» with Isclinoiil scales, but small, long, somewhat
iinlirieatinir and >triated. Color oliv:uvou>, varie«rated. JiiLral area imt deiined from the central areas, which are sculptured with v« TV numerous and line rather blunt liruhe with extremely small inter-ii<'-: <>r the >url'ace ini^lit he described a< finely «rniov« d. ThcM- .-mail rihlets are longitudinal, very slightly «rrai)o.-e, and at the diagonal liordrr of the lateral areas become rupilose, passing on to join with the riblets of the latter, The lateral areas have about '•' to 12 very fine radiating rihlets which are m::de i:ran«»e by the longitudinal riblets from the central areas cro»ini_r them. The end valves have very close and regular radiating rows of Drains, the -culpture bt-inir very like that of C'ltrini/ntii*, but in that species the i-oiic.-ntric wrinkles predominate. The head valve- has TJ slits, median 1, posterior valve !) slits. Teeth quite sliarp, with lonur |>ro- jectiipj; eaves, which are not spongy. Sinus broad, rather deep, flat, -m. .,,th. but deeply channelled on each side at the inner has.snfthe sutural plate-. Terminal valves stained with brownish-purple inside. :li :;•_'. breadth K'.; mill.; divergence 113°.
I. i \:\ HII:«>N«>ITS C. ]\. Adams. Unfi</n,; <l.
Shell small, snbeloiiirate. [ convex, not carinated]: yellow-wliite, [the back] irregularly maculated with red; lateral areas ribbed, the rib- n. .diilons: d«»r-al area< [silicate-] striated; «;irdle scaly [ vel- !•• \\i-h-\vhite. maculated with ashen]. Length 1 .'J ,;, width 7', mill.
\danisi: >V. Thnnin.* ninl r<,,-t<, Him (\\\\\\\\\*>v <.
Cli IhronakuC. P.. Ai>., Proo, BostSoe, N. II. lv
— 1 . I ;,'»lrliifnn) t'1-iltlii-iniufii* SnrTTI.W., I>eril. M i 1 1 lie! I . !
The pa--a^cs in brack. -i- uf i w<»rt h's Interpolal i'
I. i \ 1 1 1:1 1 ii - Shuttleworth, I 'iiiiy
Shell clliptical-ohluiij, (-,,nvc\ ; l.i
with whitish; end valve- .-iihcuiicent rically HIM -ah- and pun- Mt diiin valve- imt c:i rinated ; c, ntral ft]
impn-sed, becoming transversely cottulftt nibmloate at 1
lateral areas suhelevated, radiately snh-ulcafe and minutely punc-
tate-foveolate, Girdle unioolored nil. dm^-iv bc-et with minute
flattnird icalet, Lrnirtli I L\ l.ivadth H mill. >SI,,,tt/w.)
•SV. '/ ln,,» ' . II .
(Ifchnockiton) A//r/-/////x Snr'rri,\\., hia-n. n. Mull, in i. Mittheil. 1853, p. 75, I havr nut idcntiiicd this sju-cii s, of which Shnttlcwurth wr. I have two specimens. The color i< an int< -nse l.rick red, l.oth iinide and out. It is allied to ( '. cnjtlirnnntti* ( '. H. Ad., lint ditN-r^
abundantly in toe sculpture and color, and in the 1< .-> elun-at. d shell.
4. (,'rnnji of I.
Small species, apparently smooth, hut under a len.- shuwini: a sculpture of longitudinal rildets or lines of grannies on the central areas, interrupted on the lateral areas, which arc niuirlu-niMl hy peculiar irregular impressions (pi. 1*, tig-. 54,55 . It i- difficult to describe the sculpture of the lateral areas of these >[>••« it-- : it i- what ( 'arpenter called " thuinby " or " pollicaroid."
Diatribution : Antillean and I'anarnic
Sped i'" ii'ifh >•//•/'//'
I. STRIOLATUS Gray. PI. 20, figs. 20-24.
Shell ohloiig, moderately arcln-d, the hack sometime- distinctly, sometimes scarcely visibly keeled; side slope- convex. SB showing no sculpture to the naked eye, hut having the lateral : moderately di-tinct. Color e\ce--ively variable but generally
either olive-green or olive-slate colored with white ur creamy t!- or cream-culore<l, minutely mottled with light bn»wn. The i riur ed^e of each valve i- dolled with light and dark, form sutural articulation.
106 IN. .rim
Lateral areas slightly raised, sculptured Longitudinally with //«/•- row zi'/:<i<i i/i-woe*, the eleva\'«>n* l»iu-,'t n tin m (Int. «//</ der «
to be »io.</ munife/if pHxfii/nt'. the ptiMules whitish. nil areas coven d with <m CXCCSSlVely ////'. ('/<>••<>' (jiiium
/licit be<'tnnr.« *tiyht/y <•«*//•>•/ /• t»u;i,-<l ' where the
•_li-it<lmtl/y brnmif nt> <•</«/ info Ion f/ifniliim/ i-inr." 'jicitKi (i ///•«//'• <ij,i to the pi' in- 1, especially to the part Iving at and
iiiuii.Mliat.lv in front of the diagonal line. Knd valves having con- centric /iir/aL and a minute granulation, like the lateral
areas; |>o>terior valve having a moderately elevated, central unilio,
rior >loj.c concave. Interior liirht «rray-l)lue or white : ani> valve with !>, central valve 1, po>teri«,r valve !» slits. Teeth .-mooth, >harp. Maves narrow, solid; sutural plates wliiti.-h, rather wide and low: sinus Hat, angular.
Girdle whitish clouded with blue, or blue marbled with white, generally having some small yellow or orange flecks. It is densely covered with imbricating, deeply striated scales. (PI. 20, fig. 24.) Length 14 to 15, breadth 8 mill.
St. Thom<t-
GRAY, Specil. Zool. p. « (1828).— KI:I:\ i , Conch. Icon. t. 22, f. 144.
The coloring of this species is extremely variable, and the sculpt- ure, while it is unmistakable when seen under a sufficiently hi^h I lower, still varies considerably. The side areas and end valves are generally sculptured with the concentric zigzag grooves described above (fig. 23) ; but occasionally these become &o irregular and broken that the surface appears coarsely granulous or scaly. The West COUM species di*par 8owb. and utl<nn*ii Cpr.. afl well as the /V,>-M*X of Sowerby, all belong to the #fi'i<t/(itnx ^rouj), and are closely allied in sculpture. There are also a number of described West Indian Ischiiochitons which seem to be either mere >ynonyms of /. >//W<//"*, or closely allied forms, the « xact status of which it is (piite impossible to fix with certainty until the origi- nal types can be examined by a competent person, thoroughly ar«|ii:iinted with the Mibject. The original descriptions of these forms here follow.
C. Bquamuloetu C, 1»- Adams, shell olivaceous, ornamented with a pale green dorsal line; lateral areas covered with prostrate
UN." 111 1 |<>,
unequal ICaleS; n-ntral area! mark -in- 1., ill ill the middi' striale ; girdle I"" illernalt i
Length 17 breadth Hi mill. < Ad.)
Chiton .tiiininiHlnxti* .\|... ProC, I' Ili-t. ii. :
— C. : guamu/Mu* SHUTTLW, I1., i n. Mittln-i: Thia ia unquestionably the same form I havr d< ~nil>< .1 ab
The name AtfOmtt&MU* will therefore h»-e..mr ;i
C. lutulutti* Shutllw. Shell small, elliptical-ovate. narrower in t'ront ; dull olivaceous spotted with wliih-; tcrniiiiiil
valves impressed-punctate, toward the margina irregularly concen- trically Buboostulate ; jugum not keeled; di»i>:il ana- tim-lv and regularly imprCSSed-punctate, and touard the niai'-iii- th'Miondv and irregularly transversely j)lieatulate. (Jirdle olivai-nm- and spotted with white, the >e;,les small, flattened, iml)rieat<-d. L.'ii-jth 1-J, width ^ mill. (Mnttfw.')
I ' ' • I
Chiton ( I«rh>i<>('hit<»i) lutu/<ttn« SuriTl.w., /. r. p. 7«'». 1
This was described from a single specimen, and slid to ditfl-r from C. xfy////m///Wx/x in being narrower with more regular sculpture. I have no hesitation in considering it an absolute synonym of /. striolatus.
C. carrifaorum (Cpr.) Smith. (PI. L'U, f]gi. 26, 26 , >hell lengthened-oval, scarcely carinated, variedly painted, grayish-olive, white, reddish and olivaceous, or purple, sometimes hlarki.-h with white markings; end valves concentrically and roughly gn.' striate or scaly, central areas ornamented with delicate, curved. flexuous, granose lira1; lateral areas roughly <rrano-c ..r -<-aly. Posterior valve slightly concave behind the central aj»e\. <iiidle minutely scaly, covered with elongate oval -cales pa'e i tessellated with diluted black. Length '27, diam. !• mill.
St. TttoHi'i*; J
The above appears to be a manuscript name attached to S] mens in Cuming's collection which are identical with tew shelU from Fernando Nonmha. The color is very variable, >. ' mens, when viewed from a distance of twelve indie-. app«-aring olive-grav, speckled with white; others are of a pinki-h en-am color speckled with red or blotched along the; >id« - in front "f tbe
108 ISCIIN'M mi •
lateral areas with black, as in some of the specimens from F» -rnando Noronha. Tin- granules or scales of the lateral area and on tin- front and posterior valves are peculiarly Hat and arc somewhat tran>versely arranged on the former and concentrically on the lat- ter. The central areas are finely punctured along the center, and become more and more coarsely grnnoM-ly lirate as the sides are approached. One example is almost entirely reddi.-h purple, and others are blackish with a broad pallid stripe down the middle from end to end. (Smith.)
('/litnn (Itcknochiton) caribbatorum (Yi:., J/.s'.. SMITH, .loiirn. Linn. 8oc, I. 'iid., \x, p. 4(.>o', t. .'{(), f. ~>, 5a.
The dimeiiHons given hy Srnitli may possibly he a mistake, for the iark on his plate is only I-')' mill. long. In other respects the description and figures indicate no tangible points of difference from the /. .<t,'it,I<itu«.
< arpenter's original description of carribceorum is before me, and it is an excellent word picture of some of the St. Thomas >pec- imens of *t, -io/iit u*. It is worthy of note that Carpenter recogni/ed the specific identity of >7/-/V>A////x, ciiriblm-nrinn, j<tnmi<-i-i,si.« and ."ijii'inin/oxi*, in one of his later notes.
/.(/ oaribbasorum var.) jamaicensis Cpr. Smaller than <-n,-ibb(K-
-. the lateral areas scarcely defined. Length 7-j, hreadth 4, alt. 1 i mill. Habitat, Jamaica.
/. (t jammcentis) viri<Hor Cpr. Larger than /. jnm
i. variously maenlated with olive; interior: posterior valve having x, anterior !», central valves 1 slit. Length 11 !, hrea«lth 7 mill.: di\n j» IK »• 100°. There is no character but size and color by which this solitary specimen can be distinguished from the Jamaican -hells. ( ( )//•.)
The sp»cific identity of the<e two .1/X forms with /. N/,vV//>//>- was COncede.l I iy ( 'urpenter.
Lfuniculahu Carpenter. Shell small, strongly oval, suhelevated, the jii'jnm little acute: pale ashen, ochraceous or olivaceous varie- gated: mucro central, moderately prominent. Kntire surface wrinkh-d and minutely pitted: wrinkles >nhregul:»r. nearly j.aral- lel with the d..r-al rid_re on the central areas, ahout 1 x on each >ide, Obsolete toward the jugum j the moderately distinctly defined lat- M and the end valves undulated and having sul)ohsolete radiating liruhe. Interior: posterior valve with 7-i>, anterior valve
BNO4 HOT
7 in. central valve- I -lit. 'I
wide, ll:ii. ( iirdle lurid-lied \\ ith \ .
tened M-ales. Length 10, width .') mill.; di\<
(.'iKi'l.l/nllf,,- . Mil '
( >ne specimen Is of a pale yellowish tint flight]} -I \\iih :i
brighter color; another i- in .iv a-hy and \vil li t lie \ : pale olive. h has stronger .-culpture than /. <•//, •//,/,*/•»,,•///;/. ruguhe rising tij) like close rungs in a rope-ladder, and denta' the sutures. ( ( '/»-.')
The above deseri|>t ion, from Carpenter1! .!/>. defioei a fonn which will probably prove to he a variety of T.cwil \\hieh species Carpenter, at a later date, united it.
I. PBUINOSU8 Could. IM. LM, fitrs. 27, 28.
Shell small, elongated, nearly elliptical, convexly elevated, earinate. or rather somewhat doubly carimite alon^ tlie hack : §or« t'aee generally covered with microscopic |)iinetnres, ai-raiiLrfd in lo/.'.-ni:e. Lateral areas very slightly rair-cd, and longitudinally imbricate-sulcate ; central areas with faint line wth and
punctures in quincunx ; anterior valve concentrically .-triate, not punctate; posterior valve slightly nmbonate, and rn»-> ed l»y a Iran-verse ridge, behind which it is concentrically Mriate. 1 frosted or mottled with dark brown, ash, purple, green. Are. Mar- gin minutely granulated, so as to look hoary. (Old.)
"Some specimens are of a uniform pale green. Margin chmdrd with dark green; some had two or three distinct, white blotch. the sixth valve, the rest of the shell being olive-green, with a line of faint green along middle of back ; another had the ground-colour a clear olive, three dark brown spots bordered with white <>n each side of posterior margin of valves, a row of similar spot- surround- ing the terminal valves just above insertion, and the whole sin sparsely and irregularly spotted in the same way nt a
delicately mottled a-pect. A fourth variety wa> of a uniform dark rosr-oilor. and the margin clouded with dark red band<. Inter- nally it was dark red or rosy along the middle, and dull yellow toward- the sides. All the other varie. i greenish
hue internally." (Cnnfli. i,, <;!<!. >
Length 17 '. breadth * ; mill.
Off /•''"•' •s'""/" OrVft H'" •/"""''•", "" stone- in 'J or :i t'ms.
1 111 tSCHNCH IIITON.
-"v(;M,. I',, Soc, N. II. ii. p. 144, July ls4(J:
otia Conch, p. 5, 242; I . S, ExpL Exped. p. 316, t 419.—
iiir.iMM, P..lyplax. Cap Horn, p. 141. — hchnochiton pruino- CPB, .V>. p. 77. 103.
Carpenter seems to consider this the same as mr'iblxtnm,,, and ' iht* ; hut the specimen before me is too worn to enable me to decide.
1. 1:1 «,! LATU8 S,,werhy. PI. 21. fi--. ~t'\-~n .
Shell ohlon.tr, rather smooth, olivaceous varied with white; front valve, lateral areas and posterior valve concentrically unduh;t. Iv wrinkled: central areas smooth, wrinkled at the margins. Length •Jo. breadth 10 mill. Girdle granose. (Soivb.}
J'm, -tn r»i-ti->r<> and Inner John* Jil., Centrnl Anit.i'i'-n, under Btonefl :it h»w water.
rliltnn rtiiiiil.tttt* Sown., P. Z. S. 1832, p. 58; Concl.ol. Illu^tr. t. !_'. 78, 1 I-. 144 ; Heechey's Voyage, Zool. p. \r>o, pi. 41, fig. 18.— REEVE, Conch. Icon. t. 19, f. 118; t. 20, f. 128, 13:}.— /W/,,,W//7oy, 1-niintnfn* < 'i'i:., MS.
( arjienter describes the interior and girdle from the type speci- ii, .11. tlni-: Posterior and anterior valves having 9, central valves 1 slit; teeth solid ; eaves moderate ; sinus \\ide. Hat. Girdle closely
imhricalcd with moderate sized solid scales, scarcely striated.
It is very like drinlnln* but havini: stronger sculpture. It goes through all the color variations of lonijicijnilxt. The >cah-s M-I-III to he smooth, but here and there are slight striolations from the dried skin.
I. c.\ i i:\ri.ATUS Sowerhy. PI. 21, figs. 47, 48.
Shell lonir and narrow, elevated, arched, the jugiun rounded. ( iirdle smooth, broad, thin, with imbricatini: striated scales. Muero central, elevated, the posterior slope >..nn what concave. Central :n. -a- sculptured with very close parallel liruhe, which pa.-s into wrinkles on the lateral area<. which ai'e -wolleii. Mud valve- con- centrically wrinkled. Interior: posterior valve having I <>, «-«-ntral 1, anterior valve '.» >lit>; teeth huiir, sharp, thin ; eaves moderate, not loi)Lr, but well develope»l ; not spongy. Sinus broad, deep, Miiooth. channelled. Length 17, breadth 7 mill.: divergence about
L02 . '
Inn, /' /,'.//,,> I.*I,i ml. I9, ,-tl.
I-' ll\'.< III 111
•WB., I'. / nch, in,.
l 15, REEVE, < onch, [con, t. •_'«., t: 180. /
< ri:. MS.
The single specimen before me is \vhiii~h, I UJH,
brown. tli.- girdle a-hen-hluMi. The >culptui.
more like thai «.!' /. th in/.ii,. ..,,,| adorn <
thing else, having exactly the same pattern, but not «pntc-
The girdle has conspicuously Mriated scale-.
The following gpeciee were referred liv Carpenter t,, €i L«-|«i«l<t- plrunis," but they arc closely allied to the j»n up.
I. DHJPAB Sowerby. PI. is, figg. 17, 48.
Shell oval, -niooth, asln-ii varied with whitish and Mack. < tral ai-cas smooth, posteriorly longitudinally suloulcatr : ant. vaK'c, lateral areas, and |>osterior area of the posterior valve uianu- lous. Girdle grunosc. Length 25, breadth 12i mill. (&•>
Inland Saboga, Bay of l*tununn, under .-tone.- on the shore.
Chiton d'i*i«tr SIJY., T. /. S. 1832, p. 58; Conchol. Illustr. f — KKI-IVK, (1onch. Icon. t. 18, f. 96. — Not 7,svA//o, -,/,/,,. Cai-penter MS. — Chiton jir<>/»-iit# K.KKVI-:, Condi. Icon. f. lol. — C. picus KKKVK, Condi. Icon. t. 25, f. 121.
The name has been suggested by the circnm-tanee of the central areas bein.ir quite smooth, while the lateral areas are covered with granules, i (1. B. Sowerby.')
The description given by Sowerby differs entirely from the spe- cies which 1 take to be the /.Wn/o/v/Js/</ <li.^,<ir of Carpeiit. r*| !/>.. and indicates a form very similar to Carpenter's L. <nlnui^ii.
( 'arpeiiter writes of the type of C. />r»/>riti* Rv. as follows : One specimen, smashed; " West Coast of America." I>r. A. Sinclair, K. N. This is exactly like the L''jii'l»/i/rni-ii* ii;.«/»ir, havin- lar--.\ smooth scales. Reeve's C. pictu i> also said by Cpr. to be a synonym for /. <li.-j><ir.
I. AI.AM-II Cai-penter. 1*1. Is, figs. ."il. ")•_'. 68, "» 1.
Shell resembling A. '//•*/""' - Pal" red-brown, irregularly streaked and maculated with darker, sometimes ornamented with white spots at the diagonal region. , I ugiim scarcely acute ; central areas and terminal valve> conspicuously granuloi;- : ftreafl irregularly
Ill' KCHNOCHITON,
uarted. the warts lohed. Mucro anterior, slightly Interior having tin- central valve with 1 slit, end valves 8-10 slit-. ii acute; sinus flat, very wide. (iirdle imhrieately Length !•">. breadth 7' mill.; divergence 110". < ( )/r.)
J'ltHIIIH'1.
danuti CIM:.. I*. /. s. 1st;:;, p. 24.— adatnsi* CPB., 1'. /. S. 1866, p. 'J74.
Tlie -hells which I have drawn in figs. .">1 -.">."> of pi. 18, seem to me to belong to this species rather than to /. <l!.<]>ar. They are described In-low. It must he understood that the more minute sculpture can be seen only under a compound ini<To>mpr <>r a very
Mul lellS.
The shell is oval, rather low, the jugum rounded. >ide->lop. s nearlv straight. Color dark olive mottled with lighter, or having large whitish tracts on some valves; the interior light blue, sutuml l>l<ite.-< u'liite. The central areas are closely sculptured with very minute pointed whitish granules, arranged in oblique lines at the juiriini (fig. 52) but toward the sides or pleura a system of shallow grooves with graniilon< inter-ridges curve forward from the diagonal line, as shown in fig. f>4, and at the left side of fig. of). The lateral areas and terminal valves have a coarsely reticulated pattern, formed by impressed zigzag or irregularly lobed impressions, over which a tine granulation extends (h'g. oo.)
The interior has 8-10 slits in the posterior valve, 1 in the inter- mediate valves (fig. .">:]). Teeth sharp, smooth ; eaves very narrow. The -jirdle was denuded of nearly all of its scales in both of the imens before me, but such as remain are large, solid.
Length 14, breadth 8-] mill.
I. TI:M D9CULPTU8 Carpenter. l'nfnjnr«1.
Shell similar to I,. « <l#n /.</'/; olivaceous, minutely variegated with
paler and darker color. Kntire surface minutely granulose : lateral
areas scarcely defined ; suture- spotted with white: mucro anterior.
rather conspicuous, the slope behind it com-avr. Interior a> in /..
'/ir.)
Panama,
Chil'in ili^mr ('. H. A I)., Cat. Panam.Sh.no. 373l part . — /.. />i'ln- kU <'ri:.. P. Z. 8. 18 •'. p. -J7-").
A variety is paler, tinged with rufous at the jugum.
l-< I IN. H III I
The outside of this shell so much iv-nnMe- id.
i/»»/-rs// that specimen- may have ln-« ii distributed m <i
Very few individual- \\ «• i v found.
on the type .-pecimeii, pr.ih.-iSily from 0116 of tin- other In
tlieonlv place in \\liidi tliev lit- /// *ifn, tliev are <|uite MiiM,,tli.
I. B08EUB Bowerbj. IM. 21, figs, I'.'. •'>".
Shell ovate oblong, siiHM.tli. roseate; back rounded; front \, and lateral areas of the intermediate valves loiigit mi inally. cent ral
areas transversely sulcate ; posterior valve with ctntral ap
eentrieallv sulcate. Len-'tli 1 7 ' -, hrcadtli 7 ' mill. fX /. nf J'/titu i ( 'iiniinu ) ; i'<i-ii<iii<lo Noronha (Chsdlei
r< rn i l.radley, in Mus. Yale College.)
r//. rwetw'SoWB., I*. /. S. l,s:}2, p. 58; Conr-h. Illustr., f. 1 I.—
REEVE, Con ck Icon., t 25, f. 119. — DESK, in Lam., An. s, \'
vii. p. 4!»s i not Cli'ifmi rntrn* lilainville, Diet. St«. Nat. xxxvi, p.
."».">:>. is-j.")f a species of Acanthochiton). — l*<-lino<-liit<>,> ,-,,*• »/.< <
.1/N. — I.«rhiiorh!t<m boof/ii HADDOX, Chall. Kep., Pulyphtr., j». \~t,
(1886.)
There is not the shadow of an excuse for the change of name made liy ETaddon, as Blainville'a prior C.roseus belongs to a -em:- uni- versally admitted to be distinct. The west coast locality is doulited by lladdon, but it is supported by specimens in the Yale College collection.
( 'arpenter gives the following notes on this species : Valves and plates very thin, snhdiaphanoiis; mucro median, little elevated. Interior: post. v. with 8, central v. 1, ant. v. 11 slits; teeth very acute; eaves very slender, moderately projecting : sinus large, Hat, high, scarcely laminate; sutural plates small, subtriangular. ( iirdle imbricated with minute solid, sim>»f/i scales, with bristles intercalated at the margin. The sutural lamina- are as .-mall as in /,>/>!»< ; an<l look like a mere prolongation of the in.-ertion plate- round the comer. The scales though normally shaped and arranged, are SO minute that Deshayes placed the species in the Tonicioid group.
lladdon writes of J. row •//.< (undei- the name /. bn<njii i, as toll
The locality attributed, on the authority of ( 'inning, to tlii- made the identification with it of a Chiton from 1-Yrnandn Noronha very doubtful ; a shallow-water \asnot likely to live in both
the Atlantic oil' IJra/il and in the Pacific nil' \\ • -; 0 lombia, \\illi 8
114 1-rilXoriHT'
the whole breadth of South America between. That tlie Chalk-Direr specimen is identical with the British Mu.-emn specimens is beyond doubt. May not the difficulty lind solution in the fact that the "I. of Plata," as it stands on ( 'inning's tablet in the British Museum, and to which Sowerby (Joe. cit.) addt d "W. ( 'olumbia" is really some island in the estuary of La Plata?
The above criticism was iirst suggested to me by the Rev. K. Boog Watson, to whom it gives me Lrreat pleasure to dedicate this species.
The single specimen in the collection is of a pink color mottled with creamy yellow, with an obscure yellow line along the jugmu, and with a pale spot on each side of the line on severed valves: there are also several irregular dark patches; the posterior valve is deep-rose below the umbo. The girdle is mottled brown and white, there being a white patch sit the junction of each valve.
The shell is long, narrow, and arched, anterior and posterior valves with fine concentric ridges ; the umbo of the latter is prom- inent. The intermediate valves are apparently smooth, but really with extremely delicate longitudinal strire; the lateral areas are characterized by wide ridges. The ligament has stout, tall, imbricate scales.
The three specimens of this species in the British Museum are pink and only slightly flecked with white, no black or brown spots, and in two of them the central areas have concentric lines like those of the lateral areas.
o. Qroup of I. pwictulatissimus.
Small species, having the central and lateral areas closely and minutely granulated. No riblets. West Indies and South Ameri- can coasts.
I. i-Ai-iLLOSUS C. B. Adams. PI. 21, figs. 40, 41.
Shell small, oval, carinated on the back, the side slopes slightly convex; surface not divided into distinct areas, apparently smooth, but under a strong lens seen to be closely and evenly granulated throughout; color whitish, closely mottled with olive-green; or olive-green or olive-brown, with or without snow-white spots.
The lateral an-a< are not raised, and are sculptured precisely like the central areas, from which they are defined simply by an incon- spicuous diagonal ridge. The posterior valve is moderately eleva- ted, the umbo central, rather acute, posterior slope concave.
UNO, IN i.
Interior \\hili-h ; :uiti-ri«>r valve bavin itral I , .
valve !» >lils; teeth .-harp, liiin :in<l .-inonili ; . ( lirdle naiTo\\ , alternately olive In-own and \\ In
\vr\ minute, imbricating striated .-rule-.
Length -S', breadth ."> mill.
Lengtfc -V. breadth •> mill.
JuiH'iini (Adams i ; Murt-n, X» \<ni<> l\<u //,/»/ A llrmpliill).
Chiton papillosus Av.< PI-.H-. ii.,.-t. >.»<-. N. II. i^i:>. [..!». — C.
^opi^/oatw SHUTTLW. Hern. Mitthcil. l-s">-'), p. 77.- / l»il>il!n«u« DAI. i., (atal. Mar. Moll. S.-K. U. S., in Hull. :J7, I Nat. Mus., p. 17L'.
This is the smallest of our Florida or West Indian I-rlmoid-. It lias much the same sculpture as the small Leptochitons, being uni- formly granulated and having the lateral areas very indistinctly defined. It is readily known from other Ischnochitons by these characters. The original description is as follows :
Shell small, wide ; greenish, closely maculated with whitish and black; papillose; areas separated by a slender riblet; girdle very finely scaly, alternately greenish and white.
Length 5'25, breadth 3'25 mill.
I. ITNCTCJLATISSIMUS Sowerby. PI. 21, figs, oo-
Shell oval, moderately elevated, the dorsal rid^u bluntly angular, side slopes nearly straight. Surface apparently smooth, but seen under a lens to be minutely and evenly granulated all over. Lat- eral areas ill-detined. Flesh colored, speckled or dotted all over with light brown, and often maculated on some of the valves or along the dorsal ridge with dark brown.
Lateral areas demarcated by a very low and obtuse ridge, obsoletely sculptured by the intersection of two series of obliquely radiating curved impressed lines; central areas similarly sculptured by obliquely longitudinal lines. Umbo of posterior valve in front ot' the middle, the posterior slope concave. Interior bine-white, having 9-12 slits in the end valves, 1 in the median valves; to-ih acute: eaves moderate ; sinus wide, flat. Gird!. 1 with -olid, flat-
tened, striated imbricating scales. Length 17, breadth Id mill.
Bay* of Callao, Mexill<me«, Ljiufj" on dead shells, 6-10 fins.
116 ISCHNHCIIIT. .\.
Ch. /miirtu/titi*#tiHHit Sow r,., P. Z. S. 1832, p. 58 ; Conch. Illustr. f. 9, 26; Moll. Beechey's Voyage p. 14!>, t. 40, f. 3, 3.— RKKVI:, Conch. Icon. t. 20, f. 129.
Tiic typical form of this species is descrihed ahove, and figured on my plate. It is characterized by the almost effaced but even granulation, which is the same on both central and lateral areas, although differing in direction ; by the minutely freckled color pat- tern, etc.
Sowcrhy mentions a white variety with a black border and some- what varied with black. This form I have not seen. It has been illustrated by the figures in Captain Beechey's Voyage, H. ^1. S. 'Blossom,' and fig. 9 of the Conchological Illustrations. The latter figure I have copied on my plate.
I. IMITATOR Smith. PL 21, figs. 29-34.
Shell elongate-ovate, moderately elevated, subangularly arched at the middle, dirty white. Valves narrow, with a single notch on each side, exhibiting small, slightly raised lateral areas, which towards the margin have a few transverse strong grooves or marks of growth. Front margin sloping very slightly on each side from the middle in a posterior direction ; hind margin straight. Sculpt- ure consisting of close flat granulation, exhibiting a somewhat serial arrangement. Lamina of insertion [sutural plates] very thin, with a wide sinus between them. Anterior valve sculptured like the others, with fourteen fissures within, the thirteen teeth between them being sharp and straight edged. Posterior valve with a cen- tral mucro, from which there is a faint ridge on each side to the lat- eral extremity, also marked with concentric lines of growth at intervals and with the inner marginal fissures twelve in number. Scales of the mantle minute, imbricating, ovate, arranged length- wise ; under the microscope they appear very coarsely transversely grooved. Length 11 mill.; diam. of fourth valve f> mill. (Smith.')
Tom Bay, Patin/ntiln, on the shore.
Ch. (Isrhnor/nt,,,, ) unitotor E. A. SMITH. P. /. S. 1881, p. 35, t. 4, f. 13.
6. Groii/i i if 1. nun i it a*.
Surface evenly, minutely granulated, the lateral areas having radiating riblets. (iinlle scale.- nearly -niooth. .Japan, etc.
BNOCHTP 117
[. COMPTUS < "Mild.
Shell small, thin, cllipt ical ; Lrn-.-n ,,r ~r;iH, t. Ci •.•.|u«-nt 1 y (l(ittc<l or maculated with \\hiti-h or yellow. Valves -ln.rt, tic valves radiatcly riblx-d and punctate; central area! qtllDI
punctate. Lateral areas elevated and sculptim d \\ith I
ting grooves. Interior given, (iirdle narrow, imhrie;it.-d with small elongate*! grooved scales. Length 1 .">, diani. 10 mill. < Old.) Ootinut, J'l/xtn ; llnn'm uml /,/'//- A'/// /x. /Slim;,.
C. (Leptoehiton) wnn/itn* (»<>I:M>, I'roc. Host. Soc. N. II. vii, p. 163; Otia, p. 117.— hch. <'<nn/>fn« CJPB., J/\
Carjientcr writes: Entire surface punctate; central areas having the lines of points either parallel or bending toward the acute juguni ; lateral areas having small radiating \vrinkl<-s, at fii-t :i \<> \ in number, then splitting into 6 to 8. End valvo havin-j- in deli- cate, hardly apparent radiating wrinkles. Mucro slightly in front of the middle, slightly elevated. Interior: posterior valve with 13, central valve 1, anterior valve 14 slits; teeth acute; • moderate, acute; sinus wide, flat. Girdle having large, solid imbricating scales, sometimes very slightly striated. Length 1 7 , breadth 10 mill.; divergence 120°. Philippines, Mus. Cumin_ 11. Dr. Gould strangely placed this species in Leptochiton. although the scales are as large, solid and regular as in Chiton. The above diagnosis is written from Mr. Cuming's beautiful speci- mens, which are broad and externally curiously like the vein Chiton (var.) patulus. In the typical specimens, the striulation of the scales can seldom be seen, having apparently lived in ex; situations. The variation in color is extraordinary, being (a) densely clouded with olive; (6) light ditto mottled with dark and lilac; (f) four central valves chestnut, the rest olivaceous; (d) brown with olive, with broad white streak down the centre ; (e) light reddish-chestnut mottled ; (/) ditto, shading into oli (0r) sixth, seventh and part of eighth valve dark olive-brown. rest light ashy; (//) the whole light ash. The sutures are alwaya regularly spotted, as in T. jtseudodentiens. In the typical specimen examined there were only eleven slits in the terminal val\
I. LEPIDUS Gould. Unfyured.
Shell small, elliptical, roof-shaped, yellow-irreeii >tn-akrd with olive; front valve semi-circular, radially striated; posterior valve crescentric, beaked, radially grooved behind and longitudinally in
118 I-- IINMI mi. P\. .
front; lateral arras elevated, sculptured with 6 radiating sulri : central areas imbricatelj sulrate. (iirdle narrow, handed with olivaceous, covered witli minute scales.
Length l:J. breadth !» mill. (G7d.)
Interior: terminal valves with about 14, central valve.- 1 slit; teeth very acute, but a little serrated at the edge. Haves large; sinus narrow, vaulted, scarcely laminate. Girdle irregularly imbricated with transverse, solid, neatly smooth scales. (Cpr.)
China Sea, Lot. 24* N.
Chiton (Lepidopleura) !f/n'<ln8 GLD., Proc. Bost. Soc. >". 11. vii, p. H>4 ; Otia, p. 118. — Ischnochiton /c/inlus CPR., MS.
The girdle scales are those of Lepidopletirus, [—Lepidozona] except that the imbrication is irregular. The species is remarkable for the narrow-, arched sinus; and for the slight serration of the insertion plates which are yet normally sharp and protected with broad eaves. I have not been able to re-examine the type since I matured a plan of arrangement for the sections of the genus. (Q?r.)
I. PBTALOIDES Gould. PI. 23, figs. 92, 93.
Shell small, delicate, elliptical, roundly arched, very slightly car- inated, the valves not beaked, of a pale lemon-yellow ground color, reticulated along the centre, with delicate, angulated, pale-violet line-: these areas are also rugosely lineate-punctate longitu- dinally, especially toward the margin ; lateral areas very prominent, riiiro-rly granulate, and with about four, fine radiating stria? ; pos- terior valve acutely umbonated and crossed by an acute, tran- rib. Margin cream-colored, very finely granulate-imbi ;
(Old.)
Interior : posterior valve having 9, central 1, ant. v. 9 slits ; teeth acute; eaves acute, hardly spongy ; sinus very widt •. short, smooth. Girdle imbricated \\ith flat, scarcely striated scales. (Cj>r.)
Length 12i, breadth 10 mill.
Kan 1 1 1 <in>l OaJnt^ SainhrirJt /.«.
C. /»t« /•"''/'>• <1 i.i».. I'r«'c. liost. Soc. N. 11. ii. p. 144, July. lM'i; t . >. Kxpl. Kxped., Moll. SI... p. ::•_' : Otia Concho)., p. (i ;
C. (Luciu) pdu/n!if>:< ( \\.\t., ( Mia p. L' 4 '_'.— J.n/Ji tfru.< /xf.i/n!,/, .< 1^1 .
Amer. Journ. of Conch, vii, ]». 194. — Itchnochiton i»inln't<l, .< Cv\\. MS.
The scales an- rather lar.L'r for the >i/c of the shell, but thin, sprciiin-n- have sometimes an af>prarancr of minntr >triula-
i» ii \< » 111 i 1 1!>
tion, from tin- contraction of tin- epidermal film. I >r. Gould
mi-"d that tliU ipecitt «mirht t<> lie :i Lucia, i
the Pacific Is.; hut it is a normal l-chnochiton in all respects
except the non >triation of I he scales. < ( ///•.)
I. m-< i i.i-i i > ( 'arpeiiter, n. sp.
Shell small, oval ; juu'iim acute; miicro me.lian, rather elevated; :i>hy, maculated with olivaceous. Entire surface minutely gnmu- lose ; central areas having about 10 distant, acute, subparallel lira-, sometimes siih^ranose, the interstices wrinkle-decussated. Lateral areas scarcely raised, ha vim: distant, small, much raised Drains, Mih- radiately arranged in --4 scries, the end valves having 16-20 such series. Interior: posterior valve having 7, central valves 1, ante- rior 10 slits; teeth rather obtuse, roughened but scarcely pectinated at the margin. Eaves small ; sinus small, deep, smoothly laminate. Girdle rather regularly imbricated with decidedly transverse, con- spicuously striated scales. Length 11, breadth 6 mill. ; divergence 120°. (<>/•.)
/ Hong Kong (Stimpson, N. P. E. E.).
" Chiton f pulcherrimus Sby." GOULD, MS. + C. (Leptochiton) craticulatus GLD., Otia, p. 117, pars. (Cpr.).
The shells forming the five species, pulcherrimus, craticulatus fcul- tratus, bisculptus and asperior were included by Dr. Gould under the first two names. They need a careful examination of the details of sculpture, as well as of the mantle scales, in order to sep- arate them. Of these pulcherrimus and bisculptus have the striated scales of Ischnochiton ; craticulatus and cultratus, the strong, smooth scales which belong to Lepidopleurus ; and asperior is intermediate between Trachydermon and Cha3topleura. The decided; rugosity of the insertion plates and short eaves of this species form a transition toward Chiton. The whole group appears to have a slight lamina at the sinus, marked off by a slit from the sutural wing. (Qw.)
7. Group of I. interstinctus.
Small, finely granulated shells, the lateral areas radially ribbed. Scales striated. Species of the west coast of North America.
I. IM KKSI IN. n s Gould. PI. 11, figs. 40, 41 ; pi. 21, fig.
Shell OVal-oblong, rather elevated, the dorsal rid;:*1 ohti: keeled, side slopes nearly straight. Surface apparently smooth, but
1-" I-' !i.\<M mi-ox.
under a lens it is seen to be very minutely punctulate, the indistinct lateral areas hein.i: ohsoK-tely radiately lirate also. Dark reddi.-h, mottled with liirlit on the dorsal ridge.
The lat.-ral arms an- >carcely perceptibly raised and besides Ix-in- microseopieally punctulate like the rest of the surface thev have low radiating ribs. al)oiit 6* or 7 in number. Central areas evenly punetulate: end valves punetulate and radiately multilirate. I'ml.o ,,f posterior valve in front of the middle, rather elevat. d. Inside: posterior valve with ll\ anterior valve 10, median valves 1 slit ; teeth acute, eaves moderate; sinus wide, flat.
(iirdle densely covered with small, suboval, delicately striated* scales. Length \^>. breadth 8 mill.; divergence 110°.
Xifk'i ll'irhor mnith t<> Monterey and the Santa Barbara la., Cali- fornia.
Chiton interxtinrf,,.* GLD., Proc. Bost. Soc. Bost. N. H. ii, p. ] \:> : M.,11. T. S. Expl. Exped., p. 315, pi. 23, f. 423 ; Otia, p. 230, 2 1_\ —Ischnnr/iit'tH i ,itcr*liii<'tn* Cn:., .1/N. isj)!, and DALL, Proc. U. S. Nat. Mus. 1878, p. 331.
This is a small reddish species, characterized by the fine pun ela- tion of the whole surface and the rather coarse but low radiating riblHs of the lat.-ral areas and end valves. The sculpture is not well shown in ( iould's figures. It is drawn from a specimen before me in fig. 39 of pi. LM, representing an enlarged half-valve.
I. M:\V( -»MI;I Carpenter, n. sp. Unfigured.
Sh.-II small wide, tumid, with obtuse rounded ju<:um. Mucro median, rather elevated. Ashy or olivaceous, ele-antly clouded; central an ;i~ and entire surface -raniilated, the granules being <|uincuncially arranged, close and regular; lateral areas scarcely defined, having abou! 4 lines of tubercles which are hardly elevat. d. Posterior valve having about 30, anterior valve 40 such lino. Inte- rior: posterior valve having 12, median 1, anterior valve 11 slits; teeth acute; eaves apparent ; sinus wide, short, scarcely laminate, (iirdle imbricated with large striated and rather regular s-ale>. Length
83, breadth <i mill. : diver-enee 100°. (Cpr.)
Sta. Catalina Is. (Newc.). The phm ,,f s Milptuiv somewbal resemblee that of /. interetindus,
though coarser and diflJ-n-nt in d.-tail. It resembles /. rod '» Illost ' :•! in the rounded U-ak ;md larger «cales
(Cpr.)
BVOOHFP 1 -J I
1. i; \ 1. 1 \ N~ < 'arpenler, n. sp.
Shell r;itlirr large, \\ide, elevatrd, tin- JULMIIII ftCUte ; "li elegantly radially streaked with brown. Interior |»|, <.\Jth
two In-own rays. Valves delicate, Hat, product d in the -inn- in front : mucro in front <>f the middle, .-eareely elevated ; entiiv >ur-
face quincuncially granulated ; lateral areas scarcely defined. ;u,d
with the end valves ohsoletely sublirulate. Interior: pi,.-t- valve having JMO, central valves 1, anterior valve ID 11 slits; teeth acute; eaves small; >imis wide, short, scarcely laminate. Girdle regularly covered with solid, coarsely striated, moderate sized scales. Length L'l, breadth If) mill.; divergence 110°. (( ',
Monterey, Cnlijoniin.
The internal color-rays are seen in all the dead valves; the external painting resembles Mo/xtl'm vespertina. The sculpture is on the plan of/, mterstinctus. One central valve of one specimen, on one side only, had a second slit. (Q>r.)
8. Group of I. scabricostatus, I. SCABRICOSTATUS Carpenter. Unfigured.
Shell small, orange colored, elevated ; valves gothic arched, jugum acute. Entire surface very closely granulated ; lateral areas well defined, with 3 subobsolete, radiating series of large granule.- : beaks scarcely apparent; umbonal margin slightly turned inward, and having dark spots giving a false appearance of teeth. Central areas having separated longitudinal series of narrow, subobsolete riblcts, furnished with large granules. End valves having similar radia'inir granulous riblets. Umbo of posterior valve scarcely cen- tral, little projecting. Interior: sutural plates separated by a large flat sinus; insertion plates subobtuse, the end valves having 1"-1_, central valves 1 slit; eaves moderate, subconspicuous. (Jirdle wide, closely clothed with imbricating, elongated, transvei>« 1\ striated scales. Length 73, breadth 41 mill.; divergence 1
(Cpr.}
Catalina Islan<I, California, in lO-'Jo fms.
Le]iu1n/>f''ii,'n* anibr'icttxtuhi* Ci-i:., Hep. Brit. A.«so. Adv. 8 isi;:;, p. 649; IVoc.Cal. Acad. N. S. ii, p. -iVl.—Mm,,- iW-
costatu* ( 'i'ii., J/&
The sinus has a thin, smooth lamina separated by a slit on each side from the sutural lamime. It is a small, arched oraii-.
with rows of prominent granules over a shagreened surface, '
l-i'llNn* HI!' >V
N i ii N- < 'arpenter. I'n >/" /'"'.
11 small, whitish, tinned \vitli rOMafte; valv»- gi.thic-arched,
mi suharute; entire surface minutely irranulnse: lateral
-picii'Misly il. -lined, having strong diagonal and sutural
; with well projecting rounded grains; end valves hav-
ini: -uhohsolete radiating riblet>: central areas having about s di.—
taiit, raised subgranulose longitudinal rihs on each side, the rih<
at the jugum : inter.-ticcs latticed with suhradiating rihlct-:
umhnnes conspicuous, the uinhonal margin deeply toothed by a wart-
bearing ril>. the teeth 8 to 10, obsolete toward the jugum : margin
• ly intortrd. Tnibo of posterior valve submedian. slightly j >ro-
•iiaririn elegantly pectinated. Interior: sinus large, Hat.
: rate : insertion-plates acute, broadly uniiissate. end
••s having about 8 slits ; eaves conspicuous. Girdle having lar^-
riated scales. Length 61, breadth 2-1 mill. ; divergence 90°. (Cj^r.}
,! /xA//td, 20-30 fins.
veredentiens CPR., Rep. Brit. Asso. Adv. Sci. p. 'il!*: I 'roc. C'al. Acad. Sci. iii, p. 211.
A small arched species, sculptured like /. mertensii, but with two 8, one of which dentates the sutures. The girdle scale- rat her large, flattened and striated, as in typical I&knochiton.
I. BBRRATUB ( 'arjicnter. Utifiyured.
Shell small, ashy, dotted here and there and especially at the suture- with olive, sometimes spotted with red ; oval, suhdepressed, the sutures indistinct; entire surface mo.-t minutely granulated: lat'-ral areas strongly defined, provided with two to five very wide, obtuse rihs, no interstices; posterior margins elegantly serrated. Central areas having about 12 acute parallel ribs on each ride; juLrum obtuse, scarcely uinhonate: with subradiating latticing ribs. intei>tiees impre.-sed. Mucro median, obtuse. End valves having about 20 obtuse rihs, like the lateral areas. Interior: median valves bifi>sate, end valves with about !> .-lit-. Sutural plates i liirdlc imbricated with large, scarcely >triated .-cales.
Length 8'. breadth ~> mill. ; divergence 115°. (<>r-)
Caj" >V. /. ' 'fiwritin.
Ischnochtion terratut CP&.I Ann.iV Mair. Nat. Hist. (3) xiii. p.
UN... in;.
I. \i 1:1 OTINCT1 - < 'arpeiiler, n. |p, ( 'nj
Shell resemblili (f, but the lateral AfMI
Scarcely defined, radial and Ion-it udina! Kntire surface equally granulated. < )ran-e .-potted \vitli Interior: posterior valve having 11, central \alv<- I, anterior l.'J.-lits. Len-th «;.. breadth \ mill.; diver-ence IIHI . r//r.)
( ''ilnlinn, Ixluiitl, ( 'nl.
Thl8 Species is known from Tr.jln.rti* by the valvis not beini: beaked, and by the large striated scales of the margin, which
nilile tho>e of /. scabricottatut. (Cpr.) I. DECIPIENS Carpenter, n. sp. t'njnjured.
Shell exactly like /. /irrfinii/'ifii*, hut reddish, rK-vatod, the JIILMIID acute ; scales of the girdle small, striated.
Length 15, breadth 7-j mill.; divergence 105°. (Cj>r.')
This very pu//lin,ir shell differs from /. *!nn(lriit<itii.« in it- normal sinus and smaller scale- ; I cannot help suspecting that \\lnn moi'e specimens have been examined, it will be found that some chara-ier-. generally constant between species and even groups, are occasionally variable in the same speeies.
I. CORIM <; \ it s Carpenter, n. sp. Unfigured.
Shell similar to Ch. sanguineus in form and varied coloring ; entire surface granulose; central areas having impres>ed punctate wrinkles, hardly lirate ; lateral areas strongly longitudinally corru- gated. Interior: posterior valve with 8-10, anterior valve i central valves 1 slit. Sinus wide, flat. Girdle thin, covered with very close, very small striatulate imbricating scales.
Length 13:], breadth 7 mill.; divergence 90°-100°.
( 'otalina Is., beach to 40 fms. (Cooper, Cal. State Coll. No>. 1 • 1070,1074); Todos Santos Bay (Hemphill), California.
Differs from Stenoplax samjuine.ii* in sculpture as well as in the plan of mantle-ornamentation. A specimen from Todo- Santo- Uay (under a stone between tides) collected by Henry Hemphill, is about the size of limactfornil* from Ma/atlan, and it would natur- ally be so called; the sculpture, however. i> >« -n-ibly ditfi-rent, both from that and from /'<///</.>•. The central areas are minutely, the juir;d areas very minutely, wrinkle-punctate, wrinkle- an-jular. irregular; lateral areas moderately dcfineil and el and,
llM ISCIIN'M HI TON.
ther with the end valves, irregularly. suhconccntrically and >t ron-jlv c,.rni'_rat( <1. Mucm median, planate. This -pr<-i«- i- a
ii/iij- in furin, but & true Itchnoehiton in its imbricated scales,
which arc. bowever, extremely minute. This specimen is n-iruhirly arched. much less elevated than the type, with which, however, it agrees well in particulars. Length '_M, breadth !» mill. ((
I am unable to see why this should not he considered a .sVr///y/A/./-, imles- it !>e on account of the smaller girdle scales; but, as I have not seen specimens, I deem it be.-t to leave the specie- when- ( 'ar- penter placed it.
I. SUBCLATHRATUS Pilsbry.
Shell suhrotund, depressed (at an angle of 130°); brown-olive; valve- very wide, the margins lobed, interstices nearly straight. Intermediate valves granulated at the dorsal ridge and more or [em all over, having two strongly tuberculate ribs, one diagonal, the other in front of the suture; lateral areas small, granulate; central areas having four longitudinal bars on each side, the bars tuher- culate, interstices granulated. Front valve having about eleven rounded, suhtuberculate radiating ribs. Girdle very wide, having close small scales ; valve-margins simple, the anterior having 9 slits.
Length 41, breadth 3 alt. -5 mill.
, under stones.
Lepidopleunu rluthrnhi* CPR., Mazat. Cat., p. 1 05 (1857) , /W»//o- r/tifhr'ifnx (Vi:.. J/& — Not Cli. r/'itlirntu* Ri:i:vi:, Conch. Icon., pi. xviii, f. 113 (1847.)
I have not seen this species, the name of which ha> been already used by Reeve. Carpenter write- as follow.- :
One very small specimen was discovered on a stone to which a Crucibulum had been attached, beautifully perfect except in the loss of the anterior valve. A dead anterior valve was found of a much larger specimen displaying a marginal structure like that of /,. The shell is remarkable for the Mrong bars across the central area-, and the stout rows of tubercles which run, tin-
•-nally. the other along the inteistitial margin. The mantle is v.-i-y hr..ad and crowded with minute Males. '/"*.)
I have no opportunity of re-examining the type of this minute
shel. bether the very minut n-e sti-iated. If so, it
mii-l clotdy re-.Miihle the young of /. . The jiaucity of
lr< ll\<" III i genuine Ttchnochitont in the Gulf fkuna i- n-mark:ih|'-.
so many .-prcie.- ;nv found I'urtlirr north. < '///•. l/> Section Lrj,i'iln;nnn Pil-hrv. I 3
LepuJopfetmi* CARPENTER (Table of lirgular chiton- DM i.. Proc, r. B, Nat. MII-. 1878, p. 881, type / Mdd.
\ ,| LtpidopleuriU of Ki--<>, Hi-t. Nat. Kiir. M«'-rid. iv, p. iX'Ji!, nor of II. iV. A.ADAMS, L 858, HOT of CARPENTER, Ma/at.
Cat i
Valves having sharp but somewhat, rugose and tliick in>ertii.n teeth, and Mypically) the sinus is delicately toothed within. (Jinllr covered with convex scales, usually snioot liisli. Type /. mer\>
This section diflers from Ixcluxx-hitnn not only in havini: the gir- dle scales convex and smooth or hut slightly striated, hut al>o in the toothed sinus. It is, however, an artificial Lrrouj>, the species being more closely related to a number of diverse /.W///W//Vo//x than to each other. Numerous transitions from the smooth convex scales to tlat striated scales occur, the variation in degree of stria- tion being considerable in some species. This section in its present limits is therefore merely a temporary expedient for convenience in identifying species. It should rank as a section under Minorhif<>n s. s., rather than under Isehnoradeia, to which group these species have no especial affinity. The status of the name Lepidopfatnu has been discussed on page 2 of this volume.
I. MI- UTKNSII Middendorff. PI. 26, figs. 20-26.
Shell oval, elevated, with angular dorsal ridge, and straight -side- slopes. Varying in color from orange-red to claret-red, or even dark red-brown, and either unicolored or speckled and blotched with white.
The lateral areas are elevated, and sculptured wiih radiating rows of elevated pUStuleft Standing upon a smooth, alm«»t tlat ground; the pustules of the SUtura! row often irregular. Central area- hav- ing acute, narrow, parallel rai-ed riblets, the intervals bet ween them regularly latticed across, except at the dorsal ridge, where the rihlcts have a tendency to diverge, and the CTOBS hatchi letfe
End valves radially pustulo.-e. Mucro central, low, tlat and incon- spicuous.
Interior white or blue-white, the median valves when det-ached showing broad red-brown ray.- po.-teriorly. the end valves with
[81 ll\. H II1TON.
:,»• same color. Sutnral plates low ; sinus flat, angular, tinely toutheol. Anterior valve having 10-11, central valves 1, po>teri»r valve 10 slits; teeth rather >hort ami obtuse, and u.Mially di>tinctly
belted : eaves rather wide.
Girdle tinn. compact lv cover. d with regular, solid, oval, >hinii>g scales, which are usually smooth, but frequently are superficially or
telj striated ii-. 22, Length 85, breadth L'l mill. |.e,,LMh :'>*. breadth 2-°, mill.
Sitk't iifinl/i to Mnnh-i'ci/, ('of !j'"r/i in.
Chiton \ Mi DP., Hull. Acad. Sc. St. IV-tcrsh. vi. p. 118,
lsl«i. — Chiton (PhcenocJiiton, Ilmnm-hiton, Stenosemus) merl Mi 1.1... Mai. Ro.-, p. :U, 125, t. 14, f. 1-3, 184?*— J*pfoeAiton
mertentii II. £ A. AD., (Jen. Kec. Moll, i, p. -47-">. 1>">4. -J,rj,i'il>,- tM )m-rten*ii CPR., J/*S., and DALL, Proc. U. S. Nat. Mu-. 1 >7V. p. 8
This species may be known by the more or less red coloring, the shining convex oval scales of the girdle, which are usually alnn»t smooth, and by the strongly developed sculpture. Attention has alr«-a'l v been directed to the similarity of the Ch&topleura '/'""/"" «>f Cpr. i p. '•}} i, which dillers mainly in its spar.-ely hairy girdle.
- iihrrn examples of this species are larger and more frequently variegated with white than those from the northern part of its range; and the girdle scales seem to be more distinctly striated. They seem to be almost or entirely smooth in mo>t northern speci- mens as far as my material shows; and I do not doubt, that Car- penter's figure (pi. 26, fig. 23) was drawn from a specimen collected north of San Franoisoo. In almost all of the specimens from the smth which I have examined, the scales show a delicate striation \\hen illuminated from the side, or at right angles to the direction of the stri;e. This is shown in figure 2U, drawn by the author from a Monterey specimen. The sculpture of the valves is peculiar ; the ! area ha- diver_'inir line, with smooth intervals. This is always most pronounced on the seconil valve (Hg. lM . the other valves often having the line more nearly parallel, and the intervals not all smooth. This is shown in fi_r. 25, repir-entiii- a fourth valve; but in smm- specimen- the divergence is even le>s pro- iiMiincrd than in this. The pustules upon the front valve occas- ionally become soldered \> Uto riblets, but those of the tail val mill disti:
l-< H\M. IN |
I. . OOPEBJ ( larpenter, n. >p. I'l. •_'»;, figg. -j;
shell oval an.l elevated, wiili angular dona! i side-slopes, Sculpture like Lmerientii. ( 'oh.r <,li\ae« ,,n.~, or dull
earthy In-own, indistinctly clouded IM..IV or ten \\iili liirht blue,
especially upon the side areas. The lateral areas arc iai-<d, and
hear irregular n«ws «>f rounded pustules, the young bavin- four : the adull (I to 's. A >troiig lens reveals a line, suhol»ob-te irranula- tion of the nearly Hat surface between the pustules. The central areas have a line hut distinct and even radial striation, over whieh run acute narrow raised threads parallel to the dur.-al rid-c; upon the ridge these threads are seen to be more or le.-s divei-ifim:, specially ii])on the second valve. The end valves are radially ridged, the ridges bearing elongated pustules, or showing - where such pustules have been. Mucro low, flat.
Interior bluish, the valves marked under their innbnnes with dark olive. Head valve having 11, central valves 1, tail valve 11 >lits ; teeth roughened but rather sharp; eaves wide, dark, minutely punctulate, but solid, not spongy.
( iirdle compactly covered with small imbricating, deeply striated scales (fig. 28). Length 40, breadth 24 mill.
Xmt.tti ('rn: and Bolinas, California.
This species closely resembles 7. mertei>*ii in shape and sculpture, but it differs entirely in the smaller, distinctly striated or grooved scales, in the sombre coloring both outside and within, in the closer pectination of the inter-liral spaces of the central areas, and in the more developed microscopic granulation of the lateral areas. It cannot be claimed that all or any one of these characters is invari- able, but the balance of them taken together, seem to indicate that differentiation has proceeded to a stage we may call specific. The following species is allied to this in coloring, but differs sufficiently in sculpture, a< well as in the girdle-seal'-.
The details of sculpture and the scales of all three >p drawn to the same scale. The third valve of/, cooperi is >h..\vn in tb-s. I'D, :](). It must be remembered that the valves behind this, and usually even the third, have less markedly divergent -culpture than the typical form here shown.
The specimens herein described and figured are from Bolinas, north of San IVanci-co, and since no diagnosis has been published hitherto, thc.-c will be considered the typical specimen-. Carpel specimens were1 from Sta. Crux.
1-JS [8GHNOGHITOK,
I 8INUDENTATU8 ( 'arpcnter, n. sp. Unfiyured.
Shell oval, much elevated, reddish : juLTum acute-; nuicro median, Iv elevated: entire surface minutely irranulose. Central - lia\ mi: about 12 Bubparallel bare, Which pectinate the i'n.nt marLriu. their iutn u--ated : lateral areas havini: '5-4 irran-
OSC radiatini: lira-, the anterior valve With 26, posterior valve 24 such Lim. Interior: anterior valve with 10, central 1 , posterior valve l) slits; teeth acute; eaves conspicuous. stibspongy, crenulated by the sculpture ; sinus wide, short, laminate with ahout «; teeth. Girdle having moderate si/ed, wide, conspicuously striated, rather iarly imhrioatiDg scales. Length 15, width !•• mill. ; diver- gence 100°. (fyr.)
Monterey, Cti/ii'u-uin.
This shell has the color of /. mertensii, nciirl/ the sculpture <•!' /. f.cctumi.itn* and the normal scales of this «rroup. Like /. /•"/"- . it htis the denticulate sinus of Chiton. (Cpr.)
I. CLATHRATUS Reeve. PI. 26, figs. 31-'U.
Shell oval or oldong, elevated, the l>ack carinated : >ide slopes i\\\ : lateral areas and end valves radially grauulate-lirate, cen- tral areas latticed. Color dingy yellow, clouded with black, or rarely unicolored yellow or olivaceous.
The lateral areas are raised and sculptured with about 5 rudia- atin_r. clos-ly and conspicuously irranose rihlets. the posterior rib wide or hilid : stroiiirly [icetinated alon<_r the sutuial (d^e. Central area- havini: longitudinal narrow bars parallel to the doi>al i
d l»y liars of almost e<|iial prominence vertical to them, prodiieini: the effect of a grating. Mucro depn-s-ed.
fnterior whitish, with olive or leaden ra\s under the uinboiie-. Sinus flat, denticulate; anterior valve having 11 -I'-', central valves I, posterior Valve 14-HJ >lits; teeth rather sharp, but not thin
id;
Girdle Compactly covered with very convex scales, which aie ob-oletely striated. ,jtli 27, br.-adth 17 mill.
Length 84, breadth is mill.
and Son to I.> Pout, /
i-i IIN«H mi'
1'lu'ton rfittlu-'itu* III I A i . < '..nrli. Iron., I. 18, f, US, A pi — Le}>i<l<>l>/''iin<x jn-clinntint ( Yi:., lYor. (':ilit';i. Arad. \ I'll, ISIJ."); not /,. jici'tiniifn* ( Yi:. in lit it. AjfO, Hep. i
/. OOOp0Tt CPB.), ii«>r f'/iilni, /,<'<•/!, iatn.< Sou i RBY, altOai (7; //OH (jmt., j>. I'.l ).— Li'indnjtlcnriiA i,,'ctiinilutu.<< < Yl:. .!/>'. and of Ainrriran collectors and writers.
Carpenter's diagnosis in Proc. Cal. Acad. Sri. -eems to have included both this species and /. roopo-l, but he afterward distin- guished tlirni upon receipt of better material, and re-Darned the prev- ent form " pectin tilatnu."'
This species seems to replace /. mertensii south of Monterey. It is a dingy, lusterless shell, resembling mertensii in the shape of tli<- girdle scales, which are, however, not so bright and clean in the dalhrtitns. It has decided riblets on the lateral areas, and the lattice-work of the central areas is strong and much less finely cut than in cooperi or mertensii. From /. cooperi, the different scaling of the girdle, as well as the sculpture of the valves, separate thi- form.
The second valve has divergent sculpture on the dorsal ridge, but upon the other valves the riblets are parallel or nearly so there, and the interstices are latticed.
I. COREANICUS A.dams & Reeve. PI. 27, fig. 50, (enlarged.)
Shell ovate, rather elevated, terminal valves and lateral areas of the rest radiately grooved, interstices convex, peculiarly grained, grains prominent, round, solitary ; posterior terminal valve um- bonated, extremity radiate, small, short ; central areas longitudinally very finely granosely ridged, interstices between the ridges hollowrd ; lateral areas blackish-green, grains yellowish, central areas yellow- ish blotched and variegated with black ; ligament finely granosely coriaceous, tessellated dark and pale green.
The sculpture of this species is not much unlike that of C. lurtdus ; still it is distinct, and accompanied with a very characteristic of painting. The central areas of the shell are of a yellowish ground, blotched and variegated with black. The terminal and lateral areas are very dark green, with the prominent granules con- spicuously tinged here and there with yellow. The ligament is strikingly tessellated with dark and pale sea-green. (/.
Korean Archijtehtgo, under stones (Belr: 9
130 I8CHN<>< IUTON.
coreanicus Ri:i:\ i. I'. X. S. 1847, p. 24; Conch. Icon., t. 26, f. 128.— AI.AM- iV Kvi :.. Voy, 'Samarang' Zool., Moll., t. 15, f. 9. — S< HIM N< K. llek u. I-'oi-M-l). ini Amur-Lande, ii, p. 281, f. 1-0. — Lophyrus c<> DKK., Ind. Moll. Mar. Jap., p. 1 ~>7.
Carpenter (MS.) compares this to /. pcctinulatus and 7. co«y Schrenck reports it from the Bay of Hakodadi, on the- authority of Lindholm. I. JMI.CHKKRIMUS Sowerby. PI. 27, figs. 47, 48.
Shell oval, elevated; jugum acute; mucro conspicuous, elevated, median. tlie slope behind it concave. Color red, variously clouded or streaked with ashy. Jugal area hardly defined, smooth at the prominent beaks ; central areas having 16 to 18 acute, subparallel lir;«' on each side, meeting over the jugum but otherwise nearly parallel ; interstices crenulated ; entire surface granulated. The interstices are decussated by the buttresses, as it were, of the cren- ulated sides. Lateral areas with 3 principal rows of close knobs, inrreasing to 5 rows by intercalation. End valves having 16 to 20 such rows, the interstices crenulated. Sutures with sharp rows of granules in addition to the contiguous ribs. Interior: anterior valve with 7, central 1, posterior valve 10 slits; teeth obtuse, striated, slightly pectinated ; eaves small ; sinus deep, flat, dentic- ulate. Girdle tessellated, imbricated with large, solid, more or less striated rounded scales. Divergence 97°-107.° (Q>r.)
Length 24, breadth 13 mill.
Island of Bo hoi, 7 Vi ///;>;//
Chiton j>nlc.herrimus SOWB., P. Z. S. 1841, p. 103. — Rr.i Conch. Icon., t. 20, f. 132.
This species, says Carpenter, is very close to /. merte»*ii. The striation of the scales is conspicuous in some specimens, on others scarcely seen, yet they all appear conspecific. The species is exactly intermediate between the two genera, Chiton and Ischnochiton, the teeth being scarcely pectinate enough for Chiton, and yet it has the balance of its characters. One specimen has very little light, clouded with dark; one almost entirely light, with one dark streak on both sides of the central areas; other specimens are inter- mediate. ( Cpr.)
I. CRATICULATUS Gould. Unfigured.
Mucro central, scarcely elevated; central areas having 18-22 bars; on the acute, much elevated jugum scarcely obsolete;
ISCIIN'M || I IMS.
interstice.- traDSVenely wrinkled. Lateral areas havini: d< elevated Lrraniferotis rihlets, 1 in ymni.Lr, * I" H> in adult individ anterior valve having about ~ti} .-uch riblet-. Int. i '-rior
valve bavin-: I 1 , central valves 1, anterior valve 1 0 slits ; teeth short, not very acute, outside and at tin- margins in (rout rugulose, almost pectinated in front. Kav«> -mall, obi < |Q| short,
narrow, slightly denticulate. ( lirdle irregularly, closely imbricated •with small, smooth, solid scales.
Length 1T>, breadth 1 -~> mill.; divergence 93°. (Cpr.) China Nn/x, orJii/xni (Stimpson, N. P. E. E. ; 1 specimen in Mus. Smithsonian.)
Chiton (Le]ttochito)i) craticiilatus GOULD, Proc. Bost. Soc. K. II. vii, p. 101, Dec. 1859; Otia Conch., p. 117. — Lepidopleurus cratic-
it tut u* (1I'R., MS.
Dr. Gould appears from his diagnosis to have had several species under his eye when he wrote the description of this species. From his calling it a Leptockiton, he might have looked at the minute, chaffy scales of Trachydermon asperior ; when he wrote of long striated scales, he was probably observing Ischnochiton bixculptus. Again when he noted the great variation of the ridges (from 4 to 8), he probably had under his eye both /. cultratus and the species above described. Of the four, the balance of characters inclines me to retain the name for the shell last mentioned, although only one - imen was returned of it, mixed with the other three. Outside, the species is recognized by the solid smooth scales, and details of sculpture; inside by the blunt, somewhat rugulose teeth, which < in part of the anterior valve) are almost pectinate. (Q;r.) I. CULTRATUS Carpenter, n. sp. Unfigured.
Shell similar to " L. craticulatus " ; mucro central, planate, but central areas having about 14 to 20 very acute, strongly developed subparallel lira?, becoming less acute, somewhat obsolete, on the dorsal ridge ; sutures elegantly pectinated, interstices cancellated with small wrinkles; lateral areas having 4 low, gninifurous liruhe, and a fifth line of granules at the sutures, the grains sparse, small, but strongly projecting. Posterior valve having about 18 similar liruhe, anterior valve 24. Interior: posterior valve having i), central valves 1, anterior valve 8 slits; teeth acute : eaves projecting : sinu> small, deep, sensibly laminated, smooth. (lirdlo regularly imbri- cated with flat, smooth scales. (Cpr.)
.Length 27, breadth 17 mill.
132 racHHOOHirov.
If'ilcud'idi. Jit/Kin > Stimpson, X. P. E. E. Smithsonian Mu-.. 1672.)
Chiton pult'herrimus (pars) GI.I>., J/\, not Sowr,. — Leptorhiton •nlatus G i.i>., //<//>\ ( )iia, p. 117. (Cpr.)
This species differs from /. pulcherrimus So werby in having five rows of extremely fine, distant, but strongly expressed granules, instead of three (rarely four) of very coarse ones. This lias the space between the very sharp, knife-like central ridges but faintly cancellated with rugose lines; while in pulcherrimus the cancella- tion is so strong as to make the ridges appear granular. But the principal distinction is that pulcherrimus has strong striie on the mantle-scales, while those of cultratus are smooth and larger in proportion. It has the same general aspect as /. craticul<ttu* ; but differs in having the central ridges further apart and sharper ; the side rows of points scarcely half as numerous, and the scales much larger and more regular. ( Cpr., MS.)
I. MUSCARIUS Reeve. PL 24, figs. 9, 10.
Shell oval, jugum rather sharp, mucro at the anterior third, rather raised, the slope behind it very concave. Color a peculiar ash, with irregular brown spots over the central areas, and brown crescentic lines over the lateral areas ; and valves with spots of dark shaded with light. The central areas have a conspicuous (juincuncial granulation. Lateral areas somewhat raised, with about 7 very indistinct small riblets, also quincuncially granulated, and having an appearance of being concentrically sculptured, caused by the color-markings. Interior: posterior valve having 12, central 1. anterior valve 12 slits; teeth very sharp; eaves moderate, not spongy. Girdle covered with imbricated, smooth, moderately large, stout oval scales.
Length 18*, breadth 11, divergence 119°. (Cpr. from type in
r, M.)
Maxatlan.
Chiton muscarius REEVE, Conch. Icon., t. 24, f. 164. — Lepido- pleurus muscarius CPR., MS., p. 120. — Lep'ulnp tennis f mm-m CPR., Ma/at, fatal., p. 196. — Ischnochitou maeondrta CPB., .!/>'.. p. 88.
Carpenter seems to have decided that the /,. mnrandrei of his Ma/atlan Catalogue was identical with Hoove's C. w/.-'m /•/'//.•*, although he remarks that he would not have known it from the
E8OHKOCHIT<
and description u'ivrii l»y Reeve. I. PUBIO Sowerhy.
Shell oval, smooth ; olivaceous, ornamented with nimu-roiiggreen dots; front and .-ide margins of the valves rugulose. Marginal ligament scaly. Length 12*, breadth 7' mill. (Sowb.) ,
Valparaiso, on Amphidrsma Bolldum, 30-50 fin*. ; sand bottom. Chiton /mtio S<>\\ KKI;Y, I*. /. S. 1832, p. 105.
I. DALMI Haddon. PL 25, fig. 1-10.
Shell evenly covered with closely set minute low tubercles, wliieh give it a granular appearance; with straight-sides meeting at an an^le of 110°. Anterior valve closely granular, with twenty-six short radial rows of tubercles, each row consisting of four or five tubercles, which diminish in size from the periphery towards the apex ; the posterior row is the broadest, and is partially bifid.
Intermediate valves. Central area: jugum coarsely granular; pleura with about 12 or 13 distinct horizontal ridges; lateral areas granular, with three main radiating rows of tubercles, the anterior and posterior often partially double. Posterior valve remarkably fiat, coarsely granular, with nineteen rows of three tubercles each, of which the outermost is the largest ; umbo scarcely, if at all, raised above thje surface; anterior border coarsely granular, with the granules passing into oblique ridges on the pleura.
Girdle medium breadth, upper surface with smooth imbricating scales in oblique rows, about seven or eight in a row, those nearest the shell being the smallest. Color greyish -white.
Length 11, breadth 6, height about 3 mill.
Gills extending to about three-quarters the length of the foot, diverging posteriorly and hidden by a slight swelling of the longitu- dinal band on the under surface of the girdle ; about twenty-one in number, largest about the fifth from the posterior end, and gradually diminishing in size anteriorly. (Haddon.)
Lat. 51° 27' 30" S, long. 74° 3' W., 400 fins, blue mud.
Lepidopleunu dallii HADDOX, Challenger Polyplac., p. I1', t. 1, f. (>, t. :), f. 6a-6i.
I have associated this species with the name of my friend Mr. \V.
II. Dall, of the Smithsonian Institution, Washington, ( - A (Haddon.)
134 I-< IIN«i HITON.
I. MCI i.osrs Carpenter, n. sp. Unfigured.
'•11 oval, little elevated, the jugum acute; mucro slightly elevated ; brown-olive, elegantly dotted and clouded with darker, and sometimes maculated with ashy or roseate. Central areas gran- ulated in a somewhat quincuncial manner, rather regular lines radiating from the jugum. Lateral areas scarcely elevated, having 3 to 5 scarcely projecting radiating wrinkles; end valves having 30 to 40 subobsolete radiating wrinkles, and granulated like the central areas. Interior: posterior valve having 11, central valves 1, ante- rior valve 11 slits; teeth acute; eaves large; sinus moderate, flat, smooth. Girdle variegated, regularly covered with solid, large, sub- rotund smooth scales.
Length 15, breadth 10 mill. ; divergence 110°. (Qor.)
St. Vincent, Cape Verde Is*
Curiously like /. comptus in color and sculpture, but that species has the scales extremely finely striated, the side areas a little more decided, the granulation less regular, the painting more sombre and the sutures tessellated. These minute differences, joined with the wide separation in locality, probably denote a different origin. (Cpr.)
The type is no. 88 of the Cumingian collection.
I. OHTUSUS Carpenter, n. sp. Unfigured.
Shell small, strongly elevated, oval, the jugum little acute; mucro median, conspicuous. Reddish-brown, variously maculated with paler. Central areas having about 10 subparallel deep sulci on each side, obsolete upon the jugum ; lateral areas with 3 to 4 radiating wrinkles, sometimes divaricating, the end valves having 20 to 40, here and there interrupted by wrinkles of growth. Interior: pos- terior valve having 8, central valves 1, anterior valve 9 slits; slits small, teeth very short and obtuse, sometimes rugulose or almost pectinated ; calloused inside ; eaves small ; sinus moderate, exrurvnl, smooth. Girdle furnished with very close, small, very solid, rounded, smooth scales.
Length 12$, width 7' mill.; divergence 85°. (Cpr.)
Portugal (Mus. Cum., no. 105.)
A remarkable shell, presenting some general resemblance to mertensii in the appearance <>f the valves. The girdle scales are as small as in Trachydermon, hut very solid. The specimen is much worn outside, which may account for the bluntness and callosity .if the teeth, (f/
[ft HHO mi
I. i i M i S)\\rrl»y. 11. 27, l'iLr. I t.
Shell oval, cariualed, smooth : hack elevated ; lateral area- i, spicnoiis. ( 'oh»r lawny hrown, ornamented with rounded hlue Spots. Mar-in minutely scaly. Length 1 .">, hrradth !> mill. (Sowb.)
"Newcastle, AvttraUa?
C. lentiginosus Sown., The Magazine of Natural History, con- ducted by Ed w. Charlesworth, iv, new series, p. 293, .June. 1840; Conch. Illustr., f. 120.
Chiton cyaneopundatus KRAUSS, Die Siidafric. Moll., p. 40.
Kxcept in heing somewhat larger, and said to be from a different locality, this seems to be absolutely the same as /. cyaneopnndatut Krauss. It is likely that the Australian habitat assigned to lenti- guiosus is a mistake. The description of cyaneopunctatus here follows :
C. cyaneopunctatus Krauss. (PL 27, figs. 40-43). Shell si.iall, oblong-ovate, thin, semi-pellucid, convex, carinated, shining, a.-hy, orange or brown, closely painted with dots and lines of blue ; very minutely punctulate; intermediate valves narrow, subrectangular ; lateral areas slightly distinct ; end valves delicately concentrically striolate. Girdle ashy and rufous banded, scaly, the scales distinct, subrotund, polished, shining.
Length 10*, breadth 6 mill, (jfifr.)
Cape of Good Hope.
The valves appear smooth to the naked eye, but under the lens delicate, elevated points are visible upon the central areas ; and on the slightly raised lateral areas and the end valves, there are very delicate concentric striaB. The head valve has 12, the posterior valve 13 slits. The median valves are very narrow (5'2 mill, wide, 1-2 long), with one slit in the insertion-plates. The scales of the girdle are as large as those of C. capensis Gray, shining, convex and rounded. The color is very various : gray, blue-gray, yellowish and reddish-yellow to brown shells occurring, but all show under a lens sky-blue dots, which frequently coalesce into lines. Tho girdle has darker transverse bands. (Krauss.}
I. DORSUOSUS Haddon. PI. 25, figs. 11-19.
Shell remarkably compressed laterally, the two sides meeting at an angle of 75°. Anterior valve concentrically ruirose, with about 26 radiating low irregular ridges, some of which hifuivate. < Vntral areas, with jugum and anterior border striated, the pleura will tinct horizontal ridges. Lateral areas distinct, concentrically rugose,
136 i-« IIN<>< •HITON*.
usually with three main radiating low ridges, the anterior and pos- r of which are often bifid. Posterior valve concentrically rugose, with fifteen irregularly arranged low radiating ridges. The anterior ridge is broader than the others, and may be slightly bifid, umbo rudimentary; anterior border smooth, with slight concentric lines of growth. Lamina- of insertion moderate in size.
Girdle narrow. Upper surface with ovoid, slightly overlapping, somewhat granular scales; edge with minute projecting spicules; under surface, with long, narrow, closely applied scales. Color white.
Length 21'5, breadth 7'f>, height 6 mill. (Haddon.')
Prince Edward's Island, Lat. 46° 41' S., long. 38° 10' W. 310 fros.
Lepidopleurut dorsuosus HADDON, Challenger Polyplac., p. 1 1 , f. 5 ; t. 3, f. 5o-5t. 1886.
Gills extending to more than half the length of the foot, twenty in number, the middle somewhat larger than the remainder. The name dorsuosus, full of ridges, is applicable to this species on account of its numerous longitudinal and radiating ridges, and at the same time recalling the steep ridge of the shell itself. (Haddon.)
I . \hii\ IDENSIS Reeve. PL 24, figs. 7, 8 (enlarged.)
Shell somewhat shortly ovate, very minutely reticulated through- out, under the lens; terminal valves and lateral areas of the rest finely ridged, ridges waved, central areas smooth, lateral areas not raised ; livid olive and yellow, flamed with brown in the middle, posterior edges of the valves articulated with brown ; ligament Lrnmately coriaceous, grains very large. (7?ve.)
I '<>rt Adelaide (Rve.) ; Port Molle, Queensland (Coppinger), Aus- tralia.
Chiton adelaidensis REEVE, Conch. Icon., 1. 19, f. 123. — C. (Isch- 'itonf) adelaidensis E. A. SMITH, Zool. II. M. S. 'Alert/ p. 79, 1884. — Lepidopleurus adelaidensis CPR., MS.
Smith L'ives the followini: notes on the specimens collected at Port Molle by Coppinger:
The entire surface of this species is minutely i:ranosely reticulated. the front valve, the lateral areas of the narrow central valves, and the hinder area of thepo.-terior are in addition somewhat irregularly radiately sulcate. The prevailing color is pale greenish, streaked and dotted with ivd, the posterior mar-in of the valves brinLT paler
BtHO HI i <
than the general tone of tin >hell, ami con-picuou-i;, \\itli
the same red color. The -ruins ..f the mantle an- .-m«n.tli. arranged in alternate grrrnisli and reddish patches, and individually have a
<lark spot generally on the outer side, which is only seen under a lens;
those near tho valves are considerably smaller than tho-e situated toward the edire of the girdle. Having parted the valves of or the specimens I find the front one has the innrL'in of iii.-.-rtion divided into seventeen unequal, Bquarely Out, slightly crinkled, -harp- edged teeth, of which the two outer on each side are the largest. The sixteen slits between the teeth are very small and shallow. The second, third, fourth, fifth, and sixth valves have on each side a single very small narrow central notch, from which a groove or depression runs to the apex of each valve ; the seventh is probably abnormal, having a single notch on the right side and two on the left, and the terminal valve has nineteen similar slits.
/. milleri (Gray) Reeve. (PI. 24, figs. 18, 19). Shell ovate, smooth ; central areas under the lens most minutely reticulated ; lateral areas very finely striated. Olive or sometimes white, blotched and dotted with black. Ligament coriaceous, tessellated with black and yellow. (Rve.*)
" Eastern Seas."
Chiton milleri ("Gray,") REEVE, Conch. Icon., t. 23, f. 156a ; t. 24, f. 1566, c.
This species was not described by Gray, although Reeve refers to the Spicilegia Zoologia. It has been stated by d'Orbigny to be a synonym of punrtnlatissimus. Carpenter seems to think it the same as adelaidensis. The types should be re-examined in order to settle the point.
I. SMARACil *ixrs Angas. 1*1. 00, fig. 20.
Shell oblong-elliptic, elevated, most minutely punctured, dull bluish-green, delicately freckled with olive, the hinder edges of the valves ornamented with very small white spots bordered with olive : the terminal valves and lateral areas faintly concentric-ally striated, the central valves carinated, with the dorsal areas faintly trans- versely striated, the lateral areas slightly elevated: the ma- margin pale green marbled with black, and covered with small smooth imbricated scale-. Length 1- mill. (Angas.}
Lilac, variegated with bluish, the >ide areas di-tinct, slightly raised, more variegated and darker than the central areas. ,Ji:
138 I8CHNOrmi<
sharp ; nmer<> not much raised, situated at the front fourth, posterior slope a little concave. Valves square, not beaked : Lrlo~\ -. \\ith very- fine quineuneial granulation. Inside : posterior valves having 10 or 11, central valves 1, anterior valves 11 slits; teeth sharp, thin, and rather Ion- : >inus broad, deep, flat, not channelled at the sides ; eaves projecting, granulated in quincunx but not spongy. Girdle with rather large, stout, smooth roundish scales. (Cpr., from types). Length 13 J, breadth 8 mill.; divergence iL'n .
Port Jackson, New South Wale*t Austral in.
Lophyru* *innr<i<t<li>ms AN<;AS, P. Z. S. 1867, p. 115, t, 13, f. 28; t. '•.. p. '2"2'2. — Lepidoplenrus smaragdinus CPR., MS.
I. SULCATUS Quoy & Gaimard. PI. 38, figs. 24, 25, 26.
Shell oval-oblong, quite convex, obtusely triangular, with narrow girdle ornamented with little, rounded scales, each of which is green. ish with a brown dot. The valves are wide, arcuate, almost without carina, very prettily grooved lengthwise on the sides, and zigzag in the middle. The lateral areas are triangular, granulose, and elevated. The anterior valve is simply granulated, with 11 or 12 teeth; the posterior valve is larger with 13 teeth, and above it is striated in front, and with marginal granulations. The sutural- plates are short and separated. All of these parts are of a hand- some clear green varied with white. The base of each of the lateral triangles is white. Each valve has at the summit a green spot surrounded with whitish, or sometimes with rose, in which case the interior also is roseate. Length 30, width 18 mill.
Port of Kiny Geor</e, S. Austral in.
C. sulcatus Q. & G. Voy. Astrol. iii, p. 385, t. 75. f. 31-36.— (Not Chiton (Jiadsia) sulcatus Wood.)
The generic position of this species cannot be known until the characters of the insertion-plates are more exactly described. The above description is from Quoy, who remarks that the species has considerable resemblance to C. viridis Q. & G. (G </»/o?// Dh.), differing in the sculpturing of the valves, especially the end valves.
I. TESSELI.A i r- nuoy & Gaimard. PL 24, figs. 13, 14, 15.
A small oval species, nearly flat, having a rounded carina. < .rav- ish all over, but under a lens showing white and brown elongated spots. The valves are very finely granulous, the lateral areas sulcated radially. The two end valves have smooth teeth. 12 in the head valve, and more on the last valve. The girdle is si-aly.
in i..\ i: \ i. -ii 1.1 \.
yellowish or greenish, and regularly .-potted \\itii i.n,\\n. ;
is narrow, yellowish ; tin- «;ills almo.-t reach the head. Length 1*. breadth 1'J, alt. 1 mill.
I'nrt ( '•//•/'•;•/•/, A'<
Chiton teasel In ht.< ({. & (J., Y«»v. <!<• PAstrol., Xooi. iii, j,. atlas, t. 75, f. 48-47.
The description is troin that of Quoy and Gaimard. The coloi is probably less vivid than shown in their phite. The artist of tin- 'Astrolabe' seems to have had an irrepressible fondness for green.
I. ARBUTUM Reeve. PI. 24, figs. 16, 17.
Shell ovate, terminal valves and lateral areas of the rest retieulatt-1 \ decussated with grained striae diverging off posteriorly ; central areas very closely sculptured with blunt squarish granules; green or red- dish, dotted with black; ligament squamately coriaceous, tessellated. (Jfoe.)
1'ort h**tn<:
. C. arbutum Rv., Conch. Icon., t. 24, f. 162.
Carpenter thinks this is probably a color variety of/, adelaidensia^ He gives the following notes on the 8 specimens in the Cuming collection: Shell ovate, tolerably elevated, rather broad ; ju<ru m more or less obtuse. Reddish orange, olivaceous or light ash, more or less spotted and clouded, but always with a very fine tessellation of dark and light along the sutures. Mucro in front of the middle, the slope behind it concave ; intermediate valves oblong, not beaked ; central areas coarsely and very regularly quincuncially granulated with large grains ; lateral areas very slightly raised, with about ^ rows of larger grains. End valves with similar grains, which are radiating but scarcely in lines. Interior: anterior valve havin-
II, central valves 1, posterior valve 16 slits: teeth quit typically Ischnoid ; eaves large, not spongy. Girdle tesst Hand with olive and light, covered with imbricating short roundish and quite smooth scales. Length 12^, breadth 8 mill.
Section Radsiella Pilsbry, 1892.
Radsiella PILS., Manual of Conch. (I) xiv, p. ~A .Inly i»5, 1892). Type, /. tridentatm Pils.— Jschnoradsia^Miri^i i :i: MS. and DAI i . Proc. U. S. Nat. Mus. 1878, p. 331. Not M//o/-,/,/.</./ SHOT n .\\.. 185,3.
Valves and girdle entirely similar to those of the mu-ma!
1 4< I ISCHNOCHITON-RADSIELL A .
chiton*, hut insertion-plates of the intermediate valves having twoor several slits.
The present section differs from Ischnoradaia Shuttleworth (Lep- idora<l*in ( 'pr.j, in having the girdle covered with flat, striated scales, whilst in the latter group the scales are transformed into smooth, solid, pebble-like bodies. Radsiella differs from the Radsioid section /v/f/xw in having the short contour and anterior mucro of the true Ischnoehitons, and in the normal foot and gills.
Carpenter's use of the name Ischnoradsia Shutthv. for this group is clearly indefensible, as Shuttleworth mentions none of the > now included herein, whilst his diagnosis covers all Radsioid forms of Iscknochiton. I have therefore restricted the namelschno- r>i'l*ia to the forms grouping around Shuttleworth's first species, auttralis.
I. TKIDKNTATUS Pilsbry, n. sp. PL 18, figs. 35, 36, 37, 38, 39.
Shell small, oval, moderately arched, slate-color with white spots and dots, or white mottled with slate ; the girdle tessellated with alternate dark and light, the interior blue, with a leaden spot under each BUtural-plate, and short dark rays from the apex.
The valves are evenly arched. The posterior valve (fig. 39) has a central, rather depressed umbo, the slope behind it concave. Lateral areas raised a trifle, but scarcely distinguishable; central areas evenly, closely and finely pitted in quincuncial pattern ; the lateral areas are a little more coarsely sculptured with close low diamond-shaped granules ; the granulation generally less regularly arranged on the end valves than on the lateral areas.
Interior with low, arched sutural-plates and wide, flat, angular sinus; anterior valve with 13, posterior 12, central valves 2 slits. Teeth sharp, smooth. Eaves very narrow.
Girdle covered with imbricating striated scales (fig. 36.)
Length 15, breadth 10 mill.
l.aTnz, Lower California (Lockington) ; Gulf of California (Gab!..;
/ • M ,/•'/</, -l,t d ispar C A i : i • i : N r i : K, ^fS. n ot Sow i : i : i : v . This species is easily separated from I. dispar Sowh. by the apparently similar sculpture of central and lateral arras, the sculpt- ure in iH*intr being obviously diverse on these areas. I suppose this to be what Carpenter considered ih'.tpar merely because it has valves : but Carpenter has given no description of his shells.
l-< IINoi III |..\ l; \ |. -| 1. 1. 1, A. 1 II
Tin- l'"«t i- not produced forward l>ni<';ith tin- h< ad, a- i: Stenoradria, The irills extend from tlic front end of tl within somewhat less than tin- width of a valv from tin- t.iil • -,
I. vii:ii.ri.r> Couthouy. 1M. 17
Shell small, ohloiiLr, rather elevated and dc«-id»-dlv «;irinated; creamy yellow, or "of a very pale olive or drab color." Surface smooth to tlio naked eye, but under a lens it is seen to be every- where covered with low granules quincuncially arranged, lateral areas are a trifle raised, but not distinctly so, and upon them the granulation is somewhat effaced, and a few very obsolete radiat- ing sulci are generally distinguishable, as well as several rather strongly indicated growth-periods. "Interior: posterior valve hav- ing 13-14, (rarely 17), anterior valve 14-16, central valve?- slits. Teeth acute, distant; eaves acute, projecting, hardly spot sinus wide, short, flat. Girdle covered with rather large, wide scales, deeply and distantly striated." Length 13, breadth 7 mill.
Orange Harbor, Terra del Fuego.
Ch. viriduhis COUTH. MS., GOULD, Proc. Bost. Soc, N. H. ii, p. 144, 1846; Otia Conch., p. 5 ; U. S. Expl. Exped., Moll., p. 318; atlas, f. 413. — Ischnoradsia viridulas CPU., MS. — Lepidopleurus viri- dulus KOCHEBR., Miss. Cape Horn, Polyplacophores, p. 140. — 'f Minochiton viriduhis Gld., HADDON, Challenger Rep., p. 16,1886.
A small form, evenly granulated, and having indistinct lateral areas. I have taken the description of the internal parts from Carpenter's MS., as I have not examined the interior of the single specimen before me, which is one of the original lot.
I. TRIFIDUS Carpenter. PI. 18, fig. 40.
Shell rather large, rather elevated, regularly oval ; red-ehotnut. maculated with lighter and darker; jugum acute, gothic. Mucro median, flat; entire surface very minutely granulated ; central areas having about 8 strongly punctate lines perpendicular to the jugum ; lateral areas strongly defined, having 2 to 4 obsolete ribs, sonutim.- punctate in the interstices.
Interior whitish flesh-colored, with two reddish-purple rays diverg- ing from the flat umbones ; posterior valve havin_r !•'>, anterior central valves 2 slits; teeth acute, sometimes serrated at the edge, sometimes striated outside, sometimes smooth. Kaves subspongy ; sinus small, laminate, the lamina slit at the sides and sometimes in
14'J ISCIIN.X mi'.N IIAI.HI.I.I.A.
the middle. <;irdlc having very small, solid, >mooth scales. Gills almost ambient. ( < 'pr.)
Lenirth 40, breadth i>ii mill.: divergence 135°.
Sitka to Pug^t Sound, 9-18 fms.
Tr.H'hwI.nnn,, tni',,ln.« OR., Suppl. Kep. B. A. 1863, p. l>4'.» ; Proc. Acad. Nat. Sci. Phila. 1865, p. 60. — Ischnoradsia trifida CPR., .!/>.. and PXI.I., I'roc. U. S. Nat. Mus. 1878, p. 881.
I have not seen this species. The figure is from a rude sketch in Carpenter's MS. Dr. Dall writes of it as follows:
This rare and fine species is not particularly handsome, being of dull and livid colors, but is peculiarly characterized by the straight transverse ribs on the dorsal areas with spongy interspaces, and by the pretty regular division of the lateral areas into three well marked radiating costa?, which are separated in the insertion plate by two fissures. No other species of the region resembles this in srulptuiv. Mu/x.le with a pectinated margin in front produced into rounded lappets at the corners. Gill rows as long as the foot, con- taining each 28-35 branchiae. Veil absent. Mantle edge plain, narrow. There is a small spherical lump on each side of the girdle just behind the posterior ends of the gill-rows, which are turned out toward the girdle and widely separated behind. The anus is large median, and crenate, opening on the upper part of the hinder end of the foot. No ovarian openings could be detected, and the species presents some peculiarities which call for further research with more material. (Dall.)
1. KKCJULARIS Carpenter. PL 18, figs. 41-46.
Shell oblong, elevated, dorsally carinated, the side slopes straight. Surface appearing almost smooth to the naked eye. Color a uni- form olive or slaty-blue, the girdle having more or less of a blue or purple " bloom."
The lateral areas are very little raised, and are sculptured with numerous delicate radiating threads, occasionally branching toward the lower margin, and freely branching along the posterior edge of the valve. The terminal valves have similar delicate radii. The central areas have numerous longitudinal, somewhat beaded threads, separated by flat intervals. The posterior valve is elevated, with anterior uml»o.
The interior is light blue. Sutural plates low, connected across the HMIIS by a narrow plate which is silicate above and cut into
in i"N i: \ Den 1 1 \.
;ihi>ut 10 trrth liy delirat" .-lit-. Anterinr v:il\«- : • Tin nil '2 •"., poMrrior •_'•_' -lit.-. Terth even MIL! -harp, -li. -triatrd or grooved outside. Kav.- solid, (lirdle uid« , • eivd with solid, regularly and closely imlmeat iiiLr -triuted Scales 16), Len-th 85, lueadth, 1H mill.
Monterey, ( c/iifnn regulari* CPB^ P. /. B, 1855, p. 'i'.vi.--l.--'>.l,<.,,,(bia
r I- y n/> m'.* CPB., J/N.
This species is of a very regular form, and a uniform dral>, -dive or blue color. It is not closely allied to any other West Coast form. Tlui number of slits in the posterior valve is unusually large.
I. TIGRINUS Krauss. PI. 19, figs. 60-63.
Shell oblong, convex, roundly arched, buff-white, unicolored, or striped lengthwise with reddish ; rarely roseate.
Valves without apices. The lateral areas do not extend to the middle of the back; they are raised, and cut into radiating riblets by 8 or 10 narrow impressed grooves, and there are rather con- spicuous concentric wrinkles or waves of growth on the lower part of the areas. The end valves are similarly sculptured. Central areas closely and regularly pitted all over. Posterior valve rather large and depressed, with subcentral urn bo.
Interior white and light brown. Anterior valve having 17-18, central valves 2-3, posterior valve 12-13 slits; teeth rather thin, but somewhat bevelled and roughened inside; eaves solid. Sinus wide and flat, the sutural-plates being rounded. Muscle-scars dis- tinctly impressed.
Girdle rather wide, firm, densely clothed with somewhat coir finely striated scales (fig. 63). Length 22-28 mill.
Cape of Good Hope.
Chiton tiyrinus KRAU&S, Die Siidafric. Moll., p. 38, ? Ischnoradsia subcariosa CPR., MS.
This species is readily known by its Radsioid valvi- and tln> beautiful web-like sculpture of the central areas, produced by the pattern of regularly arranged rhombic pits. It is like no other species, although the young of /. magdaleneiisis bears a slight resemblance in the sculpturing of the central areas.
Although technically a Radxiella or Stenor' is not easy to
decide which) this species probably was developed from a different stock of Ischnochitons. Indeed, the multiplication of side-slits may
1 1 I [SCHNOCHTTON-IBCHNORADeiA,
,i'ccted to occur in any branch of Chitons; from the genus IschnochUon alone, we have at least tour or five independent Kad-ioid branches.
The typical /. tiyrinm* of Krauss is >triped longitudinally. The unstripnl form, of which several specimens are before me, may be called var. nnicolor.
The species mentioned by Carpenter as /. subcariosa may be a form of /. tiijruina. The type is a single specimen of unknown origin, and is in the museum of McGill College, Montreal.
Subgenus VII. ISCHNORADSIA Shuttleworth, 1853.
Ischnoradsia SHUTTLW., Berner Mittheil. 1853, p. 65, species cited C. australix and C. magdalenensis. Not Ischnoradsia CPR. — Lepido- radsia CARPENTER, MS.; and DALL, Proc. U. 8. Nat. Mus. 1 p. 33 1 , type C. australis.
Valves having sharp but rather thick insertion plates, those of the median valves with two or several slits. Girdle covered with convex, pebble-like, smooth scales. Type Chiton australi* Sowb.
The typical forms of this section are from the Australian seas, but several species have also been found in Japanese waters.
Carpenter's substitution of the name ' Lepidoradsia ' in place of Ischnoradsia, was in direct violation of the rules of nomenclature.
Key to species.
a. Sinus dentate within, albrerhti.
ad. Sinus smooth.
b. Central areas longitudinally ribbed, australi*,lHt/ubrw. bb. Central areas minutely granulated.
c. Outside green, inside green and pink ; scales very convex,
novcehol/andke. cc. No green or pink ; scales small, convex, lutkodadensis.
I. AUSTRALIS Sowerby. PL 18, figs. 57, 58, 59.
Shell oval-oblong, moderately elevated, the dorsal ridge sub- angular, side-slopes nearly straight. Color dark olive-brown, the apices of the valves pink when eroded.
Lateral areas somewhat raised and sculptured with close, unevt n riblets, which usually bifurcate or branch freely, especially toward the posterior maririn of the area. Crntrdl ureas closely and eienly
rSCHNCX HITOB fSCHlfOB LDtt \.
?/•//// y/'/irr /nni/ifinlinu/ r/A/r/x, ;>}>-<. Ictc »n t! win -iv they _irivc place to a d»-n.-r microscopic Lrran illation. apices of the valvc^ arc pink in mature >he!U. Knd valves sculpt- ured with clo>r radiating ril.lets, those of the posterior valve irreg- ularly ^ranose; IIUHTO rather depres.-ed ; posterior slopes of th- valve depressed and concave.
Interior liirht blue-green, with two wide pink rays in each v and behind them two olive-brown rays. Sntural plates nun whitish or yellowish; sinus wide, flat, not in the least toothed. Insertion plates having 16-21 slits in the anterior, 2 or 3 in the median, and 17-21 in the posterior valve; teeth rather thick and stumpy, and a, little rugose, but sharp edged. Eaves wide and solid. Girdle (fig. 57) wide, closely covered with conspicuous, convex, pebble-like scales, which toward the outer edge are subcatinated in the middle.
Length 62, breadth 35 mill.
Port Jackson, Australia.
Chiton australis SOWERBY, Mag. of Nat. Hist. (Charlesworth's), June, 1840, p. 290 ; Conch. Icon., f.46. — REEVE, Conch. Icon., t. 2, f. lO.—Lophyrus australis ANGAS, P. Z. S. 1867, p. 221.— Lepido- radsia australis CPR., MS. and DALL, Proc. U. S. Nat. Mus. 1878, p. 279, t. 2, f. 19 (dentition) ; p. 333 (branchia>).— HADDON, ' Challenger ' Rep., Polyplac., p. 1 9. — Chiton (Ischnoradsia) australis SHUTTLW., Bern. Mittheil., 1853, p. 66. — C. evanidus SOWERBY, Mag. Nat. Hist, iv, June, 1840, p. 291 ; Conch. Illustr., f. 139.— C. metallicus RVE., Conch. Icon., t. 17, f. 104, 1847.
This species is distinguished from the following by the fine longitu- dinal ribbing of the central areas. The synonymy given above is unquestionable.
Occasionally one or more of the teeth is cloven into a number of small ones ; the number of teeth varies considerable.
Dall found the gill rows to extend the whole length of the foot, and to contain forty-seven branchiae in each. Mantle-edge plain, thin ; muzzle plain, semicircular, without a veil.
I. NOV.EHOLLANDI.E (Gray) Reeve. PI. 19, figs. 67, 68, 69.
Shell oval-oblong, elevated, the dorsal ridge an.Lrul:< opes
nearly straight. Color green, minutely marbled with olive, the lateral areas darker. 10
14''. GBCHNO< in i' H iRADBIA,
•••r;il areas somewhat raised, sculptured with low, uneven, some- what nod ulous radiating riblets, and some concentric growth-wrinkles. • ireas smooth o-<r/>f /o?* a very dense and reijnhtr microscopic fjrnniilnti<ni. Knd valves having radiating rihlets; mucro rather prominently raised ; posterior slope concave. Interior blue-green, with pink and olive rays. Sutural plates rounded; sinus smooth, not toothed. Anterior valve having about 19, central valve- posterior valve 1* slits. Teeth thick but sharp ; eaves wide, solid.
< iirdle covered with smooth, solid, pebble-like scales, which toward the outer edge, are subcarinated. Length 43, breadth 23 mill.
Adelaide, S. Australia.
Horn hollnidicc (GRAY, MSS. in Brit. Mus.) REEVE, Conch. Icon., t. 21, f. 142, May, 1847.
This species has much the appearance of I. australi*, but it differs totally in the sculpture of the central areas, and somewhat in that of the lateral areas. The girdle is just like that of australia, except that the pebbly scales are smaller in a specimen of the same size. Carpenter erroneously considered this species a synonym of Chiton '' U<i<l$ia) goodalli.
I. LUGUBRIS Gould. Unfigured.
Shell small, solid, punctate, elongate-ovate, slightly carinated, emerald-green. Central areas sculptured with longitudinal line, smooth at the apices. Lateral areas elevated, having branching nodulous line. Knd valves radiated at the margins, umbo sub- central. Girdle wide, covered with large transverse convex scales. (.Old.}
Interior : end valves having 19-24, central valves 2-4 deep slits; teeth acute, sometimes a little rugose at the margins ; eaves very short, spongy ; sinus broad, flat, smooth. Girdle imbricated with very solid narrow, nearly smooth scales. (Cpr.)
Length 25, breadth 15 mill. (Old.)
Habitat unknown,
Chiton (Lojthyrus^) luyubris GOULD, Proc. Bost. Soe. Nat. Hist. vii, p. 1 »'>-">, Dec., 1859; Otia Conch., p. 116. — Lepidoradiia lugubri*
GUI.. < I'.:.
The girdle, says Carpenter, is very like that of 7. <insfr<ilit, from which the strong sculpture distinguishes this species.
181 UN'" iinoN m HHO1 \i»HIA. 1 J7
I. ii LKODADI ran ( topenter, D, >p. 1M. in. ligs.fji. *'<~>t 66. Shell oval-tihloiig. moderately elevated, l>ack railn i mindly arched,
<c:mvly keeled. Soiled hull', maculated an«; •.-. iih Uarki-h-
brown.
Lateral areas slight! j raised, cut \\\\<> <! to 9 low flat un»''|ual
rihlets by radiating impressed lines, the rihlets made IMU-VI n \>\ cent rie wrinkles of growth ; central areas very mi nutcly pitted all over, the surface being something between aquinemirial granulation, and a succession of ww-like zigzags. End valves having fine radiat- ing riblets cut by some cencentric growth-sulci. Mucro in front of the middle, rather prominent.
Interior blue-white ; sinus smooth ; sutural plates low, rounded ; anterior valve having 15-20, central valves 2-3, posterior valve 15 narrow slits ; teeth rather sharp, sometimes slightly roughened ; eaves short, narrow, solid.
Girdle covered with small, solid, convex, smooth scales (fig. 66).
Length 25, breadth 15 mill.
Hakodadi, J
This species, which was collected by Wm. Stimpson of the North Pacific Exploring Expedition, has very much the aspect of /. / co*us Old. of Australia, the sculpture of the central areas being of the same zigzag character. From all species of the /. longi- cymba group, however, this is distinguished by its smooth, convex girdle scales, and by the plurality of slits in the side insertion-plates. The above description and figures are drawn from part of the original specimens.
I. ALBRECHTI Schrenck. PL 19, figs. 70-74.
Shell large, oval, elevated, the dorsal ridge acute ; mucro median, nearly flat. Reddish maculated with darker, the interior having rays of reddish-brown.
Entire surface minutely and closely punctate; central areas with about 30 lines of granules oil each side of, and parallel with, the jugum ; lateral areas having in the young 4 to 6, in the adult 10 to 12 radiating, distantly granose riblets; the end valves having 50 riblets.
Interior: posterior valve having 12, central valves ? to 3, ante- rior valve about 17 slits ; teeth acute, sometimes rugose or lobed at the edges, outside ; sinn< moderate, 8 to 12 dentate.
148 OHirOKD
Girdle pretty regularly covered with large narrow, -olid, smooth scales. ( '
Length 40, breadth 25 mill., divergence 112°.
Hakodadi, Japan.
Chiton albrechtii SCHRENCK, Bull. Acad. Imp. Sci. de St. Pelersb., v, p. 511 ; Reisen u. Forsch. im Amur-Lande, ii, Zool., p. 283, t. 13, t'. 7-17. — Chiton (Lepidopleurus) albrechti E. A. SMITH, Ann. & Mag. Nat. Hist., (4), xvi, p. 115, 1875. — Lepidoradsia granofilosus CPR., J/N.
The form collected by H. C. St. John, R. N. at Endermo Harbor, Japan, is larger, (length 65, breadth of central valves 28 mill.), the lirations on the lateral areas are not granulated, and all the valves are distantly concentrically sulcated.
Subfamily CHITONIN^E.
Lophyroidea CpR.,-\-Acanthoidea lophyroidea and Acanthoidea
typica CPR., table of Regular Chitons, 1873, and in Dall, Proc. U.
at. Mus. 1881, p. 284 (1882).— Chitonidce and Acanthopleuridcs
(part) DALL, Catal. Marine Moll. Southeast Coast, Bull. 37, U. S.
Nat. Mus., p. 172 (1889.)
Regular Chitons having the insertion-plates well-developed on all of the valves, and closely grooved or pectinated outside and at edge.
The retention of Carpenter's groups Lophyroidea and Acanthoidea in anything like the limits given by their author, is simply impos- sible. On the other hand, a perfectly natural group is obtained by uniting these two groups, after excluding the "Acanthoidea isch- noidea" Cpr., and the group Craspedochiton Shutt., which have special characters not yet noticed in print.
Within the group thus constituted, four genera having well- defined characters are distinguishable, all of them agreeing in the pectinated insertion-plates, though varying in the degree of pectina- tion.
Synopsis of Genera.
A. No eyes developed on the valves, a. Girdle scaly.
Genus XII. CHITON Linn.'.
Valves having one or several side-slits in each insert ion-plate, and a deticulated sinus separating the sutural plates ; girdle scaly, the
( III
mi. 1.^1 ami s.»li.l, closely imliriral in-, rarely separated. Type ••n/ntiix Limn'.
mt. ( iinllr willi <lnu-t Kristles.
mis XIII. KUDO \OCHITON8huttleworth.
Valves having several side-slits in each insertion-plate, the suturul-plates continuous across the sinus, which is represented by a mere wave; girdle leathery, heset with short, stiff bristles. Type C.
no In /is Gray.
AA. Eyes developed on end valves and lateral areas, a. Girdle leathery, nude or nearly so.
Genus XIV. TONICIA Gray.
Valves having pectinated insertion-plates ; sutu nil-plates separated by a squared denticulate sinus; eyes developed in more or less regular rays on forward part of lateral areas and on end valves. Girdle leathery, naked or with a few hairs. Type C. elegans Frembly.
aa. Girdle covered with spines or spinelets.
Genus XV. ACANTHOPLEURA Guilding.
Valves having pectinated insertion-plates with one or several side- slits, the teeth in the posterior valve directed/orward instead of out- ward ; sinus denticulate or smooth ; eyes small, scattered among the granules of the surface. Girdle bearing long calcareous spines, or closely clothed with short ones. Type C. spinosns Brug.
Genus CHITON Liiiirf, 1758.
Chiton L. Syst. Nat. edit, x, p. 667 (first recognizable species C. tuberculatus*) ; edit, xii, p. 1006. — SPENGLER Skrivin- at' Naturhist. Selsk., 1797 (first species C. tubermlnlH*}. — LAM.M:< K, I'rodr. Anim. s. Vert., p. 90, 1799 (sole example fit <s). —
WOOD, Gen. Conch, and Index Test. (C tuberculatus the first species). — GUILDING, Zool. Journ. v, p. 27, (example, C. sqnamonu &OVfB.=tuberrulatu#).—l rBAY, I'. /. S. 1 - >, 06.— Sun i
Bern. Mittheil. iv, p. 72. — CARPIOM 1:1: A- D.M.I.. IV . I'. S. Nat Mus. i, p. 300 (1878), type C. tnbercuhttus.— Not Chit,,,, II. ^ A. AD., Gen. Rec. Moll, i, p. 474 (1858.)
Lophyru* (in part) POLI, Test. utr.Sicil. i, mnltn-ntri'i, p. 2, 4, etc. — H. A A. ADAMS, Gen. K«r. Moll, i, p. 46!> -in part.)
150 < HI TON.
'lopleurus (in part) Risso, Hist. Nat. Kur. M.'rid., p. 267.
Oymnoplax GRAY, in The London Medical Repository, Monthly Journal and Review, xv, p. 234 (Jan .-June, 1*21.)
Valves wholly external, the beak of the tail valve median or anterior; insertion-plates longer than the eaves, slit into teeth which are deeply and finely pectinated, and typically project outward on all the valves. Girdle covered with closely imbricating, convex, smooth or striated scales. Gills extending the entire length of the foot.
Hi.<toni "f ti'iincs for Chiton. In the tenth edition of his Systema Naturae, Linne includes in the genus Chiton the following species: hi" nidus, (" C. testa sexvalvi striata. Habitat . . "), tubercnlatn.«, •itus and jtiun-ttttns. Of these the first, hispidus, is now univer- sal lv admitted to be unidentifiable, as no information or reference further than that quoted above is given. The next species is a well- known West Indian form, and has been cited as the first species or tvpc of the genus by Spengler, Guilding, Gray, and nearly all authors. Li line's third species, aculeatus, is apparently unidentifi- able, but probably belongs to the genus Acanthopleura ; the fourth, pnn'-fiitns, is if possible less recognizable ; and even its modern genus cannot be determined. The name Lophyrus Poli has been used for the group by Messrs. Adams, but it can have no standing on account of the fact that Poli proposed that name for the soft parts only, retaining the name Chiton for the shells, in accordance with his curiou.- ~y-tem of double naming. Poli's first species of Lophyrus is L. melph'i hidi is the soft part of Chiton cinereus L. ! Only
one of Poll's four species belongs to the restricted genus Chiton. The history of the name Lepidoplenrns is given on page 2 of this volume. The history of. the name (V///////o//Au- is as folh>\\
•ay. in his article "A Natural Arrangement of the Mollusca according to their internal Structure" (Med. Repos.), under the h«-ad of •' Or<l. 1<> /V*///A/ro/;//o/v/," enumerates the synonyms of that term, defines the order, and otters the following arrangement: i'lates placed on the hack of the mantle.
1. < iymnoplax or jrymnoplacidae. Acanthochitona. Chiton facirularis. Ix'ptochitona. Chiton marginatus.
/'. Plates sunken in the hack of manlle.
2. Cryptoplax. Chiton larv:eforinis."
The inference from this would 1 e that Gray intended to include in " < ivmnoplax or irymnoplacida- " all Chit ms having exposed
• Illl I .") 1
val\-e>. a meaning also favored by the etymology ; but in I'. /
\^\^ he places (iiiiiiiinfi/ii.!- under <"/,//,, a synonym. In
anv ca>e, tin- name (//////;/»•///'/./• cannot I" V<T heen
diaLrM«>sed except in the uvneral way <|iioted above, and no-pecics lias ever hecn rxpivss ly deH-naled a< hrlnn^Ji,^ to it. The name has been ii>«'il by <iray only in the instances above mentioned and \va-. MS \ve have seen, considered a synonym hy him in his later writings; hut it should he noted that the invpre.Vihle Kochehrune, still Uflefl <;:n,iintjt/»i.r in a generic sense, in order presnmahly, to disguise his species; — an unnecessary precaution, for his diagnoses of Chitons generally defy indeiktificatioD of either genus or species.
In conclusion : it is obvious that the name Chiton must be retained for a group typified by one of Linnets original species ; and since the tubereulatus is the only one of the original li.-t which has been or can be identified, that species becomes the type of the genus. No other position on this question is reasonable or tenable.
The most natural primary division of Chiton is into two groups; one to include all American and some Old World species, in which the mucro is anterior and the scales smooth, the other to include Old World species having the mucro subcentral and the scales striated. As this division is based upon characters not always easy to see, the following division into sections is more convenient.
Section CHITON (restricted.)
Median valves having a single slit in each insertion-plate; sinus generally denticulate ; scales closely imbricating.
Section RADSIA Gray.
Median valves having two or more slits in each insertion-plate. Section SCLEROCHITON Cpr.
Median valves having a single slit in each insertion-plate ; teeth of tail-valve tending forward; sinus smooth; scales of girdle separated.
Section CHITON s. str.
Artificial key to specie* of Chiton.
A. LATERAL AREAS RADIALLY SCULPT i KI:I>.
a. Central areas having longitudinal riblets.
b. Sides and ridge of central areas both sculptured.
> < m r<>.\.
c. Urabo of tail valve distinctly in front of the middle. d. Ril>let> of lateral areas rather smooth and fine. e. Dotted or spotted with Mm-. /. Large, black, dote Bmall,
ff. Small: dots large, ee. Concentrically Hneated with brown or dark, cumhufi. eee. Unicolored or blotched.
/. 17 slits in head and tail valves together, perviridis.
ff. 22-24 slits in head and tail valves together, quoyi.
fff. 35 slits in head and tail valves together, subfuscus.
ffff. 30 slits in head and tail valves together, bowenii.
dd. Riblets of lateral areas granulose, irregular, or much
forking.
e. Lateral areas with 3-4 rows of pustules, granosus.
ee. Lateral areas with forking or meshing riblets.
/. Riblets 8-10, fine ; slits in head and tail valves together about 40, i-iri/ulatus.
ff. Riblets coar&er, netted ; slits fewer, stokesii.
Umbo of tail valve about central. d. Mucro depressed, slope behind it hardly concave,
pellisserpentis.
dd. Slope behind mucro very concave, burmmttin.
bb. Central areas with a smooth band or triangular on ridge of each valve. Murro in front of the middle.
i-entral areas curved or converging,
e. Lateral areas sparsely pustulose-lirate, viridis.
ee. Lateral areas with interrupted or netted lira-.
tubereulattu,
</</. Riblets of central areas parallel or diverging forward. e. Lateral areas and end valves pustulose, granosus.
ee. Lateral areas and end valves granose-ribbed,
ofmaKeulatut.
eee. Lateral areas 1 irate, nigrovircns, perviridis, densi I trains. Muero about ••entral. d. Lateral areas with low. smooth riblets, olh"irc us, (jereus,
affin I*.
dd. Lateral areas with feebly ^ranox- ril.l«-t>, tusul'ir!*.
ddd. Lateral areas with Lrrano>«- or noilo.-e ribs.
•. Lateral areas with o-l, pleura '2~> riblets, <Ki€
• III i
ee. I.ateml MT6M uith L' :!. pleuni 1 1 rihl«-K
aa. < entral :uv:is .-moot!). lacking longitudinal ril
b. Fnd valves un-aiio.-r-lirale or pu-tuloae.
C. Fnmt ot'di:i;r<m:il line obviously wrinkled or j»itti-«l. d. Shell and girdle uniform dark LI ru«/
•itl. Shell variegated, gird! -mated, afotrt.
'/(A/. Shell or irinllr vnii'-l. BOalei smooth, viY/'
l-'roiit of (liiiLronal line smootli.
il. I'ustulcs .-<';itifi-nl : >iiril and girdle UDiform blackUb,
mar '/(/. Finely Ix-adcd ; ihell and girdle banded, .^/////?no«««.
66. End valves finely striated.
C. Shell oblon.ir. divergence about 110°.
Shell elongated : divt-rp-m''' about 98°. f><»<
AA. LATERAL AREAS SMOOTH OR CONCI:VI 1:1- M .1 .v w n.i'irRED.
a. Whole surface smooth. b. Mucro near the anterior margin.
c. Color black and olive-yellow, with snowy lines, (ilhu/in- cc. Purple or olive mottled.
d. Sutural-plates within dark-blotched at base; sinus nar- row, ''j'ttiift.
d<L Suttiral-plates within not blotched; sinus wide,
marmoroto*.
bb. Mucro central, tidipa.
aa. Central areas longitudinally sculptured, (species not tabulated.)
West Indian species.
Mainly large forms, with smooth scales and notably anterior mucro. They are closely allied to the species of the Panamic region.
C. TUBERCULATU8 Linne. PI. :53, figs. 58, 59, 60.
Shell oval-oblong, rather elevated, carinated, thoide-slope- nearly straight. Color varying from light olive to dark Driven <>r dark olive-brown, unicolored sometimes, but generally speckled on the side-areas and end-valves, often clouded on tin- central an of the valves having a dark stripe on the ridge.
Lateral areas raised, sculptured with about -\eord-like radiatm- riblets, which are sometimes subcontinuous, but usually are much
154 « IIITON.
interrupted :in<l broken, and bearini: :i few low tubercles. Central areas smooth along the ridge, the sides sculptured with longitudinal riblets curving inward, becoming coarser outwardly and diverging. End valves closely tuberculate all over, the pattern resembling that <•!' an ciiLrine-turned watch case. Umbo of tail valve near the front margin.
Interior blue-green, very smooth, the snttiral plates lighter: sinus narrow, toothed. Anterior valve having 13, central valves 1, pos- terior valve 14 slits; teeth blunt, pectinated. Slit-rays hardly ornot
Girdle white, buffer light green, alternating with patches of dark green or blackish. Scales rather coarse, convex, polished. Length 60, breadth 33 mill, (average Jamaica specimen.) Length 90, breadth 55 mill, (specimen from Nassau, N. P.)
Bermuda, Florida and Texas to Trinklul.
Chiton tuberculatus LINNE, Syst. Nat. x, 'p. 667 (1758). — HANLEY, Shells of Linn., p. 12. — Chiton squamosus BORN, Test. Mus. COBS. Vindob., p. 5, t. 1, f. 1. — CHEMX., Conchyl. Cab. viii, f. 788-790.— REEVE, Conch. Icon., t. 3, f. 16.— HADDOX, Chall. Polyplac., p. 20, and of all modern authors. NOT Chiton sqmnnosus Linne. — Chiton undatus SPENGLER, Skrivter af Naturhist. Selska- bet iv, p. 68 (1797).— C. bistriatus WOOD, Gen. Conch., p. 7 (1815). — / C. tessellatm WOOD, 1. c., p. 23.
This species has been generally considered to be the squamosus of Linnreus, but that the Linnsean name belongs to another species must be regarded as established. The references quoted by Linna-us in the tenth edition of [the Systema clearly show that this is the species which he culled tuberculatus. In the twelfth edition other references not applicable to the species are added ; and the figures given by Chemnitz, Horn, and others under the incorrect name "squamosus" have caused subsequent authors to adopt the latter nan
This species is the commonest Chiton of the W--i Indies, and is readily known by its (typically) strong, curved ribs and peculiar sculpture upon the end-valves, which Reeve aptly compares to that of A lathe-turned watch case. It is extremely difficult to draw a line between this species and ( '. n^lmi/i^ of Keeve; so difficult, in fa< -l, that I have be«-n unable to satisfactorily distribute a portion of the specimens In i'.n me between the t\\... Linna us describes tu-
• Ill
bereulatus MS nfrt'ii-rii/i'fil ; and oddly enough, mie of 1 In- • collected l.y I >r. II. Sharp at Toba-" i- aUo apparently .-«-v.-n-\ alved,
having two of the valvei linnly loldered lit of an
early injury. It is likely that the B6VOT and -ix-valved ( 'hit-. us :ihed by early author.- were partly abnormal specimen- of tins c'haraeter. and the rest \v iv (minded upon careless and MOO]
Bgur
Color-var. Color a uniform dull blackish ; rihlets of the central area- finer and coim-r^ini: near to the median line. Area behind the sinus in-ide, and the slit-rays solid, not spongy or pon.u-.
nuda.
I have 8681) a -reat number of specimens, but mostly BO <-roded that the permanence of the characters could not be decided.
Yar. ASSIMILIS Reeve. PI. 33, figs. 61, 62.
Fawn colored, with white dots on the lateral areas, the ctirina handed with brown ; girdle light green. Central areas «mtj>tured with very fine, close riblets. Interior having the >lit-rays and the area behind the sinus porous.
St. Thomas to Barbados.
Chiton f/.Wm/7/x KI:I:VK, Conch. Icon., t. 14, f. 76 (right hand figure) ; f. 77b. (March, 1847.)
Color-var. ater. (pi. 33, fig. 63). Shell having the close fine sculpture of assimilis, but black in color, dark green-blue inside.
St. Kitts (Rush) ; Tr'>ni<L,<l (Sharp.)
C. SQUAMOSUS Linne. PI. 85, figs. 80, 81, 82.
Shell oblong, elevated or rather depressed, carinated, the side- slopes somewhat convex. Surface of lateral areas minutely headed- central areas smooth ; lusterless. Color butt' (pale or deep in t the central areas regularly and oonspicuotuly striped longitudinally with gray or black, most valves having a wider dark blotch on each side of the keel, and a series of spots along the back edge.
The lateral areas and en<\ vtlues are raised n/i<! sculptured trith radiating rows of fine beads, the number of rows increasing by inter- polation ; and under a lens the surface is seen to be ininntt'lij j>uitct>tte. Cf-nfrn/ urcua not sculptured, save for inconspicuous growth-lines. MIKTO of posterior valve near the front margin.
Interior dark blue-green, the sutunil plates lighter. Sinus rudely denticulate. Anterior valve having 12, central valvt > 1. p >-terior
!•"•»'> < IIITON.
valve l:J slits. Kavos narrow, .-hort. somewhat spongy; sinus and slit-rays hardly porous. Teeth pectinated.
Girdle alternately light green and whitish, covered with smooth convex-flattened scales.
Length 60, breadth .".2 mill.
Len-tli 4:», breadth 28 mill.
Cuba, Jamaica, St. Thomas and St. Croix, West Indies.
Chiton squamoms LINNE, Mus. Ulricae, p. 465 (1764). — Chiton niosus L., Syst. Nat. xii, p. 1107. — SpENGLEBSkrivter at' Natur- historie-Selskabet iv, p. 67, t. 6, f. 2 (1797).— HANLEY, Shells of LiniKeus, p. 15 (1855). NOT C/iiton squamosus of authors. — Chiton BPENGLEB, ]. >•.. p. 68 (a depressed form; see Chemn. viii, f. 792, 793). — Chiton scaber variegatus CHEMN. Abh., p. 31, t. 1, f. 3 ; Conchyl. Cab. viii, p. 276, t. 94, f. 792, 793.— Chitonfasciatus WOOD, Gen. Conch.. IS]."), p. 10, t. 1, f. 4, 5 (excl. syn.). — SOWB., Conch. Illii.-tr.. f. 1 .y;.— SHUTTLW., Bern. Mittheil. 1853, p. 74.— Chiton cheinnit-ii PKR., Krit. Register zu Mart. u. Chemu., p. 78, 1840. — Chiton marmorem REEVE, Conch. Icon., t. 12, f. 64 (not of Chemn. nor Fabr.)
This species is colored in much the same fashion as some striped forms of C. marmoratus, and it also agrees with that species in the smooth central areas; but the dullness of the surface and the minutely beaded lateral areas at once separate the two forms. Specimens vary greatly in degree of elevation and consequently in the size of the angle of divergence.
LiniKeiis gives an unusually full description of this species, amply sufficient to distinguish it from the shell which Born, Gmelin, and later authors confused with it. Spengler correctly identified it in his monograph of 17'.»7, and gave a most excellent figure and a good ription. Hunley found Linnaeus' original type still preserved in hi- eollertion, but the C. squamosus of authors is not present there. It should hi- noted that Linnaeus' specific names of Chitons were intended to In- descriptive of the girdle*, not the valves.
rjUDIfl Spengler. PI. 33, figs. 64, (if), (Hi, 67. Shell oval, moderately elevated, carinated, side-slopes slightly con- vex. Color varying from gray-white to olive, irregularly marked
on tin- central area- ..r on the rid«jo with blackish : some! lines hlack- hrnwn all o\
(ii i I..N. 157
Lateral ATOM strongly raised, :iml wulpturtd »•//// •
low r'nli'itint/ rih.t Item-ing nf irrcgn/ur or regular inh-rrn/.-- rnumh'd j. I tin ,-<iili'<iti><g /'/'Ax, tli.- i> ,r ///,,/
rior lionlrr of eacb valv gen< nil;.
ticulated. OwUro/ oraoi tmoo^i hi the >/m/<//v, but tm^pfurtfd <i/<tng
///»• tlingmi'il linen with <t ncrien <>( nlmrt rilm f»'tit in ///»• .<//'////• o/' //
reversed s Mud valves l)c;irinLr radiating series oft aber-
cles, or with only a lr\\ scattered tiil)«'i-clcs. Murro uc:ir the front
margin.
Interior light b/nc or light green. Sutural |ilat«-s lii:lit«T, highly arclu-d, tlie sinus deep, narrow, angular, the straight dentic- ulate portion from •] to i the length of a sutural-platc. Anterior valve having 13, central valves 1, posterior valve 12 slits.
Girdle alternately whitish and brown or green, finely scaly.
Length 36, breadth 22 mill.
St. Thomas ami M. < ',•<>!.,• (Swift) ; Jamaica.
Chiton *(]n<nnosus denticularis, etc., ('HUM MI/, Conchy 1. Cab. x, p. 372, t. 173, f. 1689.— Chiton viridis SIM:N«,LI:I:, s'krivu-r af Naturhistorie-Selskabet. iv, p. 70, t. 6, f. 5 (1797). — WOOD, General Conch., p. 15 (1815). — CAifam /oveo/atu* SOWERBY, Charles- worth's Mag. of Nat. Hist. 1840, p. 290; Conch. Illustr., f. 60.— Ki:i:\ i:, (Jonch. Icon. t. 6, f. 28. — Chiton costatus C. B. AD., Proc. Bost. Soc. Nat. Hist. 1845, p. 8. — Chiton (Lophyru*) gemmnlatus SHUTTLEWORTH, Bern. Mittheil. 1853, p. 75.
Doubtful references: — Chiton squamosus, testa septen-valvi-striata, etc., CHEMNITZ, /. c. x, p. 374, t. 173, f. 1690,= F<m'etef af Chiton undatus, SPENGLER, Skrivter af Naturhistorie-Selskabet, iv, p. 69 (1797). — Chiton tessellatus WOOD, Gen. Conch., p. 23 (1815).— Chiton excavatus (Gray) SOWB., Conch. 111., f. 131 (never de- scribed.)
This species is well distinguished by the series of short CM i wrinkles along the diagonal latero-posterior edges of the other smooth central areas, and by the sutural denticulation, when this is developed, which is by no means always the case. The diagnostic features of the species are stated with great clearness by the Danish naturalist Spengler, and also by Chemnit/, but the figures given by them are poor. There is great variation in the development of the pustules upon the lateral areas and end valves.
158 < IIITON.
M:MORATUS Gmelin. PI. 34, figs. 72, 73, 74, 7~>, 70.
Shell oval, rather elevated, the dorsal ridge varying from roundly- angular to distinctly carinated; side-slopes convex or straight. Sur- face smooth, polished. Color varying from olive to dark brown or purple-brown, variously marked with darker spots or blotches and liirht longitudinal stripes or lines.
The lateral area- arc a little raised ; the whole surface showing a very minute quincuncial pattern of granulation under the lens, and marked with inconspicuous growth-lines. Mucro close to the front edge of the tail-valve, as in C. Icevigatus.
Interior blue-green, each valve often having darker or olive pos- terior rays. Sinus deep, angular, having a jagged convex row of denticles, half as long as a sutural-plate. Anterior valve having 11- 14, mitral valves 1, posterior valve 13-17 slits; teeth deeply finely pectinated. Eaves, slit-rays and triangle behind the jugal sinus very porous.
Girdle alternately blotched with green and light blue.
Length 56, breadth 32 mill.
Length 48, breadth 26 mill.
Texas (Dall) ; Bermuda (Heilprin) ; Jamaica (Cpr.) ; Cuba ; St. Thomas (Swift) ; St. Croix; St. Vincent (Sharp) ; Barbados (Rush) ; Carthagena, U. S. Columbia (Krebs.)
Chiton marmoratus GMEL., Syst. Nat. xiii, p. 3205.— (Chiton marmoreus CHEMNITZ, Conchyl. Cab. viii, p. 282, t. 95, f. 803-805. Not C. marmoreus REEVE). — C. marmoratus Sows., Conch. Illustr., f. 148-150.— REEVE, Conch. Icon., f. 6.— SHUTTLW., Bern. Mittheil. 1853, p. 74.— DALL, Cat. Moll. S.-E. U. S., p. 172.— C. scarabceus REEVE, Conch. Icon., t. 12, f. 66.
This species is excessively variable, but with all its variety I have seen no specimens having the pattern of the West Mexican C. l&vigatus and articnltifns. The following color-patterns are commonly met:
1. Entire surface of valves blackish-brown. This is not an uncommon form, being the C. scarabcRus of Reeve.
2. Olive, with fine flecks and lines of whitish, becoming confluent toward the middle.
3. Either purple-brown or olive, having longitudinal zebra-like stripes on the side-slopes.
CHITON,
This -pi-firs is amply dislin.Lrni.-hed from 1'. /nrlf/'ifn.-- hv tin- wider sinus, dillrtvnt Ooloriagj and l>y tlir iniirli more porous lines |f iiiLT toward llir .-Ills, and (lir eon>piriiou>ly pomii- triaiiL'l' under tin- dorsal ridi:r of each valve, as shown in li:
Species of the West coast of the Americas.
This is a natural jrroup of lar.Lre species, character i/fd bv the generally somber color, large smooth scales, and anterior nuiero. l!<td.*!'t is a tangent from this circle of speei
C. LJEVIGATUS Sowerby. PL 34, figs. 68, 69, 70, 71.
Shell oval, subdepressed or elevated, carinated, the side-slopes somewhat convex. Surface smooth. Colors soft and blended, ing from purple-gray to olive, lighter in the middle, where there are three irregular longitudinal series of black or dark blotches ; back edge of each valve often articulated with light and dark spots.
The lateral areas are a little raised ; whole surface polished, show- ing a microscopic quincuucial granulation under the lens. Mucro unusually close to the front edge of the tail valve, almost marginal.
Interior dark green-blue ; the sutural plates lighter but having a large dark green or blackish blotch at the base of each. Sinus deep, si jiiare, with a convex row of jagged teeth. Anterior valve having 17, central valves 1, posterior valve 21 narrow slits; teeth blunt, deeply laciniate ; eaves short, narrow, spongy.
Girdle wide, tessellated with alternate light and dark.
Length 55, breadth 38 mill.
Length 85, breadth 55 mill.
Gulf of California to Afif
Chiton lavigatus Sown., P. Z. S. 1832, p. ~M ; Conch. Illustr., f. 18*. — REEVE, Conch. Icon., t. 7, f. 35. — Chiton artictthttiis Sowi:i:i:y. P. Z. S. 1832, p. 59; Conch. Illustr., f. 18.— Ki i h. Icon.,
t. 2, f. 7.
Sowerby's description of Icevigatus precedes that of »//7/V;/A////x in the P. Z. S., and since the two forms prove to belong to one species, the former name must be accepted. Fig. 69 represents the
There is considerable variation in the decree of elevation and in the contour, but the extremes seem to be connected most intimately by specimens intermediate in form. This species has a general
160 < HITON.
resemblance to the West Indian smooth Chiton, (\ but it differs in the plan of coloring both inside and out, the West Indian species lacking the dark blotches upon the bases of the sutural-plates, which are so characteristic of Icevigatus. The marmoratus, morever, has a proportionately wider sinus, the straight toothed space between the sutural-plates being half as long as each plate, whilst in Icevigatus it is only one-third as long. This last character, together with the internal coloring, will always distinguish the two species.
C. ALBOLINEATUS Sowerby. PL 32, fig. 57.
Shell oblong, parallel-sided, moderately elevated, carinated, smooth ; lateral areas, end valves and dorsal keel black, marked with -•i-nile radiating lines. Sides of the central areas light olive- green, some of the valves occasionally black.
The lateral areas are a little raised; entire surface most minutely granulated in the usual quincuncial pattern. Beak of posterior valve anterior.
Interior light blue, the sutural plates paler. Anterior valve having 15-16, central valves 1, posterior valve 16-17 narrow slits ; teeth strongly pectinated. Eaves narrow, short, spongy. Sinus denticulate.
< iirdle firm, blue-gray, compactly covered with convex-flattened polished imbricating scales.
Length 35, breadth 18 mill.
Todos Santos Bay, L. California (R. E. C. Stearns) ; Mazatlan (Cpr.) ; Acapulco (Ruschenberger.)
C. albolineatus SOWB., Zool. Journ. iv, p. 368 ; in Zool. Beechey's Voy., p. 149, t. 40, f. 4 ; Conch. 111., f. 39.— C albUineatns Ri Conch. Icon., t. 2, f. 11. — Lophyrus albolineatus CPR., Maz. Cat., p. 191.
The apparently smooth surface and the conspicuous snowy stripes render this a very distinct specific type. Each scale of the girdle when examined under a lens is seen to be of a delicate blue-green color, edged broadly with white.
C. MAONIFICUS Deshayes. PL 30, figs. 23, 24.
Shell large, oval, moderately elevated or somewhat depressed, the dorsal ridge indistinctly carinatrd. -id. --lopes a little convex. Color Murk, H'itli minute blue dots scattered rather thickly over the valves; girdle bla<-k.
.in 1 1 ; I
Tin- lateral . \ n-\ lilt !<• rai-ed, and sculpt im-il wit li a
10 small suholxoletc radiating rililets : central area- «•!«.. -«-ly and linely sculptured with longitudinal nUeis separated l.y «!• interstice-. I'.^terior valve having tin- limbo near tin- front DUU tlie slope behind it straight.
Interior light l)lue; sutural plates wide; sinu- square, finely toothed. Anterior valve bavin-' '•> 1-, cent ral valve- 1. post valve I'J 11 slits; teeth stout, blunt, deeply pectinated. Kave- sliort and narro\v, spun.
(iirdle - lig. -\ > strong, covered with .shining, convex, imbricating
seal
Lentil) '.)•">, breadth 60 mill.; divergence 120°.
Valparaiso, C '// /'//'.
Chiton mitgnijicus I)n., Diet. Class, des Sc. Nat. xii, p. 4-V> : I-jicycl. ^Feth., p. 680; Lam., An. s. Vert., ed. Dh., vii, p. 498.— J{I-:I-:VK, Conch. Icon., t. 1, f. 3. — Chiton latus SOWERBY, Catal. Sh. Tankerv., appendix, p. v, (not Ch. latus Lowe). — Chiton olivaceus FREMIM.Y. Zool. Journ. iii, p. 199, Suppl. pi. 16, f. 4. — Cliiton nfrlnhi* UAUNKS, Amer. Journ. of Science vii, p. 70, t. 3,f. l.(1824). Not ('. ttriiifns of authors.
This large olive-black, blue-dotted species is remarkable for the evenness and smoothness of its sculpture. It is an unusuallv hand- some Chiton.
C. MURRAYI Haddon. PI. 29, figs. 15-21.
Shell apparently smooth, but really very closely and finely striated, the striae being roughened or interrupted ; greatly depre
Anterior valve with radial stria-; under surface with eleven dis- tinct square slits, radial grooves distinct and perforated; teeth of insertion plate serrate. Intermediate valves narrow, tlatt. non-carinate, with sharp depres.»ed umbo, surface stria? longitudinal in central areas, radial in the lateral areas; lateral areas distinct, with slight-concentric ruga-, and with three or four >carcely apparent peripheral radial ridges, which die away toward the apex ; sutural laminae shallow, a single lateral slit, lateral insertion plates Ben juguni with nine rounded teeth, the central beiinr verv small. Pos- terior valve flattened, slightly umhonatc, stria- longitudinal on the anterior area, radial on the posterior an -a : under surface with seventeen distinct slits, teeth serrate : jugum finely toothed. 11
• II! I
Color, upper surface ground color of shell a greenish- -rhtly
clouded with dark brown and black ; umbones lighter ; on eacl of the latter the ground is yellowish: whole, wrimr «],ritik!fd with pale blue spots, which are bounded externally by a black line; on ••i-ntral areas, the spots run in irregular, oblique, hackwardly diverging lines, and have a slight tendency to confluence, but on the lateral areas and terminal valves the spots are irregularly scattered; under surface, pale sea-green, darker along the jugum, and with a dark spot at the umbones of the terminal valves.
Girdle: upper surface with large imbricate scales, of which the exposed portion is smooth, the hidden portion being usually finely striated longitudinally ; color, dark green, with a tendency to form darker bands opposite the valves; in the angles between the valves a few of the scales are paler and yellowish in color; under surface with long narrow oblong white scales arranged in transverse series.
< Jills extending along the whole length of thefoot, about fifty- live <>r >ixty in number.
Length 12'5, breadth 7%3 mill.
The following Chitons also have blue spots: Chiton magnificus Desh. and Chiton dvrjuncttu Fremb. The latter is also from Valparaiso, but it would be impossible to mistake these for Chiton murrnij'i. Superficially, this species bears some resemblance to loplcurut lentiginosus Sow. (G. B. Sowerby, 1840, Charles- worih's X. S. London's Man. Xat. Hist., and Conch. Illust., 1841, figs. 120, 121 ; Reeve, Conch. Icon., 1847, pi. xxiv, fig. 165,= Chiton letatu* KKAUSS, Die siidat'rikanischen Moll., 1848, pi. iii, tiir. -) ; but apart from the generic distinction, Suwerhy's species can be distinguished by the perfectly smooth shell, inconspicuous lateral an as. paler color of the shell generally, and absence of the external black border to the blue spots. I have given myself t Ill- pleasure of dedicating this pretty and distinctive little Chiton to Mr. John Murray of the Challenger Expedition. (Haddon.')
Valparaiso, Chili on the shore.
Chi \\ . Challenger Polyplac., p. 1>1, t. 1, f. 7;
t. 3, f. la-le.
•
C. 8UBFU8CU8 Sowerby. PI. 38, figs. 19, 20, 21, 22.
Shell < h-vated, carinated, the sidr-slopes nearly
straight. Surface rather shining. Color dark olivi-hrown. or olive-
raved will) brick-red, (or " copperat-jpreen or reddish, i
ss tlamed \villi jet-l>lael
Tin- lateral -in. -\\hai '. itli
11 inn ' - " , ii'/ti'-lt «
rnpted by grow th-lines. Central I dptim-d \,\
irniwth-wrinkles. and by //m' /»n</iti<(li>i<il flirentlx. ir/n'r/i nrr, <;• nil]! ol>*«/rtr "i- ,ilw)it or/-/*/ mi f/inj;-nnt of //<>- dnrnnl r'i<\<ji> of Wive, Kml valves having radii like tin- l:it«-r:il areas, their uneven- ness iriviiiL: the valve a superficially pitted or tinely netted apt anee. l>eak of tail valve near the anterior margin.
Intoriur pale l)Ini>h, the sutural-plates whiter. Anterior valve having 15, central 1, postrrim- valve 20 slits; teeth rather sharp- I, strongly crennlated inside and out; sinus-area spongy ; slits ami slit-rays coarsely sponiry. Kaves short.
Girdle densely covered with fine, smooth, convex, shining, black or olive-black scale-.
Length 4'J, width '24 mill.; divergence 110°.
Island of Chiloe (Cuming) ; Chili.
Chiton *nhi'n.<cn.-< SOWERBY, P. Z. S. 1832, p. 26.— CA/Vo// .<triatus Bttrnw, Si.wi;., Com-hol. Illustr., f. 3, 41 (excl. synoii. i. — ('. l!i:r.vi:. Conch. Icon., t. 1, f. 36. Not Chitim *triutu.<
This species is closely allied to C. mmjnifn'U8j but differs in being smaller, narrower and more elevated, in lacking l)lue dots, and in the partial obsolescence of the longitudinal striation of the central areas. Figure 19 represents the form which judging by his measure- ments Sowerby considered typical. He aftewanl united o//V A////.N- and atr'nilii* (all of which=mo^nt/S(n« Dh.) with .<?»//>/'/ Reeve adopted the name .s/r/'"/'/.«, and figured the shell repi-e-eiited by Sowerby's fig. 3 of the " Conchological Illustrations." This is copied in our fig. 20. We are constrained by thetermc l»y's
original description to adopt the folio wir nt.
Typical tnlniscus Sowb. PI. 38, fig. 19.
I'alt; ashy olivaceous green, streaked and mottled with black : imdinal seulpture all over the mitral areas, and radiating sculpture on lateral area.-, both .-tr": loped, the latter a little
interrupted into regulations.
The relations of this form with m<nji> ;ire inv« -
164 < I II TON.
Y;,r. mesoghjjitns Pilshry. PL 38, figs. 20, 21, 22.
Olive-brown or brown, unicolored or rayed with brick or blood- t he latter sometimes predominating. Central areas having a group of longitudinal striae on the dorsal ridge, but smooth or nearly so on the pleura. Smaller than the preceding.
I have seen a considerable number of this form, which is the " var." described by Sowerby and figured in Conch. Illustr., fig. 41. I am unable to say whether it intergrades with the true subfuscusor not.
C. BOWENII King. PL 38, fig. 23.
Shell large, elongated, elevated, the dorsal ridge car in ated; red- dish-chestnut, olive, or ashen streaked with olive. Mucro in front of the middle, the slope behind it straight.
Central areas smooth, sometimes with delicate longitudinal strise at the ridge ; lateral areas elevated, delicately radiately striated, the end valves similarly sculptured. The entire surface is microscopic- ally granulated in quincunx pattern.
ln>ide having 13 slits in the anterior, 1 in the central, 17 in the posterior valve; teeth pectinated, eaves small; sinus wide, flat, with 12-16 teeth.
Girdle olive-brown, in all the varieties of valve-coloring ; scales solid, rounded, regularly imbricating, and small for the size of the shell.
Length 82, width 38 mill. ; divergence 98°.
Length 68, width 32 mill.
Strut ft of Magellan.
Chiton bowenii KING, Zoolog. Journ. v, p. 338 (1831 or 1832).— SOWERBY, Conch. Illustr., f. 37. — REEVE, Conch., Icon., t. 2, f. 9. — SMITH, P. Z. S. 1881, p. 35. — ROCHEBRUNE & MAT.II.U:. Moll. Cap Horn, p. 141.
Distinguished by its comparative smoothness, unusually elongated form, and highly ridged back.
C. CUMINGI Frembly. PL 30, figs. 29, 30, 31.
Shell oval or oblong, elevated, the dorsal ridge angular, side- slopes nearly straight. Whitish or olive, very closely and regularly d with brown or lead-colored lines which are concentric on the end valves and lateral areas and converge forward on the central. areas; often blotched on some or all of the valves with lead-brown or buff.
( III 1
Tin1 lateral an. parated from the central area- l»v an
oblique curved ridge, hut scarcely raised; sculptured with*; or 7
low radiating riblets, somewhat dedicated by longitudinal sub- ol)st>lete riblets. The central aiva< are sculptim-d with Longitudinal rildets liner than those of the lateral areas. End valve.- having radiating riblets and less distinct concentric lira-, the iimbo of po.— terinr valve near the front margin.
Interior pale bine ; sinus flat, toothed; anterior valve having 10, central valves 1, posterior valve l.'J slit>; teeth blunt, pectinated.
Girdle clothed with smooth, convex, imbricating scales.
Length 53, breadth 34 mill.
Length 56, breadth 31 mill.
Valparaiso, Chili.
C. cumuiynii. FRKMI'.I.Y, Zool. Journ. iii, p. 198, suppl. pi. 16, f. 3. — C. cwningsi DH. in Link., An. s. Vert, vii, p. 500. — C. cumin '/ii, SOWB., Conciiol. Illust., f. 32.— REEVE, Conch. Icon., t. 1, f. 2.
This well-known species is of a bronze-olive color, closely lineated with brown or olive. The lines are not distinctly -enough shown in the figures. The range of variation in contour and color-pattern is considerable. It has been reported from the Cape Verde Is. (Nouv. Arch, du Mus. 1881, p. 282), but there cannot be much doubt that the citation is based on a false locality label.
C. STOKESII Broderip. PI. 30, figs. 25, 26 ; pi. 32, figs. 50-53.
Shell oval, moderately elevated or depressed, the back cariuated, side-slopes straight. Brownish-black, toward the middle often more or less marbled longitudinally with dirty white.
Lateral areas somewhat raised, closely sculptured with radiating, irregularly gntnnlous and anastomosing riblets. Central areas sculptured throughout with low close longitudinal riblets, often made slightly granose by the lines of growth. End valves covered with a net-work of nodose riblets generally very much interrupted ; umbo of posterior valve near the front margin.
Inside smooth, varying from blue-white to light blue, the sutural plates paler, all of the valves marked with a spot of dull brown. Sinus deep, rather narrow and angular, jaggedly toothed. Anterior valve havinir 1<>, Central valves 1. posterior valve 15-16 slits.
166 ( HITON.
( .irdle (pi. 32, figs. 53) covered with solid, convex, subcarinated imbricating scales. Length 68, breadth f>0 mill.
Gun?/ . II >>•> Mexico, to Panama and West Coliunhin.
Chiton stokesii BROD., P. Z. S., 1832, p. 25.— S,,\vi;.. Conch.
mufltr., f. 24.— REEVE, Conch. Icon., 1. 1, f. 4.— M..I:< H. Mai. 151.
vjj p 171; — Chiiun jtnttilu* Sown., Charleswortli's MULT. Nat. Ili.-t.
. p. •_".»! : Conch. Illustr.,f. 134.— RKKVE, Conch. Icon., f. 30.—
>il,fn.< CPU., J/\
The sculpture of the lateral areas is peculiar, being something like the meshes of a stretched net, but the cords or riblets are irregularly irranulose. In uniting the C. patulus of Sowb. to stokesii, I quite agree with Carpenter, who writes as follows: The form patulus is typically " engine-turned " on the terminal valves, with strong ruga? on the sides, and larger scales on the girdle. A young specimen sent by Mr. Cuming has only 18 slits in the tail plate. The typical stokesii has the terminal rugae radiating, and sometimes a row of color tints at the sutures. The bulk of the Panama and San Juan i niens (of which I have examined many hundreds) are so variously intermediate between the two forms that I find it impos- sible to separate them even as varieties. The scales are extremely deciduous, and specimens in good condition are not often found. It was often the custom of Mr. Cuming to select extreme forms for his cabinet; and these being described and figured as the normal types of species are very apt to mislead students who work by single specimens.
( '. vi 1:1.1 i. \ rrs Sowerby. PI. 32, figs. 54, 55, 56.
Shell ohlonir, parallel-sided, rather elevated, the dorsal ridire ear- inated, side-slopes straight. Lateral areas and end valves olive- brown, or like the central area< which are green, longitudinally cl..iided with blackish : girdle jinn ami W/W. t ransversely or longitu- dinally banded.
The lateral areas are raised and -culptur.-d with rwmenut s-10)
ifiti'i rifift.'t-*, irli ic/i /mi' "-// //, sji/it or branch. Central
areas sculptured with longitudinal rihlets which at the sides diverge
a little and are nearly as coarse as those of the lateral areas, hut
finer and parallel to the rid^e toward the middle. Km!
valves having dose radiating riblct> : ap. \ of tail valve ante) i
In-ide dark I>1> sutural-plates hi'jh. blue-irr- en. Sinus
angular and tootln-d. Ant-.i-r valvi- liavinjr '1\-1'1, <-cnh*<il
• ill ION.
posterior valve I !i 20 " i'' • th \vid»-,
blunt, pectinated ; bort, narrow. BpODj
( ;irdle compact!;, I with solid, */*//////;/ convex scales (pi,
82, li.ir. ••
ofena /.' ft/omw ; ';>///'"/ Calij
- WB. in Charlesworth's Mag. Nat Hi>t. 1840, P. L'!»I ; Conch. Illustr.. 1'. 132.- REEVE, Conch. Icon., t. 21, f. 140.
Thi> species is allied to ('. N/fi/w//, hut differs in bring narrower, more elevated, dilierently colored, in having the riblets iim-r. inoj-e nunuM-oiis and less anastomosing, in the color of the interior and in the iinmher <>f .-lius which is much Lfi'eater in the end valves of this species than in those of C. ttnketii, and in some of the intermediate valves there are two slits in one or both sides. The entire surface, as usual in this genus, is microscopically granulated. The girdle- scales are liner and smoother than in <". s/o/r*//, and the sutural- plates are different in form.
A square mm. of the girdle is shown by the dotted line in fiir. ~><>.
It has been reported from Australia, but erroneously. Many spec- imens are before me from the localities given above.
The remarkable feature of this species is that it forms a perfect transition between the restricted genus Chiton and the section /iV/>/</. Some specimens have two slits in one end of one valve only; others have two slits in the majority of the valves; and scarcely two are alike in the arrangement of 1-and 2-slit insertion- plates. I have examined the interior in about a dozen individuals and have always found at least one insertion-plate Radsioid, but probably a larger series would reveal specimens with the normal plates of ( 'lit t<> a >•. x.
C. GRAN08U8 Frembly. PI. 30, figs. 27, 28.
Shell oval-oblong, moderately elevated, scarcely earinated, the side-slop«-> somewhat convex. Black, having a white stripe <»t e<icl>
i the central l'm<\ clouded with whitish between the .-tripes. Lateral areas bearing three or/'"/.-- "'</</-///•< on a
ih ground: <•,•////••// iirea* hnrintj a narrow smooth dorsal bandt the sides (pleura) covered "•/'/// dose, fine longitudinal -.vhidi
are more or less crenulated by the gn»\\ th-lines. Knd valves hav- ing rounded pustules in radiating rows or irreguhirlv scattered; umbo of tail valve near the front margin.
CHITON.
Interior whitish clouded with olive-plumbeous posteriorly and on autural-laminse ; sutaral-platee wide, sinus rounded, toothed:
lor valve having 14-1."), central valve- 1 , pi.-tennr valve 15-18 slits; teeth hlnnt, pectinated: eaves short, .-pongy. The sutural lami: .o »th in-ide. the anterior-median fni'-t is finely wrinkled
nor tract is punctate.
tiirdle clothed with coarse, angularly-convex, imbricating scales. Length Id, breadth 2i; mill.
'//'//'<;/' /Vm/'/-<, r«t<nj<>n'nt ; V<i/jKir<u#'>, ('hill.
1'liiton fjrano*n* FKKMKLY, Zool. Journ. iii, p. 200, suppl. pi. 17. f. 1 (1827). — Dn. in Link., An. s. Vert, iii, p. 500. — SOWB., Conch. Illustr., p. 2: Moll. iBeechey's Voyage of If. M. S. 'Blossom,' t. 4<>. f. .">. — IIi:i-:vi:, Conch. Icon., t. 5, f. 27. — LojJii/rti* (j,-an».-«i* TAP. < IAN. Viag. ' Magenta' p. 75.
The pustulose lateral areas and end valves and the black, two-
striped color-pattern are the stronger features of the exterior of this-
nid the interior is no less strongly marked by the trans-
wrinkling of the front part of each valve, which may be readily
seen under the lens without dis-articulating the shell. This wrink-
ling in other species is confined to a band the width of the sinus, and
is much le.-s strongly developed. The second valve is broad and
beaked, with only a narrow smooth dorsal line : the following valves
have a distinct smooth band.
( . 8TR1 vn N9QUAMO8U8 ( 'arpenter.
Shell s'ibrotund, depressed, pale brown-olive ; entire suriace of the
valves densely granulated : lateral areas rather distinct, valves wide,
.-liirhtly curved, scarcely beaked; jugum scarcely distinct, very
delicately longitudinally striated, lateral margins planate : mucro
iior. -lightly distinct.
Girdle furnished with solid, oval, large hardly crowded scale-, part deeply siriated : maririns <>f t he valves serrated ; median valves with a .-ingle .-lit on each side, end valves having about 12 slits: .-iitnral-plate- i '".-ly arcuate.
Length } . l.r.-adth 3, alt. 1 mill.; divergence 140°. (Cpr.)
M'l-'itlnn, on Si»nnihjln>- <•<> ••/»'/mo.s/'.< < i'i:.. ( 'at. Ma/at. Sh., p. 1<I2.
< III l"\.
•///, /•;./.>•/ ///.« kTiLia Reeve, PL W I, 84,
Shell OVftte, valvr< very e|..<ely elevately -iriatrd t li roiiL'hoiit ,
ad there inn rarely, bifurcately-divergent, intfi
rather exeavated. \\\ Q, vell<»\\i.-li in the middle, \\ith nar-
row transverse im-en bands. Ligament .~<|iiamately coriaceous,
scales pair >ea irreen.
A peculiar smoothly bronzed shell, painted across the middle with narrow hands or ripples of green. (Reeve.)
•sima} ./•///'///.
C. aqiidtilis REEVE, Conch. Icon., f. 7-'5.
Reeve gives no locality for this species. The figures on my plate are copies of his.
Carpenter writes as follows of Reeve's type specimen : One spec- imen made up of two, only the valves stuck together. I counted just eleven scales in one corner, though Reeve describes and figures it as complete. The very insertion-plates are in great measure rubhed off. It may equal my C. densiliratus in poor condition. Anterior valve having 10, central valves 1, posterior valve 1:5 slits ; teeth pectinated ; eaves short. Shell rather elevated, the dorsal ridge sharpish. Central areas with extremely close fine parallel striae, jugal area not defined. Lateral areas not elevated, having 1 ^ radiating lines, extremely close and fine, as on central areas, but rather more developed ; the end valves similarly sculptured, mucro in front of the middle; posterior slope very concave. Marked "? Japan"; and the habitat of a specimen sent by Damon for pur- chase is Tsu-Hina, Japan. The valves alone, without -'irdle, and irregularly placed measure:
Length 40, breadth 23 mill.; divergence !<)."> .
C. PKNsiuuATrs Carpenter, n. sp.
Shell oval, solid, elevated, the jiiu'iim acute : mucro scarcely prominent, subantcrior. Ashy or pale bmwii, irregularly clouded with chestnut or black, often eleirantly dotted with darker or paler.
Central areas having about *2~> rildet< on each side of the juurum and parallel with it, obsolete at the rid;re: lateral area- well defined, having S-10 line, sometimes bifurcating; end valve< having *: such line.
170 CHITON.
Inside: anterior valve having 8 ; central ralvefl i. posterior valve 18 slits; teeth normal, very closely pectinated ; sinus narrow, havinir about 1 1! minute denticles.
idle unicolored or tessellated, bearing normal imbricating scales which here and there are very minutely Mriatulate.
Length :>s, width 33 mill.; divergence 110°.
,I<i}»in (Mus. Cum., no. 16.)
This species, says Carpenter, from whose J/N. the above descrip- tion is taken, is easily recognized by the very close ribs, arranged like miniature whale bone.
C. MARQUESANUS Pilsbry, n. sp. PI. 36, figs. 98, 99, 100.
Shell oval-oblong, depressed, obtusely carinated. the side-slopes nearly straight. Surface smooth and polished on the central, granose find Itisterless on the lateral areas. Color dark olive-green, almost black on the lateral areas and end valves.
Lateral areas but slightly raised, sculptured with about seven uneven and unequal rows of separated low warts, and under a lens seen to be covered with a minute granulation ; central areas shining, having a few low growth-wrinkles and covered with a partly effaced microscopic granulation. End valves closely granose in indistinctly radiating pattern; mucro near the front margin of the tail valve.
Interior light blue, stained at sinus and under the beaks with purple-brown ; sinus rather shallow and toothed. Anterior valve having 21, central valves 1, posterior valve 25 slits.
i. lie dark green, covered with convex scales, which in the middle of its breadth are larger and carinated.
Length 46, breadth 26 mill.
M.ti'tjiir.nta Is. (Garrett.)
The papillose lateral areas, smooth central areas and uniform dark olive-green color are the more striking features of this species. The large number of slits is also noteworthy. The specimen before me was presented to the Academy by the late Andrew (ianett, and it was labelled " C. marqnesann ; " but whether thi> name was given by Garrett or by Tryon I do not know.
C. PBBVIKIDIS Carpenter.
Shell small, narrow, elevated, thejuirum acute: color an im green. Entire surface very minutely scaly under a lens: lateral areas and cud valves radially I irate, tin- line obtuse, little con- spicuous, 4 or ~) on side-areas, 2"-L'"> <>n end val\ ' iral areas
(Ill : 171
having about 1 '_' little impressed, di>lant siilci, parallel to tin- <i
Mucro anteriorouboentral, moderately pi p
having *-'•> slits in end valve-, I in median valves; leetli a deeply peetinated -hurt; .-inns wide, Mat, toothed. (Jirdlc
furnished \vitli large, solid, imbricating but Mriated Males. Length Hi, wi.lt h 6$, alt. .°» mill.
TaM
C/ilfnn ( Loj,hi/rii.^ itt'i-viridi* CIM:., I*. /. S. 1M'>.~>. p. 511. L»/>li'j- ri(.-i ptrviridit PEASE, Amer. Journ. Conch, vii, p. I'M.
A solitary s])ecimen of this interesting species is very like ( '. v!re«- Kve. in general appearance: but the mantle of tiiat species is nearly smooth and the valves scarcely sculptured. This shell a uniform bright green. It has the aspect of Le]n'dltj,/n.nru.< | Lepid- ozona] ; but the insertion-plates though sharp, are deeply pectinated. It differs from most other Chitons in having the scales di>tinctly striated, as in C. 8friato«f]uamosus. (Cpr.)
C. P.URMANUS Carpenter, n. sp.
Shell elevated, with acute dorsal ridge ; olivaceous or red, Imciny a white blotch <»i the tail vahe behind the mncro.
Whole surface of the valves finely quincuncially granulated ; central areas havinir nlmut '20 .<har}t mid distinct rib* <>n c<«-I> parallel to the dorsal ridge, upon which they are finer and cl lateral areas having 3 to 5 roiv* of stout granules, some of the rows not reaching to the apex. Knd valves having -'"> (or fewer) rows of stout granules. Mucro of the tail valve median, the slope behind if very concave.
Interior having 8 slits in the anterior, 1 in the median, 1 1 in the posterior valve; teeth sharp but distinctly pectinated : » aves -hurt.
Girdle covered with rather roundish oval scale.- of larue >i/e.
Length 19, breadth l<).l mill.; divergence %°.
< 'u'i*f nj AfiL-'i/i. />Y///V/ Jtui'inuh, under st«»m-s at lu\v water.
The British Museum contains four sj)ecimens, of which three are olivaceous, the other red. The above description is from ( ar- penler's .1/N.
//'/, JNV?r Zt'itliDnl.
The S])ecies of tli re mostly of moderate or small -
and generally the muem is central and the scale- mieroscopicallv
striated.
1,1' CHITON.
C. QUO vi i I. PI. 37, figs. 6, 7, 8.
Shell oval, rather elevated. carinated, the side-slopes straight. Surfac.- having a smooth and polished appearance luit very finely striated. ('»!»,• generally a veni '/a/7; olive-green, hut sometimes yelli)\vish brown marked with olive on the sides and ends, or clear yellow with rays of olive or brown.
Lateral areas slightly raised, sculptured with numerous narrow, delicate and slightly erenulated radiating threads. Central anas covered with still finer longitudinal striae. End valves sculptured like the lateral areas, the two about equal in si/e ; ninero of the rather raised tail valve a little in front of the middle.
Interior sky-blue, marked under the beaks with olive-brown rays. Sinus rather square, finely denticulate. Anterior valve having 9- 10, central 1, posterior 13-14 slits; teeth erenulated outside.
Girdle covered with smooth convex imbricating scales, mostly li.irht blue, but often having dark brown scales mingled with them.
Length 37, breadth 22 mill.
.1 iK-klnml to Dunedin, New Zealand, in pools under stones, between
ti«les.
Chiton rirnHs Q. & G., Voy. Astrol. iii, p. 38^., t. 74, f. 23-28 (1834). Not Chiton e.rtn* r/Y/<//>-, hifn* c" >/'//'///* of Chemnitz, Con- chyl. Cab, viii, p. i>77, t. 94, f. 794, 795 (1785), nor t'A. viridit Sprn.irler, if. r. — C/'itnn (jnoyi DESH. in Lam., Anim. s. Vert, vii, p. . 1836).— Ki.i:\ i, Conch. Icon., t. 13, f. 68 (1847).— Chiton glawsu* HITK.N, Man. N. Z. Moll., p. 112 (1880.)
? C/tifon (/fa urn* GRAY, Spicilegia Zoologica j)t. i, p. 5 (1828). — ': /.--//A >/ /•//* r/l<mni8 ANGAS, P. Z. S. 1867, p. '2'2'2.
This species differs from all other true Chitons of New Zealand in its finely sculptured, comparatively smooth surface, resembling in this respect the t '. magnificat of South America. It is a well known New Zealand form, and has also been reported fr-nn Port -Jack.-oii, Australia, by . \ii-a-, under the name £/«"<•">•; but I have not been able to confirm this by the compari-on nf -pecimens from the latter locality, which may safely l>e omitted until authoritatively con- firmed.
The locality of Gray's ('. ylnim.* was unknown, he did not figure hi- -pccimen, which had lost its girdle, and lie states that it was
whit.- in-ide. -Ian- outaide, The identification ofQaoy and
(iai II d. -cril.ed aiid fi^ureil shells from New /.'aland with
« III : 17-".
<ir;i\ UB therefore highly hypothetical; rsp»-ri:illy -in-
..in- leemfl l«> have seen Cray's type, and its ijrnrrir eharaeters, are wholly unknown. I hav«- never leeo a "gb|UCUI linen
of this species "wluteioside;" they arc always blue. The cbi
of name made l>y Deshayes must be adopted on account oi earlier ('. riri'H* of Spender.
('. PELLI88ERPENTIB <,)iioy & Gaimard. PI. 37, figs. 14, 15, 16, 17,
18.
Shell oval, rather elevated, hardly cari nated, the side-slopes some- what convex. Surface lusterless. Color a rather dull and din-y olive or olive-green marked with black along the ridge and on the sides of some valves.
The lateral areas are moderately raised and sculptured with 3 or 4 roir* of Distinct tubercle*. Central areas having *tron</, irregular (jn>irf/i irrinklc*, <unl fine longitudinal riblets. Anterior valve larger and much more elevated than the posterior, both being sculptured with numerous regular rows of distinct tubercles, the rows increasing by splitting. Posterior valve depressed, the low mucro in front of the middle.
Inside blue, indistinctly blotched with olive-green. Sutural- plates rounded, the sinus broad and deep, smooth or hardly dentic- ulate. Anterior valve having 12, central valves 1, postejpor valve 12 slits ; teeth blunt, pectinated. Eaves broad.
Girdle wide, alternately light and dark; scales (pi. 37, fig. 17) rather large and wide, often showing a slight tendency to carination in the middle, microscopically striated.
Length 30, breadth 23 mill.
Heiv Zealand.
Chiton pelliserpentiH Q. & G., Voy. de P Astrolabe, Zool. iii, Moll., p. 381, t. 74, f. 17-22 (1834).— DESK., in Lam., An. s. Vert, vii, p. 508 (1836).— Chiton j>elli*-«erpenti« KEKVI:, Conch. Icon., t. 15, f! 84.— HUTTON, Cat, Mar. Moll. N. Z. 1873, p. 4C : Man. N. /, Moll. 1880, p. 111.— HADDON, Challenger Polyplac., p. '2'2.
This is one of the most abundant New Zealand Chitons. Its sculpture is frequently obscured or lost by erosion. C. sim'/nirl is closely allied, but it differs in color-pattern, in the poll." licit central areas, whilst the surface of pelli«-*erpenfis is lusterless, and in the sculpture of the central areas. The median valves of pellisserpenti*
174 i HITON.
are rather stronirlv arrhed hack ward, and the broad sinus is remark- able for the absence or obsolescence of teeth. The interior, except just behind the .-inns, is smooth ; the callus in each valve is heavy and smooth. Figures 14, !•>, 17 arc drawn from Auckland, X. /. examples, furnished by Mr. < J. W. Wright.
C. SINCLAIRI Gray. PI. 36, figs. 1, 2, 3.
Shell oval, rather elevated, the dor*«l ridge rounded, side-slopes rather straight; brown-black, each valve irregularly and raggedly Hh whiti*h; the head valve pale with dark rays. Some- times the white predominates.
The lateral areas are raised and sculptured with three or four i-'id luting grano«e rib*, often *nbobsolete. Central areas xmooth in the middle except for a few growth-wrinkle*, but having fine .«hort lougitu- •<> the ."life." in front of the diagonal line. These riblets are sometimes almost obsolete. Head-valve sculptured at first with about 15-18 granose riblets, but as these have a tendency to split as the valve grows, the number in a grown specimen is usually 24-30. Tail-valve having a low, obtuse mucro, decidedly in front of the middle.
Interior bluish. Sinus rather wide, denticulate, the area behind it porous. Anterior valve having 11, central valves 1, posterior valve 14 slits; teeth obtuse, strongly crenulated. Eaves broad, _y.
Girdle (pi. 36, fig. 3) covered with large, convex scales, which are very finely, sharply striated.
Length 28, breadth 18 mill.
Length 17, breadth 11 mill.
New Zealand (Sinclair, Hutton, Wright.)
Chit"n ."'nn-lnu'i ClHAY, in Dieftenbach's Travels in N. /. ii, p. 263 (1843).— HUTTON, Trans. N. Z. Inst. iv, p. 177 ; Man. X. /. Moll. p. Ill n«.sO).— SMITH, Zool. ' Erebus' and 'Terror,' p. 4. t, 1, f. 17.— REI-:VE, Conch. Icon., t. 22, f. 143.
The smooth, polished central areas, grooved only al..ii'j the
• nal line at t he sides, and the granoa6»lii>bed lateral area< and
en 1 valves are characteristic, and remind one of the \Ye.-t Indian ( '.
The black-and-white coloring also is rather constant. The
ivas varies greatly in stn-n^th. This s-pecies has been reported from Tasmania, but mi doubtful authority.
' III ( '. i Souverbie, I'l. <'»">. il^. •'!, 4.
Shell ovate-ohlonir, the hack earinatt-d, nmhoiMS HihroMi
-ii «.r yrllowish-ivd, with lon<rit udina I more or ]e.~s pallid and more or less numerous spots. Knd vnlvt-s oi •namentcd with ahoiit L'H radiatin. luhercles (some of tli<
being shorty intercalated between the other-); lateral areas having three scries of tuherdes and a fourth intercalated shorter series. Central areas sculptured on each side of the smooth dorsal carina with impressed, suhohliquely longitudinal grooves. Girdle leathery and scaly. Dimensions, exclusive of the girdle, which is very incom- plete in our two examples (probably immature) ; length 19, breadth mill. (6W.)
Art J*/nnd, N. Caledonian Archipelago (Mus. Bordeaux.)
Chiton decolor Souv., Journ. de Conch. 1866, p. 252, t. 9, f. 1, la. — C. miniacens CPU., J/\, Mus. Cuming.
Carpenter's unpublished species seems to be the same as this, although until the types of discolor are examined, we cannot be certain. Carpenter's description here follows:
C. miniacen* Cpr. Shell elevated", oval, the jugum acute ; vivid vermilion, the margin tessellated with paler. Mucro median, little el'-vated. Entire surface minutely punctate; central areas having about 25 subparallel grooves on each side, obsolete on the dorsal ridge ; lateral areas elevated, bearing 3-4 strong, radiating line, which are strongly nodose. End valves having about 20 line. Interior: anterior valve having 8, central 1, posterior 10 slits; teeth deeply pectinated; sinus wide, minutely denticulated. Girdle covered with normal imbricating scales.
Length 27-1, breadth 20 mill.; divergence 100°.
New Caledonia.
MILS. Cum., no. 59. Easily recognized by the strong sculpture and brilliant vermilion color. (Q>r.)
( . MTRICATUS A. Adams. PI. 37, figs. 12, 13.
Shell oblonir, much elevated in the middle; black-brown and white variegated. Knd valves and /titrml urem* n/'/m/r/// i-illictl, the ribi Ornamented n'if/i dcmlcd acute f/niinn: tail valve umbon- ated in the middle. Central areas longitudinally deeply lirate, the umhoiics smooth, elevated, somewhat produced. (Jirdle scaly, the scales mucronatcd, imbricating, with subenrt apices.
1 , t ; ,in
Tliis species is remarkable for the somewhat triangular imbricate BOalefl of the ligament ending In slmrp i«>iutc<l nmcmnes; the liga- ment is tessellated with pale fuscous and dark brown ; the ribs on the lateral areas are four, inurieated with sharp granules. (Ad.}
Sy<li-:. V. N. W<tlest Australia, under Btonea at low water. (Strange.)
Ctntnn » A. AD., P. Z. S. 1852, p. 91, t. 16, f. Q.—Lophy-
nis MurtMtua AN..AS, 1>. /. S. 1865, p. 186; 1867, p. 222.— Clnt»n /ini'ins and C. carn»*n* CIM:., J/.s'N.
Varies in color from dull green to orange and bull'.
Carpenter examined Adam's type of this species, and ascertained it to be identical with his own unpublished (.'. li»i<tiis; the descrip- tion of which here follows:
Shell oval, elevated, the jugurn acute; mucro median, subprom- inent ; olivaceous, maculated with paler ; entire surface minutely punctate; central areas having about 14 grooves on each side, obsolete in the middle; lateral areas having two riblets, sometimes bifurcating or with another intercalated, furnished with strong acute tubercles, interstices smooth ; end valves with 10-20 such riblets. Interior : anterior valve having 8, central 1, posterior valve 9 slits; teeth normal ; sinus moderate, with about 15 denticles. Girdle furnished with large and small wide, distinctly striated, elevated, acutely pointed scales. .
Length 23], breadth 12*, divergence 100°.
The points of the striated scales project, as in Isc/i. australis, so as to give the girdle a rasp-like appearance.
Yar. nurnntlns Cpr. Shell smaller, pale orange colored, dotted with more intense; posterior valve with 10 slits.
Length 17*, breadth 10 mill.; divergence 100°.
Like the preceding in all important character?, but differing remarkably in color and pattern.
A form in which the sculpture of the side areas is less developed received the name carnosns ( 'pr. The original description in Carp- enter'- .1/v !>efore me, indicates the following as the m<»t important characters of cnrnosmt : Central areas having about 18 suhparallel -ulci on each side, more prominent toward the margin, obsolete toward the jugnm ; lateral areas and end valves having irregularly (at the sutures strongly) nod.»e wrinkles, 4 in number on the >ide areas, 22 on the anterior, 14 on the posterior valve,
i 111 1.7
hi fin-cat iii'j:. Interior: anterior valve with*, central 1, post
valve- LOsliti, Length 80, breadth ir> mill.; divergence l<
Ka-ily rec«»_i:ni/ed by the ilesliy color and small, beaked, ma:
scales; the side sculpture of /imotw (with which this species agrees in the scales) 11 very diflerent in pattern. (Cpr.)
(\ c \\\\.\<-( \.\v\ > (^imviV <iaimard. 1M. .'Hi, li.urs. 4, 5, 6.
Shell small, ohloni:, N//V///J//// elevated, carinated, the side-si* straight, steep. End valves and lateral areas pink, central areas yellowish . dorsal ridge pink with an olive-green stripe on each side. Sometimes olivaceous, or olive and rose.
The lateral areas are strongly raised and sculptured with 4 or ."> radiating ribs which are regularly cut into low beads, and which often split toward the lower margin. Central areas having a narrow smooth space upon the ridge, sculptured on each side with about 16 strong longitudinal ribs, separated by deep intervals ; posterior mar- gins of valves crenulated. Anterior valve having about 22 granose radiating ribs ; posterior valve having about 16 granose radiating ribs, the umbo slightly in front of the middle, the slope behind it a little concave. Interior whitish; sinus rather deep and narrow.
Girdle covered with compactly imbricating, convex, shining obso- letely striated small scales (pi. 36, fig. 6.)
Length 14, breadth 11 mill.
Ta*man Bay's (Q. & G.), and Stewart Island (Hutton), Xew Zea- land.
Chiton canalicnlatus Q. & G., Voy. Astrol. Zool. iii, p. 394, atlas, t. 75, f. 37-42 (1834).— Chiton stangeri REEVE, Conch. Icon., t. 22, f. 150 (1847).— Chiton insculptus A. ADAMS, P. Z. S. 1852, p. 91, t. 16, f. 4.— ef. HUTTON, Man. N. Z. Moll. 1880, p. Ill, 112.
Allied, in its acutely elevated contour, to C.,/".'/"*"^, but differing maikedly in the granose-ribbed lateral areas. It is usually very brilliantly colored with rose-pink and buff) but olivaceous torn i- occur. The latter may be distinguished from C. *uit'lairi by the differently sculptured central areas. Professor Hutton (in lift.) suggests to me the identity of stangcri and inm'iiljtt'i*. The latter seems to agree altogether with (Buoy's oanaKcMlatut.
The girdle-scales (pi. 36, fig. 6) are smaller than in ('. jiignsus, and they are much less distinctly striated than in ('. ,s///" pettiuerpentis.
178 ( II1TON.
( '. .injosus Gould. PI. 36, figs. 91, 92, 93, 94, 95.
Shell oblong, much elevated, carinated, the side-slopes straight and steep. Central areas sulcate at the sides, smoufli in the middle, literal urea* smooth. Color light green, the ribs of the central <
>/e, lateral areas with fine alternating concentric lines of yellow and green.
The lateral areas are strongly raised and smooth, painted with close lines parallel to the dorsal keel. Central areas having a smooth triangle in the middle, the sides sculptured with 11-14 strong rounded orange colored ribs, separated by deep, blue intervals of the same width. Head valve smooth, concentrically lineated ; tail valve concentrically lined at the sides, having a broad triangular buff or orange ray behind, extending across the girdle ; apex project- ing slight li/ behind the middle, posterior slope strongly concave.
Interior blue-white, the sutural plates white. Sinus narrow and angular, denticulate. Anterior valve having 8, central valves 1, posterior valve 12 slits ; teeth blunt, pectinated. Eaves spongy.
Girdle (fig. 95) buff and greenish, irregularly alternating, covered with compactly imbricating, polished convex scales, which are obso- letely striated. Length 35, breadth 20 mill.
Port Jackson, Sydney, N. S. Wales, Australia.
Chiton jagosus GOULD, Proc. Bost. Soc. N. H. ii, p. 142 (1846); Expl. Exped. xii, Moll. & Sh., p. 317, atlas, t. 28, f. 430 (1852).— SMI in, Xool. Coll. H. M. S. 'Alert/ .p. 78 (1884).— HADDON, Chall. I'olyplac., p. 22 (1886).— Lop hyr us jugosus GLD., Otia, p. 3, 242 (1862).— ANGAS, P. Z. S. Lond. 1867, p. 222.— C/nton concsntricns Ki i:vi:, Conch. Icon., t. 16, f. 95 (1847). — Lophyrus concentricus ANGAS, P. Z. S. 1867, p. 221.
The peculiar and beautiful coloration separates this species from its allies. The second valve is frequently blood red, or blotched at the sides with dark sepia; and occasionally all or many of the valves have blotches of buff interrupting the longitudinal color-lines. The light triangle radiating backward from the- uinho of the tail valve is present in every specimen I have seen. The tail valve, indeed, i « in Sin Is one somewhat of that of an irregular Chiton.
Tin- paintiiiLT of tin- lateral areas gives the impression that they are longitudinally ribbed, as Reeve and An.iras havr dcscrilx-d : but even in Reeve's tyj>e8 these areas are quite .-month, as they are in all the specimens I have seen.
179
This sp.-eie- has hem reported from New Zealand, hut probably
incorrectly,
('. ITI.VIN \ rrs ( 'arpenter, n. sp.
Shell small, oval, suhelevated, with acute jiiiruni : IMIHTO median ;
apie»-s ot' the valves prominent; olivaceous and !>ro\vn variously
clouded and irregularly painted. Kntire surface minutely punet-
ulated ; mitral areas hari n</ <t/>out.l6 deep su lei on each side; lateral
«','// (lejiiH'd, H en rh/ smooth, as are the end valves also.
Interior: anterior valve having 10, central valves 1, posterior valve !> slits; teeth acute, deeply serrated ; sinus moderate, dentic- ulate.
( Jirdle covered with large smooth scales.
Length 0, width 4* mill.; divergence 110°. (Cpr.)
New Ireland (Mus. Cuming, no. 78.)
Distinguished from Inzonicus by the smooth scales and side-areas, which display a velvety appearance under the microscope.
C. yEREtis Reeve. PL 36, figs. 96, 97.
Shell oblong-ovate, angularly raised in the middle ; valves rudely impressly striated throughout, umbonal eminence smooth. Dull green ; ligament granosely coriaceous.
The color is a uniform dull green except along the rubbed umbonal summit, where it has a copperas hue. (Rve'}
New Zealand (Earl.)
Chiton cereits REEVE, Conch. Icon., t. 7, f. 36 (1847). — Chiton (Leptochiton) cerens SMITH, Zool. Voy. ' Erebus ' and ' Terror ' Moll, p. 4, t. 1, f. 9.— CA. siculoides CPR., MS.
This species has been referred by Smith to C. siculus Gray. The locality requires confirmation, as it rests solely upon Cumingian specimens. Hutton (Man. >.'. 7. Moll.) reprints Reeve's diagnosis without comment.
Carpenter's notes on Reeve's type are as follows ; Central areas having about 20 furrows on each side, not deep, continuing until they are rubbed off in the middle; lateral areas having 4-8 divari- cating riblets, much worn, broken up by the concentric ruga of growth; crenate at the sutures; end valves with about 30 riblets. Mucro in front of the middle, posterior slope concave. Interior
180 < I II TON.
bluish, sinus with ~>-13 denticles, deep, narrow; girdle scales stout, roundish. Length :J!», breadth 23, divergence 94°.
One specimen, New Zen land, in Mus. Cuining.
Species of the Mediterranean and African Seas.
The species are allied to those of Australia and New /ealuml, the iiiucro in many of them being central, and the scales striated.
C. OLIVACEUS Spengler. PL 35, figs. 87, 88, 89, 90, 91, 92.
Shell oblong, elevated, carinated, the side-slopes strain lit. Surface ribbed and microscopically punctulate. Color very variable ; either black, brown, scarlet or olive-green, unicolored or clouded or mottled.
Lateral areas raised, sculptured with 4-6 flat Ion- rndi'tfi:ii/ ribs, the posterior rib widest, separated by narrow shallow grooves. Central areas having a smooth triangle on the ridge of each valve, the sides (pleura) bearing strong longitudinal ribs, which become stronger toward the outer margin. End valves having low radiating riblets. Tail valve having a conspicuous central apex, the posterior slope somewhat concave.
Interior light bluish, marked with brown rays in each valve. Sutural plates rounded ; sinus deep, square, denticulate. Anterior valve having 7-8, central valves 1, posterior valve 8-10 slits ; teeth blunt, pectinated. Eaves spongy. Girdle wide, banded with alternate light and dark, compactly covered with minute smooth, convex scales. Length 36, breadth 20 mill., often less.
Mediterranean and Adriatic Seas ; Cape Verde Is.
Chiton squamosus POLI, Test. utr. Sicil. i, t, 3, f. 21, 22 (171)1) and of PAYRAUDEAU, COSTA, and PHIL., Enum. Moll. Sicil. i, p. 106, t. 7, f. 3; and of Granger, Moll. France, p. 170, t. 12, f. 16 (1885). Not of Linne*. — Chiton olivaceus Sn:v.i.r.K. Skrivter af Naturhistorie-Selskabet, iv, p. 75, t. 6, f. 8a-c (1797).— Jeffreys, Rep. Asso. Adv. Sci. 1873, p. 113. — MONTEROSATO, Enum. e Sinon. p. 17.- Bn>. DM i/. et DOI.I.F., Moll. Mar. du Rouss. i. p. 489, t. 61, f. 4-6, t. 62, f. 4.— LOCARD, Coq. Mar. des Cotes de Fr., p. 232 (1892).— Ch. , EtaBO, Hist. Eur. M.-rid iv, p. 268.— Ti m 1:1.
Bull, della Soc. Malac. Ital. iii, p. 145. — Chiton siculus GRAY, Spicil. 7,ool., p. .", ; Pun.., Knuiii. Moll. Sicil. ii, p. S2.— Wrix- KAUKI, Conchyl. «l<-s Mittdm. ii, p. 408.— REEVE, Conch. Icon., t. ">; t. 16, f. 97 (lowest fig.); t. 19, f. 12l.— Gli/mnopl>ix
< III
K". mm:., NOIIV. . \n-h.du Mn~. 1^*1, p. 242, ' 'A///,// ;,/,/// |)i-n. (not IMiil. I de Morfe, iii, |>. 132; Lamk. .-.lit. Dl,., vii,
]). .~>(U. — C. #<iniiiiimiifomi* I )ni.i.i I "s. ( ';il;il. I'alava-. |
Doubtful synonyms: /,«/>/////•//>• .<irn/ H* forma africana Rod 1 1
BBUNE Journ. de ConchyL (3) \\i, p. -I'J M881). — Chiton str
Ciiir.i:i:«.niM .UN. BBT78IN1 I psa ('liicr. ( 'onchyl. p. 44 (1870). — r//. fstinirii ('1111:1:., MS. liurs., f. /•., p. -I-").
This common Mediterranean specie.- is very variable iii color, as the ii.irim-s show, hut quite constant in sculpture. Tlic valves are generally very much elevated, like a gothic roof. The prominence of tin- mucro or heak of the tail-valve, and its central position, are characters showing the strong bond of affinity between olivacens and the Australasian species, and sundering it from the somewhat similarly sculptured West Indian forms. Issel and the authors of Molln&nn.'* Mai-ins du Roussillon classify the color-forms of this species into two groups : (1) those which are variously marbled and spotted, and (2) those which are unicolored, forming the
Color- var. unicolor Issel. Entirely white, tawny or red. It is likely that C. rnbellus of Nardo was founded upon an individual of the last color.
I regard it as probable that the Lepidopleurm corallinus of Risso (Hist. Nat. TEur. Merid. iv, p. 268) was based upon a red example of C. olivucens. Monterosato has suggested that corallinus is the same as rubicundus Cosfa+scytodesma Scac.,-\-freelandi Fbs.-f- pulc/tellus PblL-\-philippii Issel (see Journ. de Conch. 1878, p. 146). This identification seems to me to be quite inadmissible.
Rochebrune describes a ' forma ' Africana as follows : Allied to L. siculus, but differs in having the valves obtusely carinated, the sulci of the .central areas very delicate, straight. Length 26 mill. Promontory of Cape Verde, and Table Bay, Cape of Good Hope.
The reference of this form to the present species is doubtful.
C. AFFINIS Issel. PI. 35, fig. 93 (enlarged.)
Shell oblong, subcarinated, smooth, painted with various colors ; end valves radiately ribbed, the front valve having about 21 ribs, concentrically striated ; the other valves having longitudinal arcuate grooves ; lateral areas narrow, triangular, transversely tri- sulcate. Girdle minutely scaly.
Length 18, breadth 11, alt. 6 mill. (Issel.)
GnlfofSnez.
1M> < IIITON.
SAVK.NV, iWript. de 1'Egypte, Gasterop., t. 3, f. 9.— Chiton Malar. Mar Kosso, p. 234 (1869). — C. .«<V/////x <iray, COOK i- . Ann. Mag. N. H. 1885, p. 275.— E. A. SMITH. IW. /ool. Soc. Lond. 1891, p. 392.
I have not seen this species, which is considered by Cooke and Smith to be synonymous with the common Mediterranean C. x/V///*/s of Gi iceua Spengl.). Smith says that it " may be regarded
as a stron.L'ly marked form of the Mediterranean species. There is also a species found in New Zealand, C. siculoides Cpr., MSS.= C. wens Reeve, which is also inseparable." As I do not know that Mr. Smith's opinion is founded upon a study of the inside as well as the external characters, I prefer to retain C. affinis as a distinct species for the present, although it is certainly closely allied to C. olimren.4. Issel gives both figs. 8 and 9 of Savigny's plate as illus- trations of his species, but his description applies only to figs. 9. Savigny's figs. 8 represents, in all probability Callistochiton adenensis Smith.
C. RUBICUNDUS Costa. PL 45, figs. 73, 74, 75.
Shell similar in form and color to Trachydermon rnber, but much smaller; subelongate, much elevated, the valves beaked; dorsal ridge very acute ; mucro median, elevated. Entire surface micro- scopically granulose, the central areas having spaced, longitudinal parallel sulci, 6 to 9 on each side; lateral areas snbelevated, smooth.
Inside having 8-10 slits in the anterior valve, 1 in the central valves, 9 in posterior valve ; teeth acute, but all distinctly serrated : eaves moderate; sinus moderate; sutural-plates joined by a si.iall serrated lamina.
Girdle regularly imbricated with large, solid, smooth scales.
Length 8$, breadth 5 mill. ; divergence 80°.
Length 6, breadth 24 mill.
A, Philippi) ; Dalmatia (Mus. M'Gill Coll. and Acad. Nat. I'hila.)
Chitnn rnb,'rundu8 O. G. COSTA, Catalogo sistematico e raLri«mat«> de1 Tortaori d«-lhi due Sicilie, p. i, iii, t, 1, f. 2 (Naples, 1829); Fauna di Napoli, Aniiu. Mulli, Chiton, p. 8. — Chiton j»<l<-hf//ti.< Pim.irri, KIIUIII. M..I1. Sicil. ii. p. 83, t. 19, f. 14.— Chiton rubella* Cnt., M*. olim, and C. /'•„/•,////////.< Cri;.. V\
Doubtful synonyms: Ch. free law fi PORBEB, I{»-|>. Ai-ir. Invert., in K«-p. i::th in.M-tin- Urit. Asso. Adv. Sci., for 184:;. ,,. i-s'^j (1844). — C. scytodern .\\, < '. /,// /'//;>;, //
. 111 roiTi
The prominent features of this little sprri»- >lor,
Lrreat elrvatioli. like a -"thie roof, and the sculpture.
Thi- ifl imt identical with the LepidopleUTUA mr<i//imi
. as Montero.-ato has said. It is impossible {'or me to believe that Kisso would have used the words " avec le- .'l.'vat i«.ns lah'rales bisul<pi«'es " if he had hern desci'ihinir ( '. riiln'riiinhi.<. The identi- fication of the learned authority on Mediterranean -hell.- \\as not founded upon an examination of UHSO'S type.
('. HAM vi Koehehnme. I M. 35, figs. 85, 86.
Shell ovate-elongate, carinated, green, /xiintrd loiif/ifudlimf/i/ ////'/ regularly u'ith altti'iiafhiy linr* of n'hite, bine and huff. Head valve l-itfi-'il areas and posterior areas of the tail valve sculptured n'ifh *frong concent r ii- ridges, which are irregular and as if imbricated; central areas having 7 utrong, iridc, obliquely curved ribs, the middle smooth. Girdle scaly, scales rounded, very shining.
Length 23, width 12 mill. (Rochebr.}
Strait of St. Lueie, Cape Verde Is.
Gymnoplax hamyi ROCHEBR., Bull. Soc. Philom., Oct., 1881 ; Nouv. Arch, du Mus. (2) iv, p. 242, t. 17, f. 13a, c (1881.)
Allied to C. concentricus Reeve, but distinguished by the imbrica- tion and irregularity of the concentric Ftrine of the end valves and lateral areas, by the width and small number of grooves on the sides of the central areas, and the absence of a mucro on the tail valve. (Eochebr.)
The references to the figures of this species and C. insularis are transposed in Rochebrune's publication.
C. INSULARIS Rochebrune. PL 35, figs. 83, 84.
Shell ovate, elongate, subcarinated,the carina obtuse ; olivact- sparsely spotted with white; anterior valve and posterior part of the tnil rnli'e Sculptured n'itli i-ndinti/ig, interrupted, feeb/i/ grilling r//»-; median valves having the centra/ urea* *innntli in the middle, *nlc<ited at the */Vf.?x, the «H/CI H/IC<JH<I/, bmcenJute, pointed at the ends, con- centrically arranged ; lntr,-<il ami* /luring hrnm-hiinj i-ndiufiin/ /-/Ax. Girdle olive marked with wliite spots, scaly, the scales minute. (Hnrh.hr.} Length '11, breadth 1 o mill.
Strait nf St. Vni<-> at, <'"i» ]'>,•>!• A.
Qymnoplax ///.<//A//-/x ROCHKIII:.. Nouv. Archiv du Mus. ('!) iv, p. 243,'t. 17, f. 12«, b. (1881.)
Conijtare ('//. oftvoeeu* 8pengL
1M CHITON.
C. LYRATUS Sowerby. PL 31, figs. 35, 36.
slu'll oval, smooth ; hack Bubangulaied ; lateral areas subelevated, smooth : central aivas longitudinally li rate at the sides; girdle broad, minutely scaly. Length 37, breadth 1~> mill. (Sowb.*)
This shell is ><> thin as to be nearly transparent; it is smooth, ratlin- amrulated in the center, the lateral areas smooth, slightly elevated, the central areas marked with faint longitudinal ribs. The margin is covered with regular, minute scales. The general color is drab, variegated with brownish concentric lines at the sides and reddish-brown dorsal bands on some of the valves. (Swb.)
Jfnltitiit Hiihnoirn.
Chit'm ////•'////>• Sown, in Charlesworth's Mag. of Nat. Hist. 1840, p. 293 ; Conchol. Illustr., f. 126.— REEVE, Conch. Icon... f. 110.
This shell should be compared with w//'//-fV//*/x Orb. and tli.<- .«ini!/i* Reeve.
Carpenter has described a C. xr////A/-/-/'x in MS. from Cumingian specimens of unknown locality. It will probably prove to be a form of the above species.
Reeve reports C. lyr'tin* from Prince Island, West Africa, under stones.
C. DISSIMILIS Reeve. PI. 37, fig. 11.
Shell oblong-ovate ; terminal valves and lateral areas longitu- dinally grooved, smooth in the middle ; variegated with reddish- brown ; ligament granosely coriaceous, tessellated. Approximating in some measure to the C. tu/ijut. (J£mr.)
Ifufiifilt nnkiinirii.
C. f//W//////* RKKVK, Conch. Icon., t. 25, f. 170 (May, 1847.) Reeve s description does not correspond very well with his figure ; and the species will probably prove to be the same as C. mnnrii //>•/.< Orb.
Carpenter notes that in Reeve's type specimen the whole surface is conspicuously quincuncially granulated. The anterior valve has 9, central 1, posterior valve 13 slits; teeth sharply pectinated. It measures, length 18, breadth 9 mill. ; divergence 90°.
C. CAN M:M .Nsisd'Orbiirny. IM. :!4, figs. 77, 78, 79.
Shell oblong: carina smooth, central areas of the valves longitu- dinally sulcated, lateral areas smooth; ends smooth: margin granulate-scaly. Length -J4, width 12 mill. (Orb.)
CHI
The shell is oldon-, a 1 it I le ea ri mite, I ; the intern xillnnf/i nt tin fiiriiiii, iiKirlcrtl nu < nr/i *i<l< //•/'/// *lr<nnj , ':it<'d
l>y deep grooves; the /»//»/•»// <n-«^ an </////•//// .<////»o///, :is well as the end valvrs. The -ii'dle is wide, exten-il.le, covered with little oblong. smooth ami polished scale-, larire.-t in the middle of its width.
The coh>i> are verv variahle : sometimes marbled with Mark and brown spots on a white ground, sometimes with some valves quite Mack or ^roi'ii. the others spotted. Tin- irirdle i> radiated with Mark, gray and white. (Orb.}
CHIHH-II [«. (Webb and ]>erthelot.)
( '. rinmrieii*i« OKI;., in Webh tt Berth., Hist. Nat. des lies Canaries, Moll., p. !W. t. 7, f. 16-11). — Chiton (JLophurw?) riiiini-irii.*!*, SHUTTLW., Bern. Mittheil. 1853, p. 81.
Allied to C. o///wr//x, but differs in having the lateral areas and end valves smooth. The interior, according to Shuttleworth, is green, with spots of rose and purple. This species should be com- pared with C. lifrntti* Sowb.
C. TULIPA Quoy & Gaimard. PI. 31, figs. 43-49.
Shell oval-oblong, elevated, acutely carinated, the side-slopes nearly straight. Snri'nrr #ntonth and polished throughout. Ground- color buff or whitish, suffused and closely mottled all over with red- dish-chestnut, fawn, or purple-brown ; usually longitudinally streaked on the central areas, zigzagged or tessellated on the end valves, and articulated on the diagonal lines with the darker color. Sometimes parts of some valves, or several whole valves are of a uniform dark brown color (figs. 43, 45.)
The central areas are smooth except for slight growth-lines and a microscopic granulation which covers the whole surface. Lutrnil areas /'>// /•<//>"/, flat, rarely with slight radii, smooth. In the excavation at the diagonal line a lens shows a few very short longitu- dinal grooves, in some specimens. Tail valve elevated, //•//// rr///,W wnbo.
Interior very light blue-green, each valve rayed with brown at the beaks. Anterior valves having 8, central valves 1, posterior valves 12 slits; teeth pectinated. Eaves short, spongy, grooved along the teeth. Sinus narrow, denticulate.
186 i III TON.
< iirdle solid, closely covered with smooth, convex scales. Length 43, breadth 25 mill. ; divergence 105°. Length 38, breadth '27 mill.; divergence 100°. Length 33, breadth 24 mill.; divergence 112°.
Cape of Goo<l II»rl .
Cli'itm, tuHjin (JuoY & GAIMARD, Y<>y. de 1'Astrol. Zool., iii, p.
389, t. 74, f. 35-36 (1834).— KRAUSS, Die Sudafric. Moll., p. 37.—
C. t'ljmltinhi SOWERBY, Charlesworth's Mag. of Nat. Hist. 1840, p.
Conch. Illustr., f. 45, and var., f. 85, 86.— REEVE, Conch. Icon.,
t. 3, f. 18.
? C. politits SPENGLER, Skrivter af Naturhist.-Selskabet, iv, p. 89, 17l»7.
A smooth, polished species, excessively variable in color and pattern. The short traces of grooves at the diagonal line are rarely visible without a lens, and are completely obsolete in many spec- imens. The smooth surface and unusual coloring are the more striking characters of the species; but the strongly raised lateral areas and the central mucro at once separate it from C. , etc.
C. RUSTICUS Deshayes. PL 31, figs. 32, 33, 34.
Shell ovate-oblong, depressed, the jugum rounded ; very dark green, much paler beneath.
Entire surface quincuncially granulose. Central areas with no other sculpture, but at flu- ilui<j<>n<il //'//«" th>rr<n-< <>// e<i<-Ii .«'i<l< 10-15 -•Ao,7 l>nf <!,< t, <j moves. Lateral areas swollen, and having n f> n- indistinct) obsolete swelling rib*, or rather, obsolete knobs irregularly coalescing into indistinct ribs; blotched with paler. End valves similarly sculptured and blotched, beak of the tail valve in front of tin middle, the slope behind it a trifle concave.
Interior: anterior valve having !», central valves 1, posterior valve 12 slits; teeth pectinated ; eaves short; sinus moderate, with about 13 teeth.
< Jirdle dark olive, like the valves ; covered with very large stout scales.
Leiurth '24. breadth 15, alt. 6 mill.
Length L'n. bivadth l-'J mill.: divergence 1 15°.
<in<I
. Ill H.N. C. I I>H.. Moll. K. MM., p, 89, t. ft, !'. 1 3, ( ; 1, J).
C, /,'///'/«/'/"'/•« .Mr-, in Mol.iu- i li Mauri-
tius, p. oIKI.
This species has considerable resemblance : l>ut
the lateral arca< and end valves an- le.-s Btronglj Sculptured and the longitudinal rihh-ts arc lacking on the central areas except at the diagonal lines. The above description is from Carpenter's J/>.
C. ANGUSTlco>r\ n> <,Juoy iV (iaiinanl. IM. :51,fii:s. -'IT,
Shell ovate, wide, little elevated, depressed hehind hy the prom- inence of the anterior valve. The third to the seventh valves are excessively narrow, arcuated hehind. with a little median projection, which contributes to form a dorsal carina. The last valve is the largest of all, nearly orbicular; the second valve is next in size, the intermediate valves being about equal. Sutural plates narrow, separated by a wide, flat, sinus ; insertion-plates denticulate. The end valves have striated teeth. The entire interior is a pretty green ; and this we suppose to be the color of the outside, but it is eroded. AVe think it is striated like our C. rtritlf*. The girdle is scaly, the scales oval. Length 22, width 16, alt. 8 mill.
Lie of Fi'min;
C. (ni</n«t;co«t>itn* Q. & G., Voy. Astrol. iii, p. 398, t. 73, f. 4, 4'.
The entire substance of Quoy's description is rather freely trans- lated in the above paragraph. It is very likely that this is merely a greatly worn specimen of C.yW//xxoyyr////x Q. & G.
( '. NKiKoviiMiNS Blainville. PI. 31, figs. 41, 42 (enlarged.)
Shell ovate, moderately elevated, the dorsal ridge obtuse ; black- ish. Mucro in front of the middle, little raised, the slope behind it straight.
Valves obtusely beaked; entire surface minutely quincuiK-ially •rranulated; jugal area smooth, often eroded; central areas having about 30 delicate lirulse on each side, parallel to the dorsal ridge, sometimes eroded ; lateral areas moderately raised, having 6 to 8 delicate granulose riblets, the intervals Hat.
Interior: anterior valve having 12, central valves 1, posterior valve 14 slits; teeth short, obtuse, coar.-ely pectinated; eaves small : sinus wide, flat, 12-toothed.
Girdle covered with solid, smooth, lanre and rounded imbricating scales. Length 17'., breadth 10 mill.; divergence 117°.
•/ H<>i» .
188 ( IIHON-SCLEROCIIITON.
Chiton nigrovirent P>LAINVIU,E Diet. Sci. Nat. xxxvi, p. 538 (1825).— HADDON, Challenger, Polyplac., ]>. 22.— C.operMU GRAY, Spicil. Zool., p. 5 (1828). — HANLEY, in Wood, Index Test. Suppl. t. 1. f. LI.— REEVE, Conch. Icon., t. 22, f. 151.— KK.U--, Die Siidafric Moll., p. 37.
C. TENUISTRIATUS Sowerby. PI. 38, figs. 27, 28.
Shell oval, carinated, the back elevated ; valves all over very finely radially striated; girdle scaly.
Length 25, width 15 mill. (So>r/,.j
A neat little shell of a dark olive-green color, oval, elevated, nearly smooth in appearance, but finely striated ; margin lighter green than the rest of the shell; inside bluish-green. (Sotcb.)
Habitat inihiiinri, (Mus. Stainforth.)
C. tfimlxfrinfii* SOWB., in Mag. Nat. Hist. 1840, p. 291 ; Conch. Illustr., f. 135, 135.
This is apparently a typical Chiton, closely allied to qnoyi or , but it seems to be more elevated than either.
C. MAURITIANUS Quoy & Gaimard. PI. 31, figs. 39, 40.
Shell small, oval, elongated, the valves elevated, carinated, trans- versely finely striated and having lateral areas over which the stria- pass. It is a very dark green, lighter at the ridge, and at the edge of the girdle, which is covered with fine, close, rounded scales, and marked with 18 brown bands. Branchial leaflets about 38 on each side. Length 18, breadth 10, alt. 6 mill.
Mauritius.
r. mawritianu* Q. & G., Voy. Astrol. iii, p. 397, t. 73, f. J-3.— L'j,itli,l,/, a, -ii." mini, -H'mit a* MARTENS, in Mobius' Reise nach Mauritius, p. 300.
Known only by the original description, which is far from being satisfactory. The interior has not been described. It is a more carinated species than C. quoyi, and the striation is in a different direction ; the girdle also being banded with brown.
Section SCLEROCHITON Carpenter, 1892.
'eroeh&m CIM:., .l/\, in Dall, Proc. U. S. Nat. Mus. 1881, p. 284, 287, 289 (no type mentioned.)
Teeth of the tail valve turned forward, blunt and pectinated ; sinus smooth, not denticulate; scales of girdle solid, striated,
uted.
OHITOK i: LDflJ \.
This section or sabgeniu represents a further development of the
AcMiithoplcuroid characters which sonic A uM ralasian ,-peries of the restricted p-nus ChUmi a-.-ume. In ("//. /» ///.•»•/ ,-/» ////'-, lor example, the 'micro is median, the posterior teeth tend forward .-om»-wh;i- sinu- i- smooth or only very ohsoletcly denticulate, and the girdle- scales are striated and rather separated. I" &-i,-,'n<-hiin,i the mucro is -lightly more posterior, the teeth slightly more tilted forward ; the sinus is smooth, and the girdle scales still more separated. ('I. il* could be placed almost as well in Schrncliitnn as in 8. *. ; the necessity of reducing Sclerochiton to the rank of a section under (1liifnn will therefore be apparent. The girdle-scales hear a certain resemblance to those of En<>i>I<x-liit<>n, but this is a purely accidental similarity, dependent upon their separation on the surface of the girdle.
C. MILES Carpenter, n. sp. PL 46, figs. 1, 2, 3, 4, 5'
Shell solid, rugose, oval, depressed, generally eroded ; dorsal ridge rounded, hardly defined ; mucro behind the middle, nearly flat; apices of the valves prominent, obtuse. Ashen, spotted with black-brown. Central areas transversely pretty regularly riigulose, the wrinkles appressed ; lateral areas hardly elevated, moderately well denned, conspicuously rugose, rugae subradiating, granose ; the end valves similarly sculptured.
Interior having the anterior valve with about 11, central 1, pos- terior valve obscurely 9-11, slits. Teeth of posterior valves directed forward, strongly callosed inside above the slits, sulcate outside ; the rest of the valves having the teeth sulcate outside and pect- inated at the margins. Eaves moderate, solid, deeply grooved. Sinus deep, wide, wavy, smooth ; sutural laminae united.
Girdle (pi. 46, fig. 1.) maculated, ornamented with large, solid, more or less separated scales which are striated outside ; no hairs. (Cpr.}. Length 30, breadth 17* mill. ; divergence 130°.
Tnrrr* Sf I'll iff (Mus. Cuniing, no. 42.)
A variety is described as being a little narrower, and blackish, hardly maculated.
Section KADSIA Gray.
i;,i,l*i>i ( JIIAY, P. /. S. 1847, p. 126. Type Ch. /*/,•//- Girdle and shell like C/iiti>//, except that the insertion-plates of the intermediate valves have two or several slits.
I'.il) CH3TON-RAD8IA.
Carpenter's opinion of the small importance of the character upon which this Lrroiip is founded, is fully supported by the material studied by myself. lie writes as follows: "The bi- or tri-slitting of the lamina1 appears to me a character of very secondary impor- tance, as Ix-iiiLf merely numerical, not structural, and as being very variable even in the same specimen. In one specimen of Dr. Gray's type which I received from Mr. Cuming, only one r<i/r> /mil fm> >•///.<
»-h >/'/<; most of the other valves had one only ; sometimes a second slit was seen on one side. For such a specimen it would have been as useless to establish a genus as for C//. i'!i-i/n/ntu.«, or for C.
a 1 1 in which Dr. Gray found the same abnormality (vide P. Z. S. 1847, p. 127). Another specimen of C. burnt^ii had the valves either with»one slit or with two slits on each side, or with one on one side and two or three on the other. Under these circumstances I cannot regard the number of slits as a generic character." Compare alse the notes under C.
Key to species of Ji<n1*i'i.
<i. Surface smooth, goodwill.
tin. Surface sculptured with riblets.
b. Ribs strong and coarse ; color black-olive, uniform,
aulcatus.
/>!>. Riblets fine; color variegated.
c. Ribets of central areas nearly obsolete ; of lateral areas
irninose, Imrin-xii.
cc. Riblets of central areas fine, distinct ; shell olive mottled
with dark, .
C. BAI:NI>H ( iray. PL 29, figs. 10,^1, 12.
Shell oval, J/y,,v.<x/f/, scarcely carinated. Black-brown, yellowish toward the ridge where each valve generally has a dark triangular spot, ami having a butt-white longitudinal stripe on each side;
Lfirdle L'lven.
areas raised, sculptured "•/'//< nlnmt (5 in-i-i/utti,-, >n,, ///o//x nulinfinfi /•//>.>-. Ccnfriif OfOtU .<>-ii/j,fii,-><l //•//// longitudinal /-/'////Vx, .v//AoA.vo///r fmnn-il tli> i1nr*nl /vWy, and some- what latticed by growth-lines. Knd valves having radiating nodulous ribs; mnfm <n tli< j,,,.^, ,•',,,,• r<ilr, very ,,<«r f In- front in<r,-(/i/i. Interior whitish ; sinus finely and rather unevenly toothed. rioi \al\c haviiiLr l."i-li;, central valves 2, (occasionally 1 on
OBZTOV-RAD8IA, I'.'l
•_' on tin- <>thrr . potterior valve L8-19 ilita Teeth l>lmit,
pertinat. narrow, SpOB
(Jirdle eovrre.1 with sliiniii-, o.nvex, minutely ,-triated scales.
n't in !><>, ( '/////.
( liitnn tarn«§t» GBAY, Spirii. 7<>ol., p. r>, t. 6, f. 22. — Sown, in M..11. Beechc}- Voj., p. HH, t. 11, f. 10; Conchol. Illustr., f. 2.— REEVE, Conch, Icon., 1. 1, f. 1 ; t. 21, f. 137.
Kntirely different from the other species of Radxia in form jind sculpture. The rihlets upon the central areas are very fine and their interspaces shallow. Occasionally a specimen occurs having some of the valves with a single slit one side.
C. GOODALLII Broderip. PL 29, fig. 9 ; pi. 28, figs. 5-8.
Shell very large, oval, moderately elevated, carinated, the side- slopes nearly straight or rather convex. Surface nearly smooth. Color blackish, olive-black or brown-black, generally showing an obscure olive-green stripe on each side of the keel.'
The lateral areas are a little raised, separated by an obtuse ridge from the central areas, and in most specimens they are son/new In it. t< miri'il IHJ roiii-i'utrlr mark* of groicth-arrest. There is no other >sru/jit- ?'/•> <>n i iflii'r c> ,it,;il nr lateral areas except an extremely minute and even granulation over the whole surface. The umbo of the posterior nifr,:* !* u ii ii.<uallij urn r f/ti' front margin.
Interior white, each valve having a pair of posterior rays and a central spot of brown. Sutural plates broad, sinus rather shallow having about 8 teeth. Anterior valve having 25-26, central valves 2-3, posterior valve 26-28 slits ; teeth stout, blunt, deeply pectin- ated ; eaves very spongy.
Girdle covered with coarse flattened-convex scales.
Length 110, breadth 70 mill.
Qafapag
Chiton i/onil,,//;; BROD., P. Z. S. 1832, p. 25.— C. godallii SOWB., Conch. 111., f. 34, 40.— C. goodalli REEVE, Conch. Icon., f. 8.—
Jiuilsin t/onilit//! Cl-JI., -V-S'.
This very large smooth species is quite unlike any other.
C. SULCATUS Sowerby. PL 28, figs. 1, 2, 3, 4.
Shell oval or oblong, moderately elevated, carinated, the side- slopes nearly straight; of a n»/j'i>rin olwe-blaehj or having the lateral areas obscurely purple-black.
EUDOXOC ill I
Lateral area- .//<//// /•"<//'"/'/// rilili»1 and grooved, the- •
terior rib of each valve broad and crenulated, the other ribs mutual, varviiiLr in number, usually split toward the outer ed^e of the shell. ( 'entral areas sculptured with numeroifs strong but smaller ribleta, \vhich near the dorsal ridge converge forward, but on the pleura they diverge strongly. End valves having strong radiating ribs, which split toward the periphery. Umbo of posterior valve prom- inent. in front of the middle.
Interior blue-green ; sutural plates broad; sinus rather deep and square, finely toothed. Anterior valve having 23-26, central valves 2-3, posterior valve 18-20 slits; teeth stout, blunt, finely and strongly pectinated. Eaves coarsely spon.iry.
Girdle covered with coarse convex scales, larger toward the periphery. Length 95, breadth 55 mill.
Qalapag
Chiton *nlr«hi8 WOOD, Gen. Conch., p. 16, t. 3, f. 1. — Sown., Conch. Illustr., f. 12.— REEVE, Conch. Icon., f. 15. — R<nl«i<i tulcata CPR., M\
This is one of the most strongly sculptured of all Chitons, and is correspondingly easy to recognize. There are usually two slits in each side insertion-plate, but the second valve occasionally h; many as four.
C. (Rnd*ia) ccerut'->«-eit« Slmttleworth, Diagn. n. Moll., no. 4, in Bern. Mittheil. 1853, p. 65. Xo description of this species has been published. It is said to be from California. Possibly founded on a Ch. ciri/H/iitn*, q. V.
Genus XIII. EXJDOXOCHITON Slmttleworth, 1853. Eudoxochiton SHUTTLW., Bern. Mittheil. hsr>3, p. C>7, type A.
unhil'i* ( lUAY. — Aoiiithn/t/rnt'ii SCCt. * * f, GRAY, P. Z. S. 1*47, p.
68, n",, ( Juildin;:.— JA<//'</' rm sect, f, GI:AY, (iuide, p. 184, 1857. — fopk ura ADS. et a/., non SHI-TTI.W.
Valves entirely exposed, smoothish, laekin-- eyes ; IDIKTO flat : the sutural plates broad and connected across the sinus ; insertion-plate- of all valves blunt, closely and deeply cleft, the median valves with 3 or 4, end valves with many >hort slits. Girdle leathery, setose. (iills extendini: the entire length of tin- :
The valves, when eroded, are seen under the len> t«. be «lnisely. evenly and regularly punctured all over. The interior is white, and
i IIM.X.H m i
<•(' a dense, porcellanuu> texture. The laciniated inMltk>n*p] cut into many short teeth, combined with the haohh mile
and continuous sut ural-plate>, an- the nio>t >t rikinir Lreiierir diar-
acten,
From A<'<inflx>}>/i urn and Mau^i-rin, irroups to which Home authors have referred the type of this ircnus, Kml<,.n,rliifoi, is sundered by the lack of eyes in the valves, the multiplicity of .-lit-, dcpres-cd inucro, etc.
I', sides the following, C/i. /inter (CLem.) Reeve may belong to this genus, but its generic characters are entirely unknown. See appendix.
I-:. eroBiua (Jray. PL 46, figs. 88-95.
Shell ohlon.ir, < /< r<itr<l, the valves well arched, and very obtusely angular on the dorsal ridge, side-slopes convex. Color uniform dark brown, a little mottled toward the beaks, and marked with scarlet there ; girdle rusty-brown.
Valves broadly A-shaped, not beaked, the lateral areas moder- ately raised, smooth except for the microscopic granulation and a few excessively indistinct radii. Central areas having indistinct growth-lines. Posterior valve (figs. 92, Q3, 94) elevated in front, the mucro flat, central ; posterior margin gently emarginate behind.
Interior porcelain-white, immaculate ; smooth and poreless. Sutural plates squared, continuous across the sinus, which is indicated by a median bay or notch. Insertion-plates having broad, blunt edges, irregularly and deeply pectinated, and having in the head- valve 30, median valves 3-4, tail- valve 24-25 short slits. Eaves very narrow, deeply grooved along the teeth and slightly spongy there.
(iirdlc(fig. 95) leathery, rust-colored, bearing short rigid bl<n-k spinelets. Length 60, breadth 35 mill. ; divergence 100°-110°. , Cnvk*' Sfntif ; Martin'* Jinii. X* »•
Acctnthqpleura >/oA///V ( ii; \v. in Dieffenbach's New Zealand, ii, p
i 1843). — Chiton (Einlu-nrl,it,m') m>/n'li* Gray, SHUTTLW.. l>orn.
Mittheil. 1*.~)3, p. 67. — Chitn,, t Ch&tcpleura) iinbili* (\\-\\\, SMITH,
Zool. Erebus and Terror, p. 4, t. 1, f. 8 (1874 >.— HuTTON, Man. N.
/. Moll., p. 115 (1880.)
This species differs from the following in its more elongated and
much more elevated contour, and in the stronger valves. The 13
I'.il TONK'IA.
seventh valve is represented in figs. 89, 90; and a square millimeter of the girdle is indicated in fig. 95.
K. nt ri MM Pilsbry, n. sp. PI. 46, figs. 96-100.
Shell oval, <l> j>, •<*.•<> <f, with convex side-slopes. Color dark brown, the girdle greenish-brown. Valves broadly A-shaped, not beaked, rounded at the ends ; the lateral areas well raised. Entire surface smooth except for a microscopic punctulation and slight growth- lines. Posterior valve (figs. 98, 99) depressed, the mucro plane, central ; posterior margin hardly marginate.
Interior white, smooth. Sutural plates continuous across the sinus which is indicated by a shallow wave or bay. Insertion- plates blunt, deeply pectinated, the anterior valve having 17, central 3, posterior 19 short slits. Eaves very narrow and grooved along the teeth.
Girdle leathery, bearing numerous short, rigid, dark brown spine- lets. Length 50, breadth 34 mill. ; divergence 135°-140°.
New Zealand.
This species is closely allied to E. nobilis, from which it differs in the proportions of the valves, depressed form, fewer slits, etc. The seventh valve is represented in figs. 96, 100. The specimen illustrated was sent me by Professor Hutton.
Genus XIV. TONICIA Gray, 1847.
Tonicia GRAY, P. Z. S. 1847, p. 65, 67; Guide Syst. Dist. Moll. B. M., p. 185 (1857), and of authors. — Probably Tonichia Gi; \ g, Synops. Contents B. M., 42d edit., p. 153, 1840 (name only.)
Generic characters. — Valves external, all having pectinated inser- tion-teeth ; sinus denticulate ; lateral areas and end valves bearing radiating rows or bands of eye-dots. Girdle leathery, naked or sparsely hairy. Gills extending the whole length of the foot. Type C. elegant Frembly.
l'> -ides the fundamental characters above recounted, the species of this genus mostly agree in having the valves >mo7»this.h, the second valve notably larger than the following five, and often differ- ently sculptured on the ridge; the sculpture is generally fine or minute, the colors much variegated or uniform black-brown, and the ••s are hardly spongy.
IVom CkcRtopleura and T<m'n-e1ln this ireim- is verv strongly differentiated by the presence of eyes, and also by the more distiix tly
i . i \ . 1 !).">
pectinated insertion-plates. Tin- .u'emis ( hiil hodiihni ha~ nmilar >iii'M»t!i valve-, !»iit the posterior valve lacks slits and teeth of
insertion,
The specie- «>f Tnu'n'in iuhahit mainly the -hores of the southern and tropical Pacific, hcin.u; found from Middle America lo < Horn, and irom tin- Philippines to Australia and New Zealand. They may l>e grouped thus:
A. Valves not immersed or separated, imbricating, section Tonicia.
1. Species of West America.
2. Species of the Wc.-t Indies.
3. Species of New /ealand, Australia, Red Sea, Philippines.
B. Valves partly separated, the girdle encroaching on them at the
sutures, section Fannettia.
Section Tonicia s. sir. I. Species of West American shores.
T. CRENULATA Sowerby. PL 45, figs. 69, 70, 71, 72.
Shell oblong-ovate, slightly more narrowed in front, moderately raised, the back carinated. Ground-color buff or slightly rose- tinged, having oblique dark olive irregular stripes, often marked on some valves with rich brown ; apices of valves pink when eroded.
The lateral areas are raised and well-defined, and except the pos- terior third or fourth, are studded closely with black eyes; the suture is prominently ami ro'iwly '-renulated, and there are some irregular radiating rows of granules on the back part of the areas, and some- times a row or two dividing the^eye tract. Central areas having a smooth keel in the middle, bounded on each ru/re by a V formed by two low divergent waves, crossed by convergent riblets ; pleura or sides sculptured with longitudinal-diverging rugte or ribs. Anterior valve high, with radiating rows of weak granules alternating with rays crowded with eyes. Tail valve with slightly posterior, elevated mucro.
Interior white, with a large red tract in each of the median valves. Slits in anterior valve s, central 1, posterior 14; teeth obtuse and short in the posterior, acute and longer in the anterior valves, sulcate
196
"in side and at edge. Sinus square, denticulate ; sutural-plates ami in>t rtiun-plates white.
Girdle leathery, thin, yellowish-green, naked.
Length 34, breadth 20 mill.
Length 50, breadth 33 mill. ; divergence 115°.
J'enrl Island, Bay of Panama (Cuming, et al) ; Mazatlan (Reigen.)
Chiton crenulatus BROD., P. Z. S. 1832, p. 27.— SOWERBY, Conch. Illustr., f. 43.— REEVE, Conch. Icon., no. 29, t'. 6, f. 39 (error for 29). "/ Tonicia" forbesii CPR., Mazatlan Catal., p. 193 (1856.)
This species is readily distinguished from the other West Amer- ican forms by the greater width of the lateral bands of eyes, the crenulated sutures, and the beautiful sculpture of the central areas. The second valve is not so prominent as in most species of Tonicia, and it is sculptured like the other intermediate valves.
T. ELEGANS Frembly. PL 41, figs. 22, 23, 24 ; pi. 42, figs. 31, 32,
33, 34, 35.
Shell elliptical-oblong, not much elevated, the dorsal ridge rounded, side-slopes straightened. Color umber-brown at the sides, becoming chestnut in the middle, delicately and peculiarly speckled and blotched and streaked with buff or buff-white.
Lateral areas hardly raised, but separated from the central areas by an obtuse diagonal ridge bearing a series of low tubercles, some- times subobsolete ; sculptural n'ith subradiating roics of small gran- ules, and showing a band of irregularly placed black eyes on the for- ward part. Central area of second valve having in the middle, a keel or a group of line ; centralareas of the other rntrrs hiring a i\«r- <Dwoth dorsal band with several longitudinal furrows on each side of if ; and at the sides there are longitudinal diverging delicate rows of granules. End valves radially subgranulate, and crowded with eye-spots subradially arranged. Mucro in front of the middle, moderately elevated.
Interior porcelain white, with a spot or " V" of red-brown under the beak of each valve. Sinus flat, distinctly but finely denticulate. Slits short, in the anterior valve 8, in the central 1, in the posterior valve '.' 1 '_' : teeth blunt, lonir and very finely, deeply pectinated out- side; slit-rays regularly puneticulate.
(lirdlr naked, leathery, of a rhe>tnut-yellow color.
Length 48, breadth '\'2 mill.; divergence 125°.
Call <tn f<> Valparaiso.
[CIA, l'»7
n ' FBXKBLY, ZooL .i<>un>. ill, p. 208, -nppl., pi. 17, f.
6. — S. >\\ r... ( 'oiich. Illuslr.. no. 75, II i.i.v i , ( ouch. Icon., t. I. f. 11). — ('. 3OWB.J Conch. IllnMr., f. 7-'), 7 \ 'young.)
The type species of T"iii<-in. The scul ptu re is well shown in fi;:. 1)%J : the color-pattern in the liirure l>ct\\ccn '2'2 and lM.
Subspecies cnii.i N-I- Fremhly. PI. 41, figs. 19, 20.
Shell rather heavier and thicker than T. rlgr/an*, with thicker girdle. G>A>r « uniform tlnrk chocolate brown, except near the beaks n'here ff» re /.< a large or sum// arm th< *hnj>r of f/ir ra/rr n-hich is /i'/hf de/irnfe/it mnff/><l irith r<'<1ai«li ; girdle dark brown, wide at the sides, narrow at the ends.
Th> tlingtinul litir /x turmounted by a wie* <>f #wnll tubercle; lateral areas showing fewer and less conspicuous eye-spots than T. el''</(iu*i and otherwise ?}/•///•/// xnumfli, flu- t/r<niul<ition being obsolete ; central areas striated on each side of a median smooth band, and more or less (variously) roughened at the sides ; second valve sub- carinate, striated in the middle. End valves radially, sparsely granulate and dotted with eyes, the umbo of the tail valve obtuse, conspicuous, elevated, a little in front of the middle.
Interior white, marked with reddish under the beaks. Sinus toothed. Sutural plates broad, especially at the outer-anterior portion . Anterior valve having 7, central valves 1, posterior valve 8 slits; t> > th r> /•'/ thick and b/tmt, strongly, closely pectinated.
Girdle leathery, naked, rather thick.
Length 38, breadth 28 mill.; divergence 130°.
Length 68, breadth 43 mill.
Valparaiso, under stones.
C. r/iit''n.«I* FREMB., Zool. Journ. iii, p. 204, suppl., pi. 17, f. 8. — REEVE, Conch. Icon., t. 3, f. 17. — Tonicia chilenxis ROCHEBRUNE, Nouv. Arch, du Mus. 1881, p. 240 (Reported from the Canaries, on the authority of specimens so labelled in the Paris Museum, but undoubtedly false.)
This form is very closely allied to T. elegans, differing mainly in the (a) dissimilar coloration, (/>) more numerous stria? on each side of the median smooth band, (c) generally obsolete granulation of the lateral areas, (d) thicker insertion-teeth, and in the thicker girdle ; a still better distinction is in the tail-valve, which in rh Mentis has a more prominent umbo, nearer the center than in < /ff/ans, and the area in front of the umbo is striated, whilst in rlei/nn* it is smooth. All
198 TONKIA.
of these differences however, do not avail to name specimen- in which various characters of eZ^an* are combined with other char- acters of cliilni.*!* ; so that while when typically developed the forms may readily be separated, it is, I believe, impossible to classify occasional synthetic specimens. I have therefore considered <-h if- a phase or variety of d> </////*.
Subspecies LINEOLATA Frembly. PL 41, figs. 25, 26, L'7.
Shell oblong, moderately raised, the ridge rather rounded. Sur- face smoothish. Ground color light fawn or fleshy, each valve close/;/ and finely lineolate with chestnut, the lines concentric to the umbones ; fifth valve marked with brown at the ridge, and often some of the other valves are marked with dark brown or are entirely of that color.
L>il<i-af areas closely, finely granulated, and having two or three rows of eyes extending down near the low, smooth diagonal. Central areas smooth except for a group of engraved grooves on each side of the smooth narron- (hr*al bawl. Second valve either smooth or hav- ing a median carina. End valves granulate toward the periphery, closely dotted with eyes in irregularly radiating rows. Urn bo of tail valve anterior, the space in front of it smooth. '
Inside white, each valve marked with reddish under the beaks. Sinus delicately denticulate. Anterior valve having 8-9, central 1, posterior valve 9-10 slits; teeth blunt, pectinated.
Girdle leathery, nude, yellowish-brown.
Length 25, breadth 15 mill.; divergence 110°.
Length 40, breadth 23 mill.
Valparaiso, Ch ill.
Chit»)i linfolatus FREMBLY, Zool. Journ. iii, p. L'i'4. suppl., pi. 17, f. 7 (Good). — SOWERBY, Conch. Illustr. (as syn. of elegant), f. 1 ">-l. — KI.KVK, Conch. Icon., t. 7, f. 34. — Tmtinu Hn<>>i/afn$ CPU. — ? Chitm, bruguieri I'ot. & Mich. Galerie, i, p. 534 (1838.)
The distinguishing characters of typical lineolatu." are the lack of larger tubercles along the diagonal rid-v. and the fine concentric line-painting. The characters of both sculpture and color-pattern however, are in some specimens inextricably united with these of T. elegan-, of which species I am therefore compelled to consider this a variety.
Many specimens show several valve- of uniform black-brown; others are blotched on many valves with the same. The species
[OTA, I'1-'
somewhat resembl< '/<i /inea/o Wood (><•<• p. H', pi. 11.
(8), lull dilli-rs sufficiently in sculpture and tli- OH <>f
black eye-pits, as well as in tin- entirely diilJ-mit insertion-p
/'. * nihles /uii'n/tifii in color-pattern, l»nt it dilfer-
entirely in having the entire central areas Inngit udinally, and the latei-il areas and end valves radially c-ostuhite.
T. i AMI..IM v (.r;iv Sowe.-l.y. PI. 41, fig. 21 ; pi. 4L>, figs. 36,
37, 38,
Shell oblong, moderately elevated, subcarinated ; the side-slopes nearly straight; surface sinoothisli. Color olive-brown, sometimes whitish, Inirl IK/ imli^lnd concentric dur/a r xtre'tk* ; rarely unicolored black-brown.
/ teral urea* hai-dlij raised, indistinctly separated from the central areas by a smooth, low or obsolete diagonal ridge. Entire surface of lateral and central areat covered with a microscopic granulation, the granules sometimes coalescing into short wrinkles in front of the diagonal at the sides. 7)o/W ridyr Imvlmj a i'cnj narrow .-•niootk band in the middle, on each *ide of whic.lt fhrre are several deeply engraved longitudinal <froov<'.-<. Second valve either smooth or having a group of striie in the middle. End valves showing numer- ous rays of eyes ; the mucro of the posterior valve prominent, in front of the middle.
Interior white, marked under the apex or suffused throughout the jugal tract with reddish. Sinus toothed. Anterior valve having 7, central 1, posterior valve 10 slits; teeth rather thin, crenulated out- side and at the edge.
Girdle leathery, nude, dark brown.
Length 54, breadth 'U mill. ; divergence 110°.
Length 48, breadth 26 mill.; divergence 110°.
. of Mut/t linn.
C.fagtigiatui GRAY, inSowB., Conchol. I llustr., t'. 11, 35. — REI Conch. Icon., f. 26.— SMITH, P. Z. S. 1881, p. 35.
ohiloensi* Sown., }>. Z. S. ls:v_>, p. 58; Conch. 111. (assyn. of elegant), f. 18*, 10, 29, 30.— RKEVK, Conch. Icon., t. 3, f. 14.
The main distinguishing characters of this species are its even fine granulation, lack of tubercles on the low diagonal ridge, few engraved grooves on each side of the smooth narrow dorsal baud, and the obscure concentrically streaked style of coloration.
200 i " M i • i A .
I do not know whether the C.clnlornsis of Sowerby belongs to this species or to C. elegans. It is represented on pi. 42, fig. 40.
T. GRANIFERA Sowerby. PL 43, figs. 44, 45.
Shell ovate, chestnut varied with white and black; dorsum elevated ; front valve radially granose ; lateral areas and posterior area of posterior valve subradiately graniferous; central areas longitudinally granose-lineate, marginal ligament smooth.
Length 25, breadth 15 mill. (&w-&.)
Conception, Chili; on Mytilus in 9 fms. (Cuming.)
C. graniferus SOWB., P. Z. S. 1832, p. 104 (Conch. 111., f. 8 ?).— KEEVE, Conch. Icon., t. 15, f. 86. — ToniciayraniferaGpR., MS.
Evidently closely allied to T. elcf/an*, having much the same sculpture.
T. GRAYI Sowerby. PI. 43, figs. 46, 47.
Shell oblong, pale, varied with brown and rufous ; anterior vnlrr, lateral areas and tail valve radially granose-striate ; anterior margins of lateral areas elevated, posterior margins [xutures] crcnulated. Central areas obliquely longitudinally granulose-striate ; third to ft i-i-nth valres longitudinally bixulcate in the middle. Marginal ligament smooth. Length 30, breadth 17 \ mill. (&»/•/>.)
Island of St. Lawrence, Bay of Callao, Peru, on shells in 17 fms. (Cuming.)
Chiton f/raifii SOWB., P. Z. S. 1832, p. 57 ; Conch. Illustr. f. 8.— REEVE, Conch. Icon., t. 17, f. 105. — Tonicia grayi CPR., MS.
This form is evidently closely allied to T. elegan*, etc. The italics of Sowerby's description translated above are my own.
Carpenter thus describes the type specimens : Jugular areas with deep grooves on each side of the central smooth rib, but both grooves and rib are evanescent on the second valve. Central areas with a second set of granules parallel to the diagonal and more or less con- tinued into faint riblets, somewhat diverging from the more prom- inent apices. Lateral areas with a very decided row of rugose granulations along the diagonal, inside of which is a smooth space crowded with metallic dots [eyes] ; then two or more rows of very rough irregular granules, ending in sharply crenate sutures. End valves with about eleven obsolete riblets, irregularly Lrranosc, with rows of metallic dots between each. Mucro in front of the middle, swolk-n, but the slope behind it Anterior valve having 8
central I, po.Mrrior valve II slils; treth v«-rv .-harp, !"•<•! inat«-d Sinus Hat moderately deep and hn»ad, \\ith up to Hi teeth.
Lengtli 80, hreadth 17 mill.; divei
T, MKMA Sowerl.v. IM. II. ftgi, 28, I".), 30.
Shell oval-oblong. smooth, sulicarinated ; valve- ncarlv sul.n»trate ; lateral areas inconspicuous; maririn ['_rmlle] smooth.
Length 26, breadth 1 L'.1. mill. \o,r/,.)
The smooth, narrow, .-lightly aiiLrulated species above de-rrib« of a blackish-brown color; the lateral areas an- not distinctly marked except l>y rays ot'liirhtcr color in some specimen- on them, and on the terminal valve>. (.sVw/>.)
F'tlL-tnnd I*. (Sowb.) ; Ora),<f 7/./rW (U. S. Ex. Exped.)
Chit nn nti-nttt Sowu. in Charlesworth's Magazine of Nat. Hi-t. 1840, p. 294 ; Conch. Illustr., f. 57, 58.— REEVE, Conch. Icon., t. 1 7, f. 103.— GOULD, U. S. Kxpl. Kxped., p. 329, f. 415.— 7 o// //•/,/ ntrata H. ct A. ADS., Gen. Kec. Moll, i, p. 474. — ROCHKHIIUNK, I'olyplac. Cap Horn, p. 138.— T7. bcetica CPR., 3/N. <,lim.
I have not seen this species. Carpenter writes: Mucro more or less elevated, tumid behind. Inside having 8 slits in the anterior, 1 in the middle and 12 in the posterior valve; teeth acute, outside and at the edge silicate, scarcely pectinated; sinus moderate, Hat, with i:>-20 denticle-.
Hutton reports this species from Macquarie Island, X. /., but says: " Our species agrees very well with Reeve's figure, but not with hi.s description. The anterior terminal area is distantly radiately ribbed, and the lateral areas are sometimes defined by a single rib. The umbone of the posterior valve is more posterior than in the drawing, and the valves are of a uniform hrown color. The mantle is of the same color as the valves." These characters seem to me to indicate a distinct species, which may he called /'//
T. SWAINSONI Sowerby. PI. 43, figs. 41, 42. 43,
Shell oval, moderately or decidedly elevated, somewhat earinated. the side-slopes nearly straight. < I round-color li^ht pinki>h-l>uH'. /minted all over with n mult if ml- r rrtl-hroivn linen, <
t» the beaks; often havinir some valves striped at or on each side of the ridire, or more or le>s completely covered with dark n-d-l»ro\\n.
Lateral areas little raised, xo////^,>'</ "•/'/// ufn,,,t s
202 TONICIA.
the riblets sometimes broken into rows of distinct granule.*. Central areas lonr/iti«lin<t//i/ codnlnte except for a narrow, smooth dorsal band on the latter 6 valves. End valves radially ribbed, with rows of eyes in the intervals. Umbo of tail valve anterior, elevated.
Interior white, some or all of the valves having a small reddish spot under the apices. Sinus narrow, denticulate. Anterior valve having 8, central 1, posterior valve 10-12 slits; teeth pectinated.
Girdle yellow or brown, leathery, thin.
Length 34, breadth 20 mill.; divergence 100°-110°.
Callao, Peru.
WMontt SOWB., P. Z. S. 1832, p. 27 ; Conch. Illustr., f. 5.— REEVE, Conch. Icon., t. 7, f. 38. — Lophyru* swainsonii TAP.-CAN. Viag. Magenta, p. 75.
This species is well differentiated from forms of the elegans group, by the longitudinal ribbing of the entire central areas. The ribs vary much in prominence, however, and in many individuals the riblets of the lateral areas are broken into granules. The color- pattern is similar to that of T. lineolata, but finer.
T. RUBRIDENS Pilsbry, n. sp. PL 44, figs. 65, 66, 67.
Shell oblong, elevated, the dorsal ridge roundly angular, side- slopes straight. Surface smooth. Tawny-brown, sometimes uni- colored, but generally having dotted light rays on lateral areas and end valves, and a dark dorsal band. A light fawn color sometimes predominates over the dark.
Valves rounded at the front corners, moderately beaked ; sutures not crenulated.
Lateral areas not perceptibly raised (except on the second valve), sculptured with minute, i/i'iinu/r* npnwhj nml irn </"/"/•/'/ .*nitfi /•«/, varying much in number; and along the forward part there is MM series of *mall black eye-dots, becoming an irregularly double series on the lower half of the slope. End valves weakly Lrranulose and having radiating rows of eyes. ( '< at ml an </.« ' /////•< /// *uinnfh e.rr,/,! fur growth-line*, huviny no ijrnoi'i* (i/o/iij fftt- tli,r*nl ri<l<j> . Beak of tail-valve obtuse, behhul il< miililfc.
Inf< n'or of a jie'-u/inr r»l-/>roirn color, the callus of each valve- whitish. Siittirii/'ii/nfi.« //////, )'til-l»rnirn. Sinus delicately dentic- ulate. the area behind it, extending to the beak, transversely wrinkled. Slit< in anterior valve 8, central valves 1 . posterior valve
'I .
roinci \.
teeth finely crenulated oiilsidr ami at ed'je, rather thin, and colored ivd. A- in other -prrirs liavini: a po-h-rior mncro, the tail- valve teeth art- directed forward.
< iirdlr yellowish, leathery, nude and smooth.
Length L'*, luvadth 1 :» mill.; divergence 108°.
Callao ; and Chili (U. S. 1
This species differs from all of the T. vtcgans group in lacking sculpture upon the central areas and engraved grooves along tin- dorsal ridge; and from other species of Toniria in the red sutural- platcs. teeth, etc. The blunt inucro is posterior, and the teeth in the tail-valve are directed forward. The posterior margin of the tail valve is broadly waved upward in the middle, as in Eudoxochiton.
T. HORNIANA Rochebrune. PL 43, figs. 50, 51.
Shell ovate-elliptical, carinated, rufous, marbled with buff and roseate ; anterior valve radially costate, posterior valve small ; inter- mediate valves having the central areas minutely concentrically striated; lateral areas multi-sulcate and ornamented with two lines of dots. Marginal ligament dull roseate.
Length 19, breadth 14 mill. (Eochebr.')
Orange Bay, Patagonia.
T. horniana ROCHEBR., Polyplac. Cap Horn, p. 139, t. 9. f. 7.
T. M ARTIELI Rochebrune. PL 43, figs. 48, 49.
Shell ovate-elongate, strongly carinated, the ends of the valves curved backward, brown-rose, anterior valve radially strongly costate ; posterior valve small ; intermediate valves having the central areas transversely lineated, lines denticulate; lateral areas granulated and margined by asquamate hand. Marginal ligament violaceous-rufescent. Length 21, breadth 14 mill.
Strait* <>f Miiyltitn.
T.martieli ROCIIKHK., Polyplac. Cap Horn, p. i:J!», t. 9, f. 8 (1889.)
T. LI.HKUNI Rochebrune. PL 43, figs. 52, 53.
Shell ovate-elliptical, carinated, shining, violaceous or greenish- roseate. End valves radially most minutely striated; intermediate valves having the lateral areas covered with tubercles ; the central areas concentrically silicate, the sulci wavy; marginal ligament narrow, leathery, whitish- violaceous.
Length 29, breadth 12 mill. (AV//e6r.)
Punta Arenas, 0 ran y /: . >';. /•/' .1A/;// //»//».
•J'»J -I CIA.
Touiria lebnnii ROCH., Bull. Soc. Philomath. Paris, 1883-'84, p. 35 ; Polyplac. Cap Horn, p. 138, t. 9, f. 6.
T. FONTAINKI Rochebrune. Unfigttred.
Shell ovate, broad, subcarinated, gray, with brown spots. Ante- rior valve, lateral areas of intermediate valves, and posterior part of posterior valve very delicately striatulate and sparsely covered with conic tubercles ; central areas sculptured with beaded longitudinal waved lines. Marginal ligament rather wide, leathery, rufous.
Length 11, breadth 9 mill. (Rochebr.}
Chili (M. Fontaine) ; Paris Museum.
Tonicia fontainei ROCHEBR., Bull. Soc. Philom. de Paris, 1881- 1882, p. 193.
The foregoing species are not defined with sufficient exactness to insure their indentification, Rochebrune being a century behind the times in descriptive zoology.
T. ARGYROSTICTA Philippi. Unfigured.
Girdle smooth. Valves smooth, subcarinated ; lateral areas hav- ing a single series of distinct silvery impressed dots.
Length 4J, breadth 3 lines.
This small species is sufficiently distinguished by the peculiar impressed silvery -shining points, which remind one of the similar marking on some Carabidse. On both end valves they stand in several concentric rows. The coloring varies ; the brown-red color predominating; in one example there are whitish flecks and trans- verse stripes, in another longitudinal stripes. (Phil.')
Strait* <>f Muyellun.
Chiton argyrostictus PHIL., Archiv fur Naturg. 1845, p. 59.
T /.SCHAUI Pfeffer. PI. 40, fig. 12.
The animal is much elongated, the breadth hardly one-half the length. The inner region of the girdle is covered with very minute granules, hardly visible under a strong lens, arranged in not entirely regular oblique series, and separated by about their own dimensions. Under a low-power lens the girdle appears. quite naked. Toward the margin these granules grow into transparent, short spines. The 28 branchiu.' roach the entire length of the foot.
The valves are quite shining, and sculptured with close growth- stria? ; otherwise they appear smooth under a \\vak power of the lens; under strong magnification a fine granulation is \i>il>lr. The median valves have only a low angle separatini: central and lateral
01 v.
arras; the growth wrinkles, which mi the lateral U and
prominent, are Weaker OD the central areas, the posterior part of which appear sculptureless. The iimho seem.- to \v produced hack- ward [heakedj in young shells, hut in this specimen it is so upon the I'd valve only. The dorsal ridge is bluntly angular. The head valve is long compared with its hreadth, the length of the front slope equalling tliat of each of the posterior margins ; it shows weak concentric sculpturing of stria?. Tlie tail-valve is small and narrow, not much more than two-thirds as broad as the head valve, and also notably shorter; its forward area is not shining; the posterior segment is shining and sculptured like the head valve.
The lateral areas and the outer anterior parts of the central areas are yellowish-red with red marbling. The central area shows on its middle part, a group of beautiful chocolate-brown and violet- white stria?, radially diverging from the umbo. On the anterior median valves are seen also a few clear brown streaks on the outer part of the central areas.
The single specimen before me is fastened on pasteboard, and measures 13'5 by 6 mill.; the broadest valve is 5 mill., so that the girdle is but *5 mill., wide. The third median valve of this specimen is abnormal in being pure white.
South Georgia.
Chiton zschaui PFFR. in Moll. Siid-Georgien, Jahrb. Hamb. Wissensch. Anstalten iii, p. 105, t. 3, f. 2 (1886.)
This is placed in Tonicia with much doubt, for the presence of eyes is not noted in Pfeffer's description, above.
T. TEHUELCHUS d'Orbigny. PI. 40, figs. 13, 14, 15.
Shell oblong, elevated, strongly carinated ; brown with two white longitudinal zones ; head-valve and lateral areas radially sulcate- bifurcate; central areas longitudinally punctate-silicate.
Length 27 mill. (Orb.)
Jj<n/ i»i Sun lilni*, Patagonia*
Chiton tehnelchus ORB., Voy. dans I'Amer. Merid., p. 488, t. i '»."». f. 7-13.
The sculpture reminds one of Chcetopleura inlrn Wood. The generic position is not certain.
2. We*t I it'll' in species. T. SCHKAMMI Shuttleworth. PI. 4:>, figs. r>4, 55, 56.
Shell oblong, moderately elevated, roundly angular. Surface polished. Qround-eolor l>uj)\ mnitlt<l, sp^-klcd <>r sometime*
206 i CIA.
with bright rtddith-brown. Valves strongly beaked, the umbo of the far to the posterior (fig. 54). Central area* smooth throughout; lab ml areas separated from the central by a prom- inent, rounded, curved diagonal rib, and #mo<»th except for a broad band of black eye dots, variously arranged, on the forward half; suture* feebly or obsoUfaly crenulated. Head-valve smooth except for 8-10 broad rays of eye-spots.
Interior white, stained with crimson along the jugal tract. Sinus obsoletely denticulate. Anterior valve having 9-10, central valves 1, posterior valve 14 slits; teeth deeply and regularly pectinated on outer face and edge. Posterior border of each valve in flexed and maculated with reddish.
Girdle leathery, tawny, flesh-colored.
Guadalupe ; Florida Keys ; Bermuda,
Chiton (Tonicia) Mchrammi SHUTTLW., Journ. de Conchyl. 1856, p. 171, t. 6, f. 9. — T. schrammi HEILPRIN, The Bermuda Is., p. 176. BALL, Catal. Moll. S. E. U. S., p. 174.
This form differs markedly from those of Western South Amer- ica in the non-sculptured central areas, prominent diagonal rib (like that of T. cremilata), and broad bands of eye-spots. The umbo of the tail-valve is far backward, and in most specimens the posterior margin of the same valve is distinctly emarginate in the middle, the teeth being much shorter there and irregular. In this it resembles Eudoxochiton. The diagonal rib is more prominent, and the eyes far more numerous than in T. rubridens. The nearest ally of schrammi is the very differently sculptured T. crenulatn.*.
3. Specie* of Australia, New Zealand, Philijui'me*, etc., etc.
T. 8UEZEN8I8 Reeve. PI. 40, figs. 16, 17.
Shell oblong ovate, valves very closely concentrically wrinkled at the sides, with oblique wrinkles toward the middle; yellowish, delicately stained with pale scarlet and green ; ligament horny. (Reeve.)
f of Suez.
C. suezensis K i i \ i , Touch. Icon., t. 20, f. l.".-4 (May, 1847 ,— !>.-] i. Moll. Mar Ross., . p. 235.— COOK i:, Ann. Ma-. N. H. 1386, j». 276.— ' S \vh.sx. | ),.>cr. Aegypte, t. 3, f. 4. — Tonieia f suezensis (Vi:.. MS.
Carpenter writes: Mucro subposterior-median, rectangularly elevated. Interior: anterior valve having 8, central 1, posterior valve 13 slits; posterior teeth shorter, bending forward, anterior
[( I \.
sharp. i , v« -ry deeply pectinated. I ... tdl -inns
minutely denticulated. This species :nnl the following, with trniH'iitn. are intermediate between Tnnirin and .\r,it,ffi»/>/>'ii,-'i ; hut they a-Tee with this ireiius in the porcellanoiis texture, deep slits, angular denticulated -inus and pect inated teeth. Tin- .-li-ht la: lion of the girdle appears to l>e a secondary character.
T. NIGBOFUN4 r\i \ ( 'arpenter. Unfigured.
sholl small, rather elongated, elegantly clouded olivaceous and l>ro\vn ; moderate] v arched, the dorsal ridge obtuse. Lateral areas moderately defined, ornamented with radiating and longitudinal wrinkles irregularly decussating, with black dots scattered between them. Central areas having subparallel, subdecussating, scarcely regular ribs, obsolete at the jugum. Mucro posterior, elevated.
Interior having 8-10 slits in the anterior, 1 in the central, 12-14 in the posterior valve ; teeth in the posterior valve solid, sloping, short ; sinus broad, denticulate. Girdle copiously clothed with hair- like scales. Length 12, breadth 6'2, alt. 1-7 mill. (Qpr.)
Tahiti. (Pease.)
Acanthopleura nigropunctata CPU., P. Z. S. 1865, p. 511. — PEASE, Amer. Journ. Conch, vii, p. 194. — Tonicia nigropunctata CPR., J/\
This species is most closely allied to T. suezensis, but the latter has the valves more beaked and curved, and the central rugae per- pendicular to the diagonal lines, while in this they are nearly parallel to the dorsal ridge.
T. FORTILIRATA Reeve. PI. 40, figs. 3, 4 (enlarged.)
Shell ovate ; valves somewhat beaked in the middle ; posterior valve umbonated, blunt ; lateral areas rather concave, granulated anteriorly ; central areas strongly arcuately ridged. Yellowish variegated with green, stained with red in the middle. Ligament horny. (Reeve.)
Rait if* f-^'ind, Torres Sts. (Ince) ; Port Darwin, 8-10 fms. sand and mud ( '( !oppioger.)
Chiton fortilinihi* KVK., Conch. Icon., t. 18, f. 112.— C. (ZWcm) fortiliratus SMITH, Zool, ' Alert ' p. 84.
( 'arpenter writes of the type: Anterior valve having «>, central valves 1, posterior valve 13 slits; teeth short, numerous, very sharply pectinate: short at the hinder end but gradually becoming a little longer. Kaves short, slightly rugose, not spongy ; sinus with about 20 teeth, rather broad, flat. Interior whitish. Outside ashy
2<»S TONICIA.
>usly pencilled and marked with olivaceous; beaks small, con- spicuous. Jugal area very small, smooth in front. Central areas with :il»out 20 smooth riblets, curving toward the middle on the median part of the areas, and toward the outside of the areas radiat- ing outward. Lateral areas scarcely raised, having faint rows of granules; at diagonal rib and at sutures having slight elongated granules toward the sutural ribs and rows of metallic dots next the diagonal ribs. Anterior valves with granules and irregular rows of metallic dots alternating; crenate at suture. Posterior valve with median, raised, swollen mucro ; posterior slope straight. Length 28, breadth 18 mill.
The single specimen collected by Coppinger is thus described by Smith : It is of a greyish-pink color, copiously blotched with black along the sides of some of the valves. The headplate •* -:•:- insertion edge is much thickened, coarsely striated externally, and is divided by 8 short narrow slits. The exterior surface is coarsely subsquamately granulated throughout, and exhibits numerous black raised dots, disposed in rather irregular radiating series. The second valve is long in comparison with those which follow, feebly peaked behind ; the fourth, fifth and sixth plates are about equal in size and a trifle broader than the third and seventh. All the inter- mediate valves are very coarsely ridged and sulcated on the central areas, and coarsely grained and minutely black-dotted on the sides (lateral areas). The ridges are flat-topped, clean-cut, nearly smooth, attenuated posteriorly, wavy, converge on each side toward the front, and the intervening grooves are feebly punctate. All have the hinder margin nearly straight and but feebly pointed at the poste- rior apex. * •* •* The posterior valve is strong and thick, obtusely mucronated in the center, very coarsely striated and serrated upon the thickened insertion-margin, which is subdivided by about 10 dis- tinct notches. The interior of the valve is liirht livid bluish, with a reddish stain along the middle of all, with the exception of the last. The mantle, as described by Reeve, is simply "horny." Length, without girdle, 18, diam., of fifth valve 9 mill. Reeve's type is a larger >peeimen. lieinir -4 mill, long, 13 wide, without girdle.
I - \i:ri.vn:i:i Aiiiras. IM. 40, ficr. 7.
Shell ovate, elevately convex. carinat< d. :i>hy white, ornamented at the hinder edges of the valves with pale spots, the spaces between which are very dark olive, melting into ei»nfu>rd hands of a paler hue which extend nearly across the valves; valves rostrate, undul-
K'MCIA.
ately concentrically -iil>inil>ricately sculptured throughout: the lateral aiva- not raised luit separated from tin- dorsal areas by an elevated ril>. Posterior valve strongly gibbous, the umbo almost terminal; mantle margin hrown. Length 9 lines. (Angas.)
Port Jackson, Au-<trnli<i.
nf.ri AN<.., I*. X. S. 1867, p. 116, 223, t. 13, f. 30.
Carpenter gives the following descriptive notes :
One specimen without anterior valve. The specimen as it stands measures length 17, breadth 15 mill. ; but measuring the valves only and allowing for the missing anterior valve it would be length 16, breadth 10 mill. Shell oval, moderately elevated, the dorsal ridge acute; olive clouded with dark, tessellated with light so as to appear toothed at the sutures. Mucro central, swelling, elevated, the pos- terior slope convex. Jugal area a rather narrow, nearly smooth dorsal line. Central areas with about 16 finely, rugosely sculptured, nearly concentric, but faint, grooves on the otherwise smooth surface. Lateral areas slightly raised by the curved diagonal ; having lines of stumpy granules and concentrically rugosely grooved in continua- tion of the sculpture of the central areas, obsolete at sutures. Pos- terior valve concentrically grooved like the rest, all around. Girdle nearly smooth, very slightly lanugate. Posterior valve with 11 slits ; teeth rather sharp, grooved outside ; eaves very small. Sinus broad, flat, deep, having about 17 very slight teeth.
This species is a transition toward Acanthopleura in the thrown- forward teeth, but girdle and sinus are more Tonicioid. (Q>r.)
T. LAMELLOSA Quoy & Gaimard. PI. 40, figs. 8, 9, 10, 11.
Shell small, oval-elongate, subelevated, carinated ; valves trans- versely scaly-striated, variegated with gray or ferruginous ; girdle thick, smooth, reddish marked with radiating brown lines. Anterior valve having 10 crenulated teeth, posterior 9, and a much project- ing tuberosity. Color of valves grayish-yellow, varied with brown, red or greenish. Girdle usually yellow. (Q. & (•?.)
Length 15, breadth about 8, alt. 5 lines.
Tnnfja Tabu.
Chiton lamellosw Q. & G., Zool. Astrol. iii, p. 386, t. 74, f. 29-32.
This species has the mucro more posterior than any of the preced- ing species. 14
TONK'IA.
T. CONFOSSA Gould. PI. 57, figs. 33-36.
Shell oblong, solid, elevated, the side-slopes straight, dorsal ridge <-;uinated. Ashy white, delicately maculated with various shades of reddi-h and purple-brown, the darker color irregularly tessellating the posterior margin of each valve.
The median valves are moderately beaked ; the lateral areas a little raised, and posteriorly and on the diagonal are very peculia rly sculptured with transverse narrow le<l<je#y like the edges of xhinab-* imbricating from the outer margin of the valve upward ; median por- tion of the lateral areas smooth, dotted in a widening band with eyes. Central areas peculiarly marked with sparsely scattered subtriangular in some places arranged in irregular transverse rows. Anterior valve having radiating series of ^-shaped imbricating large scales, alternating with narrow bands sparsely dotted with eyes. Posterior valve hiring the prominent mncro near the posterior end, the slope behind it vertical, in front of it horizontal ; a narrow band of eye dots is behind each diagonal, and they are very sparsely scattered over the rest of the posterior area.
Interior white. Sutural plates separated by a moderate sinus, which is delicately denticulate except in the second valve. Anterior valve having 8, median 1, posterior 15 slits; the teeth sharply and deeply pectinated outside; posterior teeth somewhat directed for- ward, deeply pectinated, the slits rather shallow. Eaves narrow, slightly projecting downward near the teeth, and very narrowly grooved just outside of them.
Girdle blackish-brown, rather fleshy, nude.
Length about 18, breadth 11 mill.; divergence 120°,
Fiji Is.
Chiton confossus GOULD, Proc. Bost. Soc. Nat. Hist, ii, p. 143 (July, 1846) ; Expedition Shells, p. 5 ; Wilkes' Expl. Exped. Moll., p. oL'7, atlas f. 434, a, b, Otia Conchologica, p. 5. — Chiton (Lucia) confostus GOULD, Otia, p. 242. — Lucia confossa GOULD, Proc. Bost. Soc. viii, p. 283. — L»<-i/ina confossa DAI.I..
The prominent, posterior mucro, and the peculiar sculpture render this species easily identified. It belongs to that numerous East Indian group (see p. 206) characterized by a rather swollen posterior or post-median mucro, forward-tending posterior teeth, and by the generally punctured grooves of the suriace-culptmv ; but in this species the character of the sculpture is unique in the total obsolescence of concentric or forwardly converging riblets on the
[CIA, :2 1 I
mitral aiva<, and tin- development of angular sejitten-d pil
The tail-valve is emarginate behind a- in Kmlnj-or/iiinn and many
Toniei:i<. Kiur. •'!•"• represents the Interior of the SeOOnd valve, which is longer than the following valves, as usual in Tnn'n'ln.
It i- imt rasv to 166 ln»\v (Jonhl could write so confidently of the plurality of side slits, unless he examined the figures in the Ivxploj- in.ir Kxpedition Atlas instead of the specimen itself; but this i doubt the case. The artist oi' the expedition in d rawing these figures, mistook the deep pectination for veritable slits, and represented them as such. In the figured specimen, now before me, the girdle in dry- ing has parted from the eaves, partially exposing the deeply pectin- ated insertion-plates, as represented in figures 434 b of the Atlas ; but as I have above explained, the deeper grooves of the pectination have been very erroneously drawn in those figures as slits. The fact is that although the grooves are strong and deep on the outside of the plates, they scarcely crenulate the summits of the teeth, and are as different as possible from true slits.
The genus or subgenus Lucia (Lucilina) has therefore no stand- ing whatever, but becomes a synonym of Tonicia. This species can- not be included in Acantkopleura on account of the different arrange- ment of the eyes, the smooth girdle (which in this species seems to be more fleshy than leathery), and the denticulate sinus.
T. PICTA Reeve. PL 40, figs. 5, 6.
Shell ovate ; valves, the posterior terminal truncated, ornamented with short, sharply undulated wrinkles, the interstices between which are punctured ; anterior edge, of the lateral areas keeled ; pinkish- wliite, showily painted with green and scarlet spots. Ligament horny, transparent. (Rve.)
Raine's Island, Torres Sts. (Capt. Ince.)
C. pictus REEVE, Conch. Icon., t. 15, f. 79 (March, 1847.) Allied to C. truucatus, distinguished by its sculpture and flattened growth. (Rve.)
T. TRUNCATA Sowerby. PL 40, figs. 1, '2.
Shell oblong, rather elevated, the dorsal ridge rounded ; ashy- flesh colored, variegated with darker or olivaceous, dotted with black, and sometimes rose-tinted along the dorsal i i
Valves much rounded and separated at the ends ; entire surface grauulose ; central areas engraved with superficial waved grooves ;
212 TONICIA-I ANNKTTIA.
lateral areas hardly elevated, irregularly rugulose. Mucro behind the middle, much elevated.
Insidr having in slits in the anterior, 1 in the median, 14 in the posterior valve; teeth of the tail valve directed forward ; those of the central and front valves sharper, deeply serrated outside and at the edge. Sinus moderate, deep, flat, with about 20 delicate denti- cles. Length 38, breadth 20 mill.
Siquijor, Philipp ines.
Chiton tnincatus SOWB., P. Z. S. 1841, p. 61.— REEVE, Conch. Icon., 1. 16, f. 93. — Acanthopleiira ? truncata GRAY, P. Z. S. 1847, p. 68. — Tonic'ci truncata ADS., Genera i, p. 474, and of SHUTTLW. and CPR.
Resembles Tonicia (Fannettia) disjuncta in the partial separation of the valves at the sutures. The tail-valve is formed much like that of Acanthopleura.
A variety with nearly smooth valves has been noted from Samar. Carpenter described in MS. a Cumingian specimen as T. jugosulcata,. said to be from Tasmania, but he later regarded it as a form of trinimta. The locality Tasmania is very doubtful.
Section Fannettia Dall, 1878.
Tonicia § * * , GRAY, P. Z. S. 1847, p. G7.—Fannyia GRAY Guide Moll. B. M., p. 185 (1856).— Fannia CPR., not Fannia Rob- ineau Desvoidy, 1830. — Fannettia DALL, Proc. U. S. Nat. Mus. 1882, p. 284, 287, 289.
This section is like Tonicia in all respects except that the mucro is flattened, the teeth of insertion are, somewhat longer, and the broad girdle encroaches upon the valves at the sutures, nearly separating them.
T. DISJUNCTA Frembly. PI. 39, figs. 35-41.
Shell oblong-ovate, reddish-brown, with green and straw-colored markings; valves smooth, glossy, the anterior margins of the dorsal valves are arcuate, the beak only of the next forward valve cover- ing them, </i\ -ini: the valves a disjointed appearance. Lateral areas low; mucro of tail valve median, subplanate.
Inside white; anterior valve having 9, central 1, posterior valve 9 short slits ; teeth elongated and strongly grooved outside ; delicately serrated at the acute margins; teeth of tail valve short and solid behind, el<>ni_r:itnl in front. p]aves narrow; sinus dentic- ulate.
N i ii' .1-1.1.1 i: \.
Girdle smooth, broad, ^xteDding lictwrni tin- valv<-s, and \vln-n
living marldrd with vivid n-d, ^ivm and blur. Length 62, breadth .",7 mill.
Valparaiso, f'lu'fi.
Chiton <{(.</ n nrt u.^ Kiir.Mr.i.Y, /<><>]. .Journ. iii, p. 203, suppl. pi. 17, f. 5 (hrtwrrii Oct., 182<> and May, 1827).— I: < onch. Icon. t.
4, f. 21.— GOULD, U. S. Kxpl. 'Kxped., Moll, and Sh., p. 329.— Fannyia •' dispuncta " [err. typog.] GRAY, Guide, p. 185. — Fannia iliyunrta Cl'R., MS.
" The transitions between this species and the normal Tonicice are so gradual, that it scarcely seems entitled to generic rank. The valves are not much more covered than in T. truncata; but instead of the lateral sinuses being angular, they are gradually rounded, and extended to the apices of the valves. The principal peculiarity is in the flattening of the mucro ; the creature, having devoted itself to lateral expansion, had no need to push its tail up into a hump. The slits are as short as if the valves were fully exposed, only extend- ing up one-third of the teeth in the anterior valve and one-half in the others. Inside, however, the gums rise to the level of the slits, so that, when seen from within, the shell appears perfectly normal. According to Gould, E. E. Moll, p. 329, the girdle is "distinctly cleft " behind. This is duly represented in the Atlas, f. 417. I have not, however, been able to trace it in either of the specimens examined. That in Dr. Gould's own cabinet, although in good con- dition, shows no trace of it. Neither Frembly nor Gray allude to it.
Genus XV. ACANTHOPLEURA Guilding.
Acanthopleura GUILD., Zool. Journ. v, p. 28 (in part), -f Core- phium GRAY, Maugeria GRAY, Francisia CPR.
Valves exposed, beaked, generally lusterless or eroded ; provided with eyes on the forward part of the lateral areas and the end valves ; mucro posterior ; interior colored, the tegmentum broadly inflexed at the posterior margin of each valve. Insertion -plates all conspicuously pectinated outside, and directed forward. Girdle thick, covered with small or large calcareous spines.
History of the name Acanthopleura. — Under Acanthopleura, Guilding defined seven sections, naming a representative of each. His scheme is here reproduced, the modern equivalents of the species named being added in brackets:
214 ACANTHOPLEURA.
* Zona spinosa. Chiton yuwsua Sow., Gen. f. 1.
\=Acantkopleura spinosa Brug.] * * Zona spinulosa. Ch. tarmvokaefa Gray, Spicil.
[==Plaxiphora.] * * * Zona granulosa. Ch. asellus Lowe, Zool. Journ.
[=Lep\doplewru*i p. 13.] * * * * Zona rugoso-granulosa. Ch. asselloides Lowe. [=
Trachydermon albus L., p. 70.] ***** Zona crinita. Ch. crinitus Wood, Index. \=Acan-
thochites.~] ****** Zona villosa. Ch. peruvianus Frembly. \=Ch«fn-
jileura, p. 28.]
******* Zona farinosa. Ch. cinereus Lowe. \==Traehyder- mon, p. 68.]
As neither of these sections were selected by Guilding as the typical group, we are obliged to select a type for ourselves ; and of course the choice must be limited to the species actually enumerated by name in Guild ing's *cheme of sections. We must first exclude such species as are already provided with generic names ; and glancing down the list we therefore, eliminate section * * *, which falls into Risso's earlier genus Lepidopleurus, and section *****, which belongs to Acanthochites Risso. Of the five sections remaining, * * was separated by Gray in 1847 under the name Plaxiphora. Section ****** was denominated Chcetopleura by Shuttleworth in 1853 ; and for the species included in sections * * * * and * * * * * * *, Carpenter established the genus Trachydermon, in 1863. These successive dismemberments have left only ihefirtft tectitm of Guild- ing's arrangement, to represent the original genus ; and Chiton spinoms, therefore, becomes the type of Acanthopleura Guilding.
Unfortunately for science, few authors have arrived at this result; but the fact that it rests upon principles "t nomenclature from which there is no appeal, will, it is believed, be evident to all.
Since Guilding's publication of the name, it has been considered by the following systematists :
1840. SWAINSON defines the genus (which he calls " Canth«}>]< <Miild."), and names "(7. spinom*, Sow. Gen., f. 1" as the representative or type. No other species is mentioned.
1847. GRAY defines the genus, including in it sections as follow.* :
* A.periiri'in'i I, in., bicolor Ad., hennnli (Jray, <"//-"/m Sowb. [==Chatopkurci -f-
* * This divide into three siil>MTti«m~ :
f A. nnbi/iit (I ray. [—EudoXOCMtOH.']
ft A.pioia Sow., *i>in ii/ci-'i S>\v., MMfiti Gray, j^xosa Brug.,
/;/•/ S I'jti'ifirn ( I ray. [ ,!/'/"'/'/•/'/.]
ftt A. f git/"* (imel. [=Dwi0p four] ; A. f trum-titn. [=2W- toio.]
Neitlicr of these sections is selected by Gray as typical ; but in his " List of the Genera of Recent Mollusca, their synonyma and types " P. Z. 8. 1847, he gives on p. 168, no. 413, " Acanthopkura (iuild. 1835; Gray, 1847. Canthapleura Swains., 1840. Ch. 8pin< It appears then that not only Swainson, but Gray himself selects C. yi nn*u * as the type species.
1853. SHUTTI, i:\voiiTir, in a most scholarly essay, divided Gray's Acautho/ilenra of 1847 into three sections: Chcetopleura [equivalent to Gray's sect. * and part of f t t> and including C. rugosu* (Gray) Sowb., per n vi<nuis Lm., gigas Chem.] ; Eudoxochiton [for C. nobilis Gray] ; and Acanthopleura, restricted, [equal to Gray's Acantho- j>[> ura sect, f t plus Corephium, with some other miscellaneous species].
In 1856, GRAY again made a cruel onslaught upon the genus; and here he restricts Acanthopleura to the sect. * of his 1847 arrangement, ignoring the fact that Shuttleworth had meantime given a new name, Chceto})leura, to that section, and apparently forgetting that he had himself said in a former paper that C. spinosus was the type of Acanthopleura ! In the same paper, he proposes a new genus, Minnjrriit, for the following species, which he arranges in two sections: f> M- nobilis {_= Eudoxochiton Shuttl. 1853]. ft* ^[. /n'rc'i Sow., ,*/>! a iyera Sow., oiven.ii, a/nnosa Sow., brevispinota Sow., magnified Sow., C. 111., f. 52. He also retains his genus Core- phium for C echinatum Sow., 111., f. 47.
1858. Messrs Adams, in their Genera, reunite Acanthopleura and Coreplu'inn, with a choice assortment of other forms, under the genus " Chiton /,in turns." As the status of this generic name has been fully discussed by me on p. lf)0, comment here would be super- fluous.
1873-1882. Carpenter, in his MS. arrangement of Chiton* (an abstract of which was published by Dall, Proc. U. S. Nat. Mus. 1881, p. 284, 287), proposes to retain the name Acantkoplevra for the group of Ch. piceus; Corephium for C. echinatus ; and T7/'/ Cpr., ?ioi'., for Ch. spinosus. This arrangement is not acceptable
216 ACANTHOPLEURA.
because (1) Ch. piceus is not mentioned in Guilding's essay, and therefore cannot be the type of his genus. We are not concerned with the shadows of species dimly visible upon Guilding's pages, but with the species actually enumerated by him, with name and refer- ence. (2). Franciaia being founded upon the type of Guilding's Acanthopleura, falls as a synonym.
The eyes, in this genus, are generally obliterated by erosion except at the edges of the valves, but they are present in young Individuals, as in Tonicia. They are smaller than in Tonicia, and more numerous. In Mesotomura they are excessively numerous, minute and oval. In Acanthof)leura spiniger they are larger, cir- cular, and scattered around the bases of the tubercles on the lateral areas. In Maugeria granulata they are more numerous and more scattered.
The interior layer of the valves is very solid and dense, as in JSudoxochiton and Tonicia, even the jugal tract inside and the slit- rays lacking punctures. The tegmentum is deeply grooved over the teeth and sutural-plates.
Although but few well- differentiated species of A canthopleura are known, the range of individual and local variation is great, and con- sequently an extensive literature has arisen, and the synonymy of the species is exceptionally involved. It is not improbable that some other valid species exist, but if so, they have not yet been recognizably defined.
The group Lucia Gld. (Lucilina Dall) has been considered a sub- genus of Acanthopleura, but it proves to be a synonym of Tonicia.
The genus Acanthopleura differs from Tonicia mainly in the duller and sculptured valves, having the tegmentum more broadly inflexed over the posterior margins ; in the more numerous, smaller eyes, the fleshy girdle clothed with large or small calcareous spines, etc. It is not especially allied to any other genus, but some species of Liolophura, a genus near Onithochiton, are externally very similar to species of the subgenus M<intjc,-i<i. They may be distinguished at once by the smooth toothless ridge in place of the insertion-plate in the tail valve.
All of the species can be readily identified by the following key, whether the girdle-covering be preserved or not. It is necessary to remove the posterior valve of a specimen, which may be done by soakin- it fur .some hours in warm water. The arrangement here given is believed to be perfectly natural.
ACANTHOPLEURA. -' 1 i
n</ '• nitlm),!, urn.
A. tnMrtion-plate of tail-valve long, civiinlatrd niit.-id«!, and with a niiMliaii slit In-hind, other slits suhobsolete or wanting ; girdle beset with spike-like spines; sinus denticulate ; inte- rior purple-brown in the cavity and transversely engraved ; the sutural-plates white, (Mesotomnra), A. echinatwn.
AA. Insertion-plate of tail-valve long, crenulated outside, and cut by numerous slits; median valves much wider across the sutural-plates than across the tegmentum or outer coat of the valve ; interior not engraved (Acanthopleura s. s.}
a. Interior purple in the cavity, sutural-plates white ; median valves occasionally Radsioid ; sinus of second valve feebly denticulate ; girdle broad, with long black spines; exterior black, A. spinosa.
aa. Interior livid-flesh or livid purple-colored ; median valves 1-slit ; sinus smooth ; girdle wide, with numer- ous spinules; exterior dull, generally eroded,
A. spinigera.
AAA. Insertion-plate of tail-valve short, blunt; median valves as wide or wider measured across the tegmentum than across the sutural-plates ; sinus smooth.
a. Insertion-plate of tail-valve cut into teeth by 7-11 well- developed, subequal slits (Maugeria.)
b. Interior sea-green (intense or faded), with a black tract behind the sinus ; spines of girdle very small, valves generally eroded,
A. granulata.
aa. Insertion-plate of tail valve crenulated, having an oblique slit on each side, the ridge between them either continuous or unevenly serrated (AmphitowivraJ
b. Median portion of tail insertion-plate irregularly serrated, but without true slits like the lateral tail slits; cavity of valves purple-black, sutural- plates white ; valves usually not eroded outside, uniform black, granulated at the sides ; girdle- spines rigid, black, tipped with butK
A. brevitpinotci.
218 ACANTHOPLEURA.
H>. Interior of valves blue-white, with a black tract behind the white-edged sinus; exterior black with a light stripe on each side of the dorsum, sides granulated ; girdle black, A. borb»
Subgeuus MESOTOMURA Pilsbry, 1893.
Me*otomura PILS., in the Nautilus vi, p. 105 (Jan., 1893). — Core- ]>hinm GRAY, P. Z. S. 1847, p. 65, 68.— Not Corephium BROWN, 111. Conch. G. B. edit. I, 1827.
Acanthopleura : Valves transversely engraved inside, and having the sinus denticulate ; tail valve having a long, continuous insertion- plate, slit only in the middle. Girdle beset with spike-like spines.
A monotypic subgenus related to typical Acanthopleura. It is remarkable for the stout spines of the girdle, the long, continuous insertion-plate of the tail valve, and the finely engraved interior. In the last character it can only be compared with Enoplochiton /</'/' r, which also resembles the present form in having oval eyes in the shell. In Afesotomura these eyes are excessively numerous, exceeding those of other Acanthoids in number.
A. ECHINATUM Barnes. PI. 47, figs. 6-17.
Shell oval or oblong, solid, rather depressed but carinated on the dorsal ridge, the lateral slopes slightly convex. Dark brown ; where eroded soiled white.
Valves strongly beaked, having a narrow, smooth and elevated dorsal Ixnnl, with a shallow groove on each side of it, the sides of the central areas doxelij and deeply engraved with fine flexuous grooves. Lateral areas but little raised, shining, having several radial ';/' iin.-ifiilin ntnmling upon a smooth ground, which is closely .<tii,ldcd n'lth minute eyes, or the pits left by their destruction. Anterior valve having radiating, spaced rows of pustules; posterior valve having the mucro elevated ami near the posterior margin.
Interior white, unicolored or stained with reddish in the depth of each valve ; under a lens it is seen to be finely, closely engraved with transverse lines and elongated punctures on the forward slope of the central callus, and on the jugular area (fig. 12). Slits in anterior valve ft, central valves 1, posterior valve 1 ; teeth long, strongly pectinated. Sinus finely denticulate in all valv< -.
v< LHTBOPLB1 RA,
(iinllr liroad, llr-hv, l»«>.-t with strong spike-like ipL
Lrill- rxtrml the whole length (.ftlir f'"<>t.
ih mo, luvadth .v> mill.: divergence 1 1.")°-1200. Length 68, i.n-a.lth 40 mill.
J'.ivt.i, /V/-// , Dr. \V. B.Jones); <;<//<//"'.'/<>* (P. Ac. Coll.) : Val- parai.«>, Chili ( Fivmbly.)
Chiton whiiKitu* BARNES, Amer. Journ. Science and Arts, (Silli- many) vii, p. 71, t. "», f. 4«, 4b. (1823).— SOWERBY, Conch, rilu.-tr., f. 47 (young). — GMton tvberculiferui SOWKKKY, ('at. Tankerv., p. 29, no. 688 (1825).— Chiton .</>/'// //r/-//x FREMBLY, Zool. Journ. iii, p. 196, Suppl., pi. 16, f. 1 (1827).— Chiton aculeatu* REEVE, Conch. Icon., t. 9, f. 49. Not C. aculeatn* of DESK, et al., nor of Linn. — Chiton (Corephiwn) spinifents Frembl., STEARNS, Proc. U. S. Nat. Mus. xiv, 1891, p. 334.
This large, spiney species is not likely to be confused with any other, being very distinct in external features as well as in the peculiar insertion-plate of the tail-valve, the engraving of the inte- rior (reminding one of Enoplocliiton niyer and Chiton granosus), and the denticulate sinus. The girdle spines are frequently encrusted with a white calcareous deposit, converting them into globular pellets. The young shell also lacks slits in the posterior insertion- plate (figs. 15-17, x 2) ; and the adults sometimes show an addi- tional shallow notch or two near the median caudal slit.
Subgenus ACANTHOPLEURA, 5. sir.
Acanthopleura GUILDING, I. c. (part), and PILSBRY, The Nauti- lus vi, p. 105, Jan. 2, 1893. — Frantisia CARPENTER in DALL, Proc. U. S. Nat. Mus. 1881, p. 284, 289, 290 (1882.)
Acanthopleura: Tail valve having a long, many-slit insertion- plate, crenulated outside ; median valves much wider across the sutural-plates (or articulamentum) thau across the exposed portion (tegmentum.)
The facts which cause me to consider this the typical group of Acanthopleura have been discussed above. The affinities of the sub- genus are with Mnuyerin and with Mesotomnra. With the latter it agrees in the coarsely spiney girdle, interior coloring, denticulate sinus and long insertion-plates; but it differs from that group in having a many-slit tail-plate, in the frequent (or usual) plurality of side-slits, the nearly smooth exterior, etc. In the form and dentic-
220 ACANTHOPLEURA.
ulation of the valves, and in interior coloring, A. spinosa is very closely allied to A. -•/>/»/;/< r Sowb., from which the occasional radsi- oid slitting, and the feeble denticulation of the sinus in the second valve, separate it specifically. Dr. Carpenter's subgenus Frandsia included A. spinosa only.
A. SPINOSA Bruguiere. PI. 45, figs. 80-87.
Shell oblong, depressed, smoothish and black ; girdle wide, covered with long, brittle black spines.
The valves are smooth except for growth-lines on central areas and some inconspicuous radial wrinkling or obscure granulation on the vt'ry feebly defined, small, lateral areas. End valves somewhat rugose-granose radially, the mucro posterior.
bmdepwrpl+redJnthe middle, white on the sutural-plates and the region of the lateral slit-rays. Sinus of second valve cut into delicate square denticles by short linear slits, but in the other valves the denticulation is obsolete. Slits in anterior valve 15, central valves 1 or 2, posterior valve 10 ; teeth of end-valves long, grooved outside and crenulated at the edges, the posterior teeth vertical ; teeth of intermediate valves triangular, the posterior tooth, when present, very small. Sutural plates long, separated by a deep sinus broader than the plates.
Girdle wide, rusty, beset with long brittle black spines (fig. 86.)
Length 50, breadth 28 mill.
Albany Island, £ape York, North Australia (Challenger.)
Chiton *pinn*u8 BRUGUIERE, Journal d'Histoire Naturelle, i, p. 25, t. 2, f. 1, 2 (1792).— LAMARCK, An. s. Vert, vi, p. 321 (1819). — SOWI-:I:I;Y. < ieuera of Shells, Cephala, Chiton, f. 1 ; and Conch. Illustr. p. 1, f. 151.— REEVE, Conch. Syst. ii, p. 12, t. 134, f. 151 ; and Conch. Icon., t. 9, f. 51. — Framisia spinosa CARPENTER MS. — Mn <«j<rin .<pino*u* GRAY, Guide Moll, B. M., p. 184. — /'/•<// spino*a HADDON, Challenger Rep., p. 30.
The radsioid slitting of some of the valves and the lack of distinct areas and valve sculpture, well distinguish this species. The >lits are really very short, but are continued on the outside as grooves, up to the eaves. The eyes appear as minute amber colored heads, sparsely scattered down the forward half of the lateral areas, but scarce ly arranged in rows. Poorly preserved or very old specimens show their pits only.
\< \M n»ri.i.ri: \. •_>•_' 1
Nutta/linn .<C'ibr<i live. l»rar> ;i -li-lit resemblance to thin species, but it is diMeivnt.ly sculptured, has smooth teetli and los -piny girdle. The tail plate of A. spinosa is like that of Kntli'ii-um /»,//- icata, on account of the long, vertical teeth.
A. SPINIGER Sowerby. PL 48.
Shell oblong-oval, moderately elevated or depressed, lusterless, microscopically granulated an<l having a more or less developed sculpture of granules which either* stand distinct or coalesce to form concentric wrinkles. Color dead-leaf brown or soiled whitish where eroded; generally black at dorsal ridge and sides of each valve or some of the valves ; on each side of the black dorsal stripe there is generally a streak of green. Girdle broad, black or alternated with whitish. The valves are rounded at the ends, somewhat beaked ; lateral areas but little raised, granulated or wrinkled, the forward part crowded with microscopic bead-like amber eyes. Central areas having wrinkles of growth and sometimes low, scattered granules, more numerous and stronger at the sides. Posterior valve having the mucro somewhat behind the center.
Interior of a purple-brown color, darker in front of the callus of the valve and on the sutural plates, lighter behind the callus of the valve. Sutural-plates broad, extending laterally much beyond the rounded ends of the tegmentum. Sinus rounded, sometimes black- edged. Anterior valve having 9-11, central valves 1, posterior valve about 7 (6-10) slits ; teeth pectinated, those of the tail-valve much longer than the eaves.
Girdle broad, closely covered with calcareous black or buff spines
Length 70, breadth 43 mill.
Fiji Is. ; Viti Is.; New Caledonia (A. Garrett in Phil. Acad. Coll.) ; Cagayait, Isl. of Mindanao, and Siquijor, Philippine Is. (Coming) ; New Guinea, New Ireland, and Tonga-Tabu, (Quoy and Gaimard) ; Port Essington (Jukes) ; Port Molle and Clairmont and Bird Island (Coppinger); Lat. 10° 36' S., Long. 141°, 55' K, Albany Island, Cape York, North Australia, in 6 fms. (Challenger.)
? Chiton aculeatus LINNE, Syst, Nat. x, p. 667 (founded upon Rumphius Amboinische Rariteitkamer, pi. 10, fig. 4.)
Chiton nicobaricus aculeatu*, CHKMN. Conch. Cab. x, p. .">7">, f. 1692. — Chiton aculeatus SPENGLER, Naturhist. Selskabet, iv, p. 78. — Chiton aculeatus QUOY & GAIMARD, Voy. de 1' Astrolabe, Zool. iii, p. 373 ; atlas, t. 74, f. 1-5 (1834).
v PHOPLEURA,
3OWB., M n. Hist. 1*40, p. 287, Suppl. ])1. xvi,
f. 2; I'. /.'>. 1841, p. 61; Conch. Illustr., f. 68.— REEVE, Condi.
.1. 14, 1'. 7-"). — Mnii^f'-ri'i ,*j,ini'j'ra GRAY, Guide Moll. B. M., ]). 184 (1857). — Ac.itnthojJi ">-<i .*/f!it!<i'-rii Cri:., MS. and DAI.L, ! U. S. Nat. Mns. 1*S2, ]>. 80. — Chiton (Acanthopleura) spiniger SMITH, Zool. Coll. H. M. S. ' Alert/ p. 81 (1884) ; P. Z. S. 189J , p.
-Awmthtif,/, urn *i>ini<j<-r HADDON, Challenger Polyplac., p. I':). — Ac'tnfh'ijil''iira balnnsce ROCHEBR. Bull. Soc. Philomath. Paris, 1881-2, p. 1!»7.
oil-nil! ( JIIAY, Guide Moll. B. M., p. 184 (no descrip- tion or figure). — ?? Chiton gemmatus BLAINV., Diet. Sc. Xat. xxxvi, p. :.44.
It is now impossible to prove that this is, or is not, the
>/">• of Lin IK' ; but any one who will consult the original
description, " C. testa octovalvi striata, corjtore su bactdeato" then turn
to Riimphius' figure cited as an illustration, will be prepared to
acquiesce in Hanley's suggestion (Ipsa Linn. Conch.) that the
'•s be dropped us unidentifiable. Gmelin had no better informa-
tion upon this species than we; and therefore his additional citations
jures are valueless. The mere fact that the figure cited by
Limn' represents an oriental species is offset by the absolute impos-
sibility of knowing that it was an Acanthoineura.
Besides the localities given above, this species has been reported from Sue/, by Is>el (Mai. Mar Rosso p. 235, and see also Cooke, Ann. Ma-. N. II. 1885, p. 276), from Aden by Haddon (Challenger Polyplar., j>. 24). It has been figured from the Red Sea by Savigny (see pi. •">, ii.ur>. 4, 1-2 of his folio). Probably Savii_rny's \\^. 7, 1-3 of the same plate represent a young shell of the same, although I havr sri-n none closely corresponding in sculpture. The eyc> arc distinctly drawn by the artist, a rather remarkable circumstance when we remember that no subsequent illustrations of Chitons show them ! Additional localities are Si n- /r«I<ni<l reported by (£. A < \. and Jfnl.-mlii'li, .Juj,,ni by Sclnvnck (Amurl. Moll. p. 27.")': but two localities must lie regarded as doubtful until confirmed by i fri'-h specimen.- or a critical re-examination of the specimens and data in each <
The study of the Indo-Paeitic Acanthopleiiras may be somewhat >implilicd l»y the elimination of i'l) A. f>or/>o, ,!,;/, characteri/ed by a •ail-valv- and (2; the " Aninth-
ACAM HMI-I.I i i:\. ; Au-tralia and the so-called Acant lioplmras of .Japan,
which arc characterized i>y a flat ere-centie callu- in pla<-»- of the
teeth in ilic tail-valve (pi. .~>3, fiir. -V
Tin; variation ot'thi- Speciei is irr«-at, and a number of Hiibspeeilie or varietal forms will probably be distinguished eventually. My material is not extensive enough to permit me to diagnose these, or to indicate their areas of distribution ; and I therefore offer below the original descriptions of the several described forms.
Typical >IMM»;I:I: is characterized by the possession of longer spines than any of the other forms. It is thus described by Sower by :
C. spiniger Sowb. (pi. 48, fig. 22). Shell depressed, ovate-elong- ated, all over granulated ; valves reclining, ends rounded ; girdle wide, furnished with numerous subarcuate spines. .Length 2'1,
width 1'5 inch. Habitat ? Mus. Stainforth. Another spini-
ferous species, rather narrow in proportion to its length ; depressed and finely granulated ; the valves are rounded at the lateral extrem- ities, with their apices leaning backward, and their lateral areas scarcely distinguished ; numerous slightly curved spines, nearly one- half an inch long, cover the margin ; general color like a faded leaf, with dark patches of reddish-brown covering the lateral and part of the central areas of some of the valves, and a dark dorsal band bordered by bright green and white (Sowb. in Mag. Nat. Hist.)
The fig. 22 is a copy of the original one published in Mag. Nat. Hist., and fig. 23 of that in the Conchological Illustrations, which probably represents the same specimen. Note the length of the girdle-spines.
Reeve's figure (pi. 48, fig. 27) represents a larger specimen, collected by Cuming in the Philippines. In this the spines are much shorter. Figs. 24-26, pi. 48, represent valves from a specimen very similar in all respects to Reeve's figure (see pi. 48, fig. 27). The granulation is rather obscure, or transformed into low wrinkles. The spines on the very wide girdle are both long and short (1-1 \ mill.)
Figs. 31, 32, pi. 48, are drawn from a specimen from the Viti I>. collected by Andrew Garrett. In this specimen the dorsal ridge has a blackish-green band with a wider fleshy-white triangle on each side of it, and a streak of green, the rest of the surface of the valves being black except the large ashy-eroded patch on each side of the black (eroded) beaks. The central areas have some scattered gran-
224 ACANTHOPLEURA.
ules on the light bands, and toward the diagonal lines ; the lateral areas have rather coarse, irregular granules. The girdle is covered with alternate black and whitish patches of spines, theee being all curved like a Dentalium, rather blunt, the longer of them measuring about 2i mill, in length.
Another specimen, from New Caledonia, is similar, but has no white patches on the girdle, the spines being 3-3£ mill, long, and black, often tipped with light color.
The C. macgillivrayi Ad. (P. Z. S. 1855, p. 120) seems to be very similar, to this variety, if not identical ; the original description follows :
C. macgillivrayi A. Ad. Shell oblong-oval, a little elevated ; black, the central areas painted with two pale longitudinal stripes; valves obtuse, under a lens seen to be most minutely granulated, ornamented with concentric undulating rugose-grained line ; ter- minal valve umbonated in front, umbo rather smooth, slightly pro- duced; girdle set with black, curved, slightly obtuse calcareous spines. Feejee Islands, on the reefs ( J. Macgillivray). This is a well-marked and handsome species, rather more than two inches in length ; the surface of the valves is finely granulated and orna- mented besides with subgranulated, wavy, concentric elevated lines ; the central areas have a pale greenish band on each side of the umbo. (Ad.)
Carpenter gives the following notes upon the types : Four spec- imens, with A. Adams' autograph label. Bristles rather long for the group, crowded and curved, black, but often tipped with light as in brevispinosa. Sculpture with granules like borbonica in the young, but soon changing to concentric wrinkles. Mucro prominent, somewhat antemedian, the posterior slope convex. Jugal area granose ; in one specimen only are there white streaks making V's on the valves. Sculpture of central areas gradually changing from grains into wrinkles toward the diagonals. Lateral areas scarcely distinguished ; concentric wrinkles predominating. On the terminal valves the sculpture is much finer, the rugulte breaking up into grains. Inside color dark. The divergence is very variable, one specimen being quite elevated, the others flatter; measuring 103°, 126°, 114°, 129°.
The >ir<i/t<itns of Reeve seems to be an unusually granose example of spiniger, such as that figured on pi. 48, fig. 28. The description here follows:
ACANTIIMI-I.I DBA,
C. grnnatn* Kecve (pi. 4<H, figs. 29, 30). Shell ohlc.n. valves strongly, roughly Drained, especially at. the sid«-s ; umbos smooth ; dirty ash or stone color, grains blackish, nmbonal eminence blotched with black; ligament horny, jet black. Habitat -- ? (Re<
The figured type, according to Carpenter, has lost its anterior valve and girdle spines. The tail-valve should be examined in order to tell whether it is a specimen of spiniger or of borbonica, but I am disposed to believe it the former.
Fig. 28, of pi. 48 is drawn from a large specimen belonging prob- ably to the fjrdnatus form. The dorsum has a green band flanked by creamy-flesh colored wider bands, more or less suffused with green. The surface is very strongly granulated.
Reeve's C. CUNNINGHAMI, to which piceus Rv. non Gmel. and obesm Shutthv. may be added, probably represents a variety char- acterized by the large size, fine girdle-spines, etc.
(7. ciuminghami Reeve (pi. 49, figs. 33, 34). Shell oblong-ovate, valves rather thick, concentrically ridged throughout, radiated from the umbones with raised striae ; posterior terminal valve retusely umbonated ; lateral areas scarcely distinguished ; greenish-black, valves longitudinally painted in the middle with a brown band ; ligament horny. (Reeved)
Australia.
., Conch. Icon., t. 27, f.181, Oct. 1847.— " C. magnificus Gray?" SOWB. Conch. Illustr., p. 2, fig. 52 (not described.)
The identity of the undescribed C. magnificus (Gray) Sowb. non Desh., with Reeve's C. cunninghami, is evident, the figures being extremely similar.
Carpenter gives the following notes on the type : " One specimen, marked by Baird (and rightly, I think) to be the same as piceus Rve. The valves are remarkably well grown, in quiet waters, and the sculpture is rather differently developed in consequence. The girdle has dried in around the valves, and the hairs are worn off except in the sutures, where they are short, crowded and black. Reeve's figure is very good except that the jugular parts appear too decided; they are simply worn smooth. The mucro is elevated, central, posterior slope convex; jugular area eroded ; central areas wrinkle-granose, rugulre radiating forward, more or less inter- 15
ACAXTHOPLEURA.
rupted into (rrainile? by wrinkles of increment ; lateral areas scarcely defined. Divergence 127°.
The following is believed to be practically identical :
C. ptceus Reeve. (PI. 49, figs. 38, 39). Shell ovate, rather thick, valves concentrically flatly ridged, interstices between the ridges elevately striated and sometimes grained, umbos a little beaked ; pitch-black, greenish on each side the umbonal summit ; ligament horny, profusely beset with whitish short calcareous bristle-like pro- cesses. New Holland, on the rocks (Cunningham). This I believe to be the true C. piceus ; it is a thick ponderous shell, of which the ligament, when in a good state of preservation, is covered with calcareous bristle-like processes, as in C. spiniger but much finer. (Reeve.}
Chiton i>it-eas REEVE, Conch. Icon., t. 13, f. 70, March, 1847. — \8, P. Z. S. 1867, p. 223.— TAPPARONE-CANEFRI, Zool. Viag. Magenta, Malacologia, p. 77 (1874). — C. obesus SHUTT., Bern. Mittheil. 1853, pp. 67," 79.
Angas says that this species is freely distributed on most parts of the coast of New South Wales. The specimen commented upon by Canefri was collected at Sydney ; but both may be founded upon wrong identifications. Carpenter writes of the types as follows: "Four specimens from Australia. The figure of Reeve is much larger than the type, and would stand well for a perfect The largest shell measures: length 77 J, breadth 49 mill., divergence 108°. This is a more raised shell than cuttning- hniiii, probably from its having grown in rougher water. Spines very short, black, sometimes white. Sculpture almost entirely worn away in all the specimens ; when seen it consists chiefly of concentric wrinkle.-: more or less broken into granules. The lateral areas are scarcely distinguishable; mucro very perfect, post-median like 'inyhumi, but rather more elevated, as is the rest of the shell."
Subgenus MAUGERIA Gray, 1857.
.!/'/<"/' rm (i KAY, < iuide Syst. Dist. Moll. IJrit. Mas., p. 183 (in part). — Ac'iHthojileiira CAKTI \ri.i:, Table Reg. Chit. 1873, and Dal I. 8, Nat. Miis. 1881, p. 284, 289, 290 (in part); Not
/ Guilding, q. v.
Exterior lusterless; tail valve having numerous (7-12) slit- in the short crenulated insi-rtiun-plate, median valves 1-slit, the exposed coating or tegnientum widrr than the articulanu-ntuni or inner layer;
227
sinus not toothed, the sntural plates connected across it; thick, densely beset witli calcareous spinelets. Type < '/t. 'jranulatus (Jinel.
ThU •ubgenua or section differs from Ac<inthnj>l>,i,-<i and Mcsoto- mnra in the shorter, blunt tail insertion-plate, and the proportionate breadth of the outer and inner layers of the median valves. It differs from Amph Honiara in having numerous equally developed slits in the insertion-plate of the tail valve.
VMTLATA Gmel. PL 50.
Shell oblong, moderately elevated or roundly arched. Surface almost always eroded, dull, ashy or cinereous, generally with a patch of dead-leaf brown on the ridge of each valve ; when not eroded, it is tawny-brown or black-brown, with a pair of diverging whitish, buff or pinkish stripes.
The valves are beaked, solid and thick, with somewhat raised but ill-defined lateral areas. When not eroded, the lateral areas and pleura are closely granulated all over, and the end valves likewise; but this sculpture is generally preserved only at the lateral extrem- ities and the protected anterior margin of each valve. The mucro is swollen and posterior.
Interior sea-green, often varying toward lead-blue, or on the sutural-plates fading to nearly white ; each median valve having a black or purple- black tract between the sinus and the summit of the callus, this tract being square or 2-branched at the ends. Anterior valve having normally 8-10, central 1 (rarely 2), posterior valve 9, (occasionally 7-14) slits; teeth long and very deeply pectinated outside ; teeth of tail-valve short and obtuse, directed forward, very deejily pectinated outside and on the edge. Sinus slightly concave, or convex and notched at the sides, not denticulate.
Girdle thick and fleshy, densely covered with short, unequal spine- lets (pi. 50, figs. 40, 41, x 13) which are short, calcareous, and either black or white ; the black spines (fig. 41) being frequently longer than the white, and straight or nearly so; the white spines (fig. 40) are short, very unequal and shaped like the shell of Oididus.
Bermuda; Bahamas; Ch<irl»tt> Jlnrbor, Vaccas Key, etc., Flnriil'i : <////'/v I !''.>•/ Indie^ southward to Trinidad and the Spanith M<i in.
Chi f on in<i</ell(t.r,iciis GMKLIX, Syst. Nat. xiii, no. 12, p. 3204. (— Chemn. viii, p. 279, pi. 95, f. 797, 798, Chit»n mittj'-/laniciis).-~
228 ACANl IlnPI.KURA.
WOOD, General Conchol., p. 18, t. 3, f. 6 (1815).— Chiton granulatu* GMEL., /. c. no. 16, p. 3205 (=Die j»«-h.-«-/<ir<irze granulirte Chiton CHEMNITZ, Conchyl. Cab. viii, p. 284, t. 96, f. 806).— WOOD, Gen. Conch., p. 9. — d'ORB., Moll. Cuba (Ramon de la Sagra, Hist), ii, p. 200 (1853). — Chiton i>iceus GMEL., I c. no. 17, p. 3205 (Chemn. viii, p. 285, t. 96, f. 807-810).— WOOD, Gen. Conch., p. 8, t. 1, f. 3.— SOWERBY, Conch. Illustr. f. 147.— SHUTTLW., Bern. Mittheil. 1853, p. 78, and of most later writers on the Antillean fauna. — Chiton occidental™ REEVE, Conch. Icon., t. 14, f. 77a. (1847). — Chiton sala- '!rr SPENGLER, Skrivter af Naturhist. Selskabet, iv, p. 80 (= Chemn. viii, f. 806. — Chiton tuberculatus L., SCHROETER, Einleit. iii, p. 494, t. 9, f. 19 ("Der cylindrische Chiton ") ; not C.tubwula- t\i8 Linne. — Chiton nnguiculatus BLAINVILLE, Diet. Sc. Nat. xxxvi, p. 544. — (7. conrexus BLAINV. /. c. — Chiton (Acanthopleurd) blaum-ri SHUTTL. Journ. de Conchyl. 1856, p. 170. — ? C. (A.~) mucronulatus SHUTTL., Bern. Mittheil. 1853, p. 79.
This species is the common Chiton of the West Indies, being abundantly distributed throughout the group, the specimens before me being from the following localities : Bermuda (Heilprin) ; Key Vaccas, Florida (Calkins, Hemphill) ; Bahamas (H. C. Chapman, J. J. Brown, F. Stearns) ; Jamaica (Johnson and Fox) ; San Dom- ingo (Gabb); St. Thomas (Swift); Dominica (Sharp) Monos, (Sharp) ; Atlantic coast of Costa Rica (Gabb). The specimens are almost always eroded, the original color and sculpture being quite lost. Although the species is very variable, no local forms deserving varietal rank are known to me.
Figures 39-41 represent a St. Thomas specimen, eroded in the usual manner. Fig. 48 is also drawn from a St. Thomas specimen in which the sculpture is perfectly preserved, and the color uncom- monly dark.
Figures 44-47 represent valves of examples from St. Domingo. The non-eroded forward part shows a central brown band, with a flesh-colored band on each side of it. This coloring is also found in most specimens from Florida Keys (fig. 43), Jamaica, St. Thomas. Specimens from the Bahamas have the two light stripes blue-white, and are strongly corrugated.
Tho tail-valve varies greatly in respect to the prominence of the mucro. In some specimens (fig. 46) it projects beyond the pos- terior edge of the valve ; in others it hardly attains the edge; but these variations do not seem to be correllated with other characters.
Li \M -IIMI-I i ri:\. 229
The identity of C. ma<j>ll<itii<'ii* ( \ in. and Chcmn. with tlie West Indian species, although extivmelv probable, cannot be regarded as absolutely established. At all events the name is hardly acceptable, for no Antntfio/ilcnm of this type has been collected at or near the Strait of Magellan. Rochebrune's citation (Moll. Cap Horn) is worthless, on account of his ignorance of generic and specific charac- ters in this group, and his false synonymy in the case of this species. Gmelin's C. (jrnnulitns, the next name in order of priority, was founded upon specimens from St. Thomas excellently described and figured by Chemnitz. The identity of the next form described by Gmelin, jritttf*, is also moderately sure. Reeve's C. occidentalis {see pi. 50, fig. 42) is an ordinary form of granulatus.
Shuttleworth has described two West Indian Acanthopleuras of which I have not seen authentic examples. His descriptions here follow :
C. (Acantfiopleura) inner oiwlatus. Shell oblong-ovate, elevated, narrowed in front, black-brown, unicolored ; valves all over very minutely concentrically punctate-striate, carinated dorsally, pro- duced backward in a short apex ; lateral areas slightly elevated. Girdle spotted with white, having scattered very minute, sand-like grains. Length 9, breadth 6 mill. Porto Rico, Blauner ! Described from a single specimen ; distinguished from the young of granulata by the form and especially the very minutely sanded girdle. Shell inside dull whitish, slightly greenish.
This may prove to belong to some other group. C. (Acantho- pleura) blauneri Shuttl. was founded on a single black-brown spec- imen from Porto Rico, having unicolored black girdle densely -clothed with very minute spines, more minute than in piceus, from which blauneri also differs in being more depressed and more minutely sculptured. Length 52, breadth 32 mill. I do not see that this falls outside of the well understood range of variation of A. granulata.
The following unfigured form may prove to be a distinct species if the locality be confirmed.
Chiton (Acanthopleura) piceolus Shuttl. Shell ovate, wider behind ; obscure olivaceous, maculated with black at the middle of the back and at the sides; valves all densely and minutely pus- tulose-granulate ; areas entirely obsolete. Girdle minutely and very densely sandy-spinulose, alternately maculeated brown and white. Length 10, breadth 6 mill. (Shuttl. Bern. Mittheil. 1853, p. 82.)
Tenerife, Canaries, (Blauner) ; rather common.
230 ACANTHOPLEURA.
Intense black-green inside. Color, pattern and sculpture are as in young C. piceus Gmel., but it differs in the much smaller, more delicate girdle spicules. (Shuttl.)
Subgenus AMPHITOMURA Pilsbry, 1893.
Amphitomura PILS., The Nautilus, Jan., 1893, p. 105. Type Ch. borbonicu* Dh.
Girdle and all valves but the eighth formed as in Maugeria. Tail valve having the insertion-plate very short, with blunt, crenulated edge, and a single shallow oblique slit on each side, and sometimes some uneven serrations in the middle.
The Mopaloid slits of the tail-valve are very peculiar, but the structure is fore-shadowed in some forms of Maugeria.
A. BORBONICA Deshayes. PI. 45, figs. 76, 77, 78, 79.
Shell oblong, rather elevated, solid, roundly arched, dull bln-k with a white stripe on each side of the median black band; rusty blackish and gray when eroded ; girdle black.
The lateral areas are but slightly raised, and are densely, fitn-ly hired with close radiating rows of granules; the sides of the central areas are also granulated adjacent to the lateral areas, but toward the middle this sculpture disappears, leaving only a faint microscopic granulation. End valves radially, densely, granulated, the mucro posterior, rather elevated.
Interior blue-white, each median valve having a broad black square- ended crescent in front of the callus, the inflexed posterior margin ashy-olive, lateral triangles lead-white. Sinus deep, rounded. Anterior valve having 10, central valves 1, posterior valve 2 slits (figs. 76, 77) ; teeth pectinated, those in the front of the head-valve short. Eaves wide, black, channelled along the teeth. Muscle impressions on sutural plates and end valves deep.
Girdle fleshy, black, covered with black spinules about li millim. long.
Length 50, breadth 30 mill. ; divergence about 125°.
Mauritius ; Reim Mm.
Chiton borbonicus DH., Moll. Reunion, p. 37, t. v, f. 12, 13.— C. (Acanthojilfnra) horbonicus Dh., MARTENS in Mobius' Reise nacli Mauritius, p. 300. — ? ? ('hit.,,, ntbvbmu WOOD, Index Test. Suppl., t. 1, f. 4.
ACANTiii >ri I ri: \
Keadilv rec.. Lrni/ed l>y the Mack, irranulated ridtt, an. I HBOOthet
;riped rid.ire, in connection with the peculiar insertion-plate of
tin- tail valves. Smith has placed the species with douht in the
synonymy of A» »i»iiii[icr, where it certainly does not belong ; and
Martens, also erroneously, suggests its identity with ('It. i>ctli<>l<itn.<
Sow.
The insertion-plate of the tail-valve, while in some specimens somewhat uneven, is not often so serrated as in A. br'-rinftinosa. It further differs from that species in the striped back and the interior coloration. The crescent-shaped black patch behind the sinus inside is square or forked at the ends, as in A. granulata, and the edge of the sinus is white.
A. BRI:\ isriNosA Sowerby. PI. 47, figs. 18, 19, 20, 21.
Shell oblong oval, depressed, each valve beaked and concentrically rugose-granuliited. Color black, the girdle narrow, clothed with
The valves concentrically wrinkle-grained at the sides of the central areas, and the ill-defined lateral areas are cut into granules by concentric and radiating grooves. End valves finely grooved radi- ally t finely wrinkled concentrically ; mucro posterior, prominent and rather acute.
Interior blackish-brown or /nirple-browti except the sutural- and insertion-plates which are white. Sinus broad, deep, rounded. Anterior valve having 7-8, central 1, posterior 2 slits and a number of irregular serrations ; anterior teeth moderately long, finely pect- inated outside ; posterior teeth very short, blunt, obsoletely pectinated.
Girdle rather narrow, clothed with rigid black spinelets tipped with buff.
Length 42, breadth 26 mill. ; divergence about 130°.
Johanna, Comoro Is. (Cuming, Cpr.) ; Zanzibar (Cpr.) ; Cape of Good Hope <m<! Mnd<tga*cnr (Paris Mus.) ; Strait ufSnint Vincent, Cape Verde I*. (Cessac.)
Chitnn I,,-, -i-i-tplnoxua SOWB., Mag. of Nat. Hist. 1840, p. 287. t. xvi, f. 1; Conchol. Illustr., f. 136. — KI:I:\I:, Conch. Icon., f. 52. — Acniitln>pl'-imi brcvi-xpinoaa ROCHEBR., Nouv. Arch, du Mus. J881, p. 240.
Part of the localities given above are probably incorrect, A good many shells procured at " Cape of Good Hope" and "Zanzibar"
232
never grew at those places. The evidence in favor of the Comoro Is. is more satisfactory.
This species is closely allied to A. borbonica in sculpture, but it differs in having flatter, thinner valves, longer, white-tipped spines, in lacking the white dorsal stripes as well as in the color of the inte- rior. Finally, the characters of the tail insertion plate differ.
Subfamily LIOLOPHURIN^E.
Median and anterior valves provided with eyes, and having well- developed insertion-plates with slits, the teeth pectinated outside, not thickened at the edges of the slits. Posterior valve with the mucro posterior and terminal ; its insertion-plate obsolete, reduced to a low ridge or flat ledge of callus, which is unslit (except in Schizochiion ) and continuous posteriorly or interrupted in the middle by a caudal sinus. Gills as long as the foot.
This group is closely allied to Chitonidce and has doubtless been derived from the Tonicioid branch of that stock. It is separated from them on account of the degeneration of the posterior valve and esj>ecially its insertion-plate, — a character of vastly less importance than Carpenter supposed. The median notching of the tail valve behind is also extremely variable, as is exemplified by such closely allied forms as Lorica volvox and L. angasi. All of the genera of >nidcet Chiton, Eudoxochiton, Tonicia and Acanthopleitra, show species in which the tail valve has an incipient caudal sinus, or in which the insertion-plate is becoming obsolete, or both conditions. It is only necessary to mention Chiton jugosus (p. 178), Eudoxochiton (pp. 193, 194), Tonicia confossa (p. 210); Acanthopleura sjrinigera, all showing more or less posterior emargination ; Acanthopleura grnnii/nfu and the section Amphitomura have the posterior insertion- plate very short, some forms of the latter having it nearly deprived of slits. Compare with these Schizochitou and Lorica, the latter having the insertion-plate short but distinctly creuulated. It is probable that deposits not older than Miocene will furnish the generic links now missing between the series of forms here included tnd those grouped in L i»lo/> h ///•///</.
It is a notable fa<-t that the generic groups of Toniriitur and
' MMMII to mutually correspond to one another, as though the several generic stocks of the former subfamily had been simul- taneously modified in the same manner, thus:
IJolophnrin;.-. H disposed in radiat.ing hands;!
valves polished and bright colored
n ... . ,, > Ontthochiton.
outside, ponvllanous \vitlnn; girdle
[leathery, nude.
f Eyes scattered among the tubercles!
of the surface, which is rough and
Maugtna < . . ' . ' . .. }• Liolophura.
lusterless ; interior dark ; girdle
[clothed with calcareous spines.
(Eyes very minute, oval, scattered;! surface of valves brown and polished I — 7 , . ,. > Enoplochiton. outside when not eroded, peculiarly sculptured inside.
The genera Lorica and Schizochiton have no representatives in the Toniciitice, for while they are closely allied to the latter, they have been differentiated along a line away from that taken by Onitho- chiton and its immediate allies.
Synopsis of Genera.
A. Median valves having eyes developed only on the diagonal ribs. Sinn* notably narrow and small. Insertion-plate of tail valve a low, rounded, rugose ridge more or less notched or waved upward in the middle behind, or sharp, long and pectinated.
B. Eyes large, situated on the diagonal ribs and on the ribs of the head valve, the latter corresponding to slits in the insertion-plate. Girdle having minute calcareous spines.
Genus XVI. SCHIZOCHITON Gray.
Much elongated. Posterior valve having a deep caudal sinus with one or two notches on each side of it in the insertion-plate. Head valve with few (about 6) slits. Girdle sparsely, finely spinulose, slit behind.
BB. Eyes reduced to minute, fuuctionless punctures on the summit of the diagonal ribs, and entirely absent on the head valve, the riblets of the latter not corresponding to internal slits. Qifdfa dfnseli/ s<'ah/.
Genus XVII. LORICA H. & A. Adams.
Oval or ovate, elevated. Posterior valve having a deep caudal sinus or a shallow wave, the insertion-ridge otherwise uninterrupted.
234 SCHI/OCHIToN.
Head valve with numerous (8-10) slits. Girdle den-ely clothed with minute, convex, crowded scales.
Section LORICA s. str. Caudal fissure deep ; sinus v-shaped ; girdle widest at the sides, slit behind. ^
Section LORICELLA Pils. Caudal fissure reduced to a shallow wave; sinus bilobed ; girdle widest in front, not slit behind.
AA. Eyes developed upon the lateral areas. Sinus wide and large, 'ion-plate of the tail valve reduced to a smooth ledge or rid<jey ha ring no posterior sinus or wave.
Genus XVIII. ENOPLOCHITON Gray.
Valves polished or deeply eroded, dark brown outside and within, having excessively minute eyes scattered over lateral areas and head valve (when not eroded) ; interior very densely and minutely and peculiarly grooved and punctured. Girdle fleshy, bearing separated rude scales.
Genus XIX. ONITHOCHITON Gray.
Valves polished, colored outside, porcellanous and smooth within, having the eyes disposed in radial bands on each lateral area and the head valve. Girdle leathery, microscopically velvety.
Genus XX. LIOLOPHURA Pilsbry.
Valves lusterless, granulated, having the minute eyes scattered over the lateral areas, sides of the central areas and head valve. Girdle densely covered with stout calcareous spines.
Genus XVI. SCHIZOCHITON Gray, 1847.
Schizochiton GRAY, P. Z. S. 1847, pp. 65, 68, 169.
Valves exposed, elongated, beaked, bearing a single row of eyes upon each diagonal rib of intermediate valves and each radiating rib of the head valve, the ribs of the latter corresponding in position to slits in the pectinated insertion-plate. Sinus narrow. Posterior valve having a deep posterior fissure, and several slits on each side of it. (Jirdle slit behind, bearing small calcareous spinelets. Type Ch. incitu* Sowb.
This genus might as readily be referred to Ttmiri!/ur as to Liolo- phurince, for the posterior insert ion -plate is well developed. The
» Ill/in III K.N.
posterior sinus, however, is unlike tin- former group, in which the
tail valve approaches the head valve in form ; and tin- arrant ni'-nt of the eyes is (he same as in Lorir.i, vvliidi has a degenerate tail in<ertion-plate. At the same time, it must be granted tli at tin- differ- ences between Si'hi:in'hif»n and Lnrim a re greater than between most genera of the same family; for in Schizochiton the slits of the head- valve are inimerieall y related to the external ribs; the latter bear and the tail valve has a well developed slit and pectinated insertion-plate.
S. iNviM's Sowerby. PL 51, figs. 1-8.
Shell much elongated, narrow, the valves elevated, somewhat car- inated ; surface lusterless, grayish, obscurely mottled with olive and purplish.
Median valves elongated, beaked, the lateral areas small, slightly raised. Entire surface sculptured with flattened longitudinal ribletsr as wide as their interstices, converging toward the dorsal ridge and somen'hat irregular or wavy on the lateral areas; each riblet where it passes over the diagonal, enlarged for the insertion of an eye. Ante- rior valve (figs. 2, 4) having 6 (sometimes 7 or 8) radiating curved ribs, each bearing a series of eyes, the intervals sculptured with close v-shaped riblets. Posterior valve (figs. 6, 7, 8) having the mucro posterior, the latero-posterior areas tricostate, otherwise sculptured like 'the median valves ; posteriorly it has a wide, deep fissure, extend- ing up to the mucro (fig. 8.)
Interior whitish, stained with purple-brown in the middle of each valve. Sutural plates well developed. Sinus V-shaped. Anterior valve having 6, central valves 1 or 2 slits; posterior valve, on each side of the posterior fissure, 3 slits ; teeth thin, distinctly creii- ulated outside.
Girdle broad, alternately buff and dark colored, the light stripes wider, and as usual, sutural ; rather thinly but in places densely clothed with minute, cylindrical, shelly spinules, part brown, part white. Length 50, breadth 18 mill.
Zebu, (Cuming), and Samboangan, (Challenger), Philip/tines; Raines Island, Torres Straits (Ince) ; Clairmout <IH<! Bird Is., N. E. Australia (Coppinger) ; Sulu Sea (Capt. Chimmo.)
Chiton incisus SOWB., P. Z. S. 1841, p. 61. — REEVE, Conch. Icon, f. 43.—Sehizochiton liu-i^u* GKAY, P. Z. S. 1847, p. 169.— SHUTTL., Bern. Mittheil. 1853, p. 68.— H. & A. AD., Gen. Rec. Moll, i, p. 477,
236 LORICA.
t 54, f. 6, 6a.— SMITH, Zool. Coll. H. M. S. ' Alert ' p. 82.— HADDON, Challenger Polyplac. p. 31. — MOSELEY, Journ. Roy. Microscop. Soc. x x v, p. 37, pi. iv, figs. 1-5 ; vi, f. 5 (eyes). — Chiton elongatus REEVE, Conch. Icon., f. 40. — Schizoch-Uonpolyophtalmus ROCHEBRUNE, Bull. Soc. Philomath, de Paris, 1881-'82, p. 191.
This species is so unlike other forms that comparisons are unnecessary. The eyes are larger than in any other form known to me. A single eye is shown in fig. 3, magnified 200 diameters.
The girdle is not well shown in fig. 1, the spines being too evenly distributed over it. They are always closer at the sutures.
Genus XVII. LORICA H. & A. Adams, 1852.
Lorica H. & A. Ad., Annals and Magazine of Natural History, (2) ix, p. 355 (April, 1852). Only species L. cimolia, Chiton cimo- lius RVE. — Aulacochiton SHUTTL., Bern. Mittheil. p. 68 (June, 1853), type Chiton volvox REEVE.
Valves exposed, not beaked, the lateral areas and end valves with many fine riblets or pustules. Eyes confined to B single series along the summit of each diagonal rib. Insertion-plates blunt, obsoletely pectinated, the slits in head-valve not corresponding to external ribs ; sinus very small. Posterior valve having the mucro posterior and terminal, insertion-plate unslit, obsolete, being reduced to a convex ridge of callus ; posteriorly cleft to the mucro by a deep rounded sinus, or waved. Girdle slit or waved behind, densely scaly.
This is one of the few genera of " irregular " Chitons having a scaly girdle. The eyes seem to be nearly obsolete, and possibly are not functional, although they still are pigmented. In most spec- imens a good hand-lens shows the series of ocular punctures along the diagonal ridge, immediately in front of the anterior row of pustules.
The non-correspondence between slits and external ribs, the scaly girdle, the transverse, unbeaked valves and the toothless posterior insertion-plate, are all characters widely sundering this genus from Schizochiton.
Section Lorica 8. str.
Sinus in tail valve deep; jugal sinus v-shaped; girdle widest at the sides, cleft behind.
LOBIOA.
I. 70LV03 Reeve, IM. 52, figs, 14-21.
Shell oblong, strongly elevated, the dorsal ridge anirular, side- slopes nearly straight. Surface Insterless, finely sculptured, variable in color; sometimes hull' with chestnut streaks and darker angular blotches on the central areas, fewer on the lateral areas ; sometimes the lateral areas are olive-green, the dorsal region light, the sides of the central areas brown or olive. The dorsal ridge is sometimes staim •(! with orange on each valve, and the same color often clouds the sides also.
The median valves are not beaked, even when young, but they are falsely beaked or narrowly projecting at the sinus in front. Lateral areas raised, sculptured with 8-12 low radiating cords bearing rounded pustules, which are more or less entirely lost in adult spec- imens. Central areas sculptured with numerous narrow raised threads parallel to the dorsal ridge, their interstices wider than the threads, and closely latticed across. Anterior valve strongly elevated, curving forward at the summit, the anterior slope being con- cave; sculptured with many radiating riblets which are pustulose when not eroded. Posterior valve small, much depressed, with pos- terior, terminal, elevated mucro ; posterior-lateral margins bounded by an elevated rib ; posterior area extremely small, vertical, perpendicularly ribbed, having a deep rounded excavation behind.
Interior white ; tegmentum reflexed and sculptured along the pos- terior margin of each valve; sutural-plates broad, separated by an extremely small v-shaped sinus in the middle. Anterior valve hav- ing 8, central 1 slit ; slits minute ; teeth short, blunt, finely but obsoletely pectinated outside, and crenulated on the edge. Posterior valve having a low, rounded callus ridge in place of the insertion- plate, its edge unslit, finely and rather obsoletely striated, interrupted by a deep rounded sinus in the middle behind. Eaves narrow, solid.
Girdle wide, bluish with inconspicuous dusky cross bars, slit behind, its surface very densely covered with minute, closely imbricating smooth convex scales (fig. 16.)
Length 70, breadth 38 mill. ; divergence about 90°, the young more depressed.
Port Jackson, Sydney, Watson's Bay and Middb II<irl>or, N. S. Wales; Port Lincoln, S. Australia, under stones at extreme low tide.
238
r/,/Vo/, m/vn.r JiKEvi-:. Conch. Icon., t. 6, f. 31 (Feb., 1847).— /,<>,- it-'t i-ulrn.c (Rve.) IlAnimN, 'Challenger' Polyplac., p. 31. — Chiton cimol!".< Hi: i:\ i :. Conch. Icon., t. 21, f. 141 (May, 1847). — L rhnoli'i \\. & A. AD., Ann. Mag. N. H. (2) ix, p. 355. — ANGAS, P. /. S. 1SG7, p. 224; 1871, p. 97. — Aiilacochiton volvox SIIUTTL., Bern. Mittheil. 1853, p. 68.—? Chiton nulls HUTTON (see below.)
The differences between L. volvox and L. cimolia are easily effaced when a good series is examined. The yoilng show great variation in the pustulation of the lateral areas, the pustules sometimes being scattered, radiating, cords obsolete. The dorsal ridge generally has a central fine carina with a long narrow smooth triangle on each side, but this varies also. The second valve has a rather large median patch of scattered or diverging series of pustules. The color- ing varies a good deal in the series before me.
' I am disposed to consider Hutton's Chiton rudis a synonym of this species, but my opinion is founded upon a study of the original description only, which is as follows :
Chiton rudis Hutton. Oblong; margin with minute scales; valves elevated, flattened on the sides, not keeled ; apex of anterior valve recurved, with its posterior margin slightly convex at the sides and deeply concave in the center ; posterior margins of intermediate valves straight ; posterior valve rather small ; apex posterior, pointed and emarginate. Anterior valve and lateral areas with radiating moniliform ribs ; posterior and median areas widely but rather irreg- ularly, deeply longitudinally furrowed, with narrow ridges between Margin gray, with broad, irregular, reddish-brown transverse patches; valves grayish-brown ; interior grayish-white. Length 1*75, breadth '75 inch. Founded on a specimen in the Colonial Museum, locality not stated. (Hutto.i, in Trans. N. /,- Inst. iv, 1872, p. 179, and Man. N. Z. Moll. 1880, p. 113.)
Section Loricelli Pilsbry.
Sinus in tail valve a mere wave ; jugal sinus lobed ; girdle widest in front, not cleft behind.
L. \\<. AM Adam- and Angas. PI. ~>1, figs. 9-13.
Shell ovate, coarctate and angulate behind, pale brown, variegated with green. Anterior valve concentrically striated and having radiating pustulose ribs ; posterior valve narrow, transversely silicate and densely longitudinally lirate; median valves subcarinated, the
central arras driiM-ly lirat»- and t ran.-vi-r-rl y siilraH-d; tli.- lateral area- elevated, radially lirate, tin- line jmst ulose.
(iirdle moderate, nlivaeemi-, L-sct with minute scales.
Leii-th H>. luva.lth I'll mill. < If. .!</. <t Any.)
Rcij>i<l J»<ii/, \ An.-fi'iilin (Angaa); Camp ('<><-,•, /'„,-/ ./<"•/. vo>,, N. S. I !",//,•.>• llra/ier). In deep water.
Lorica angati II. AD. <fe ANG., I*. 7. S. 1864, p. 193. — ANOAS, 1865, p. is; ; 1S71, p. 97.—Aul«r,,rJn't<,,, angasi CI-K., .)/>.
I have not seen this species, which is here figured for the first time, from drawings made by Emerton for Carpenter, who writes as follows :
" Anterior valve large ; posterior valve small, the mucro terminal, much elevated, prominent ; diagonal ridges elevated ; dorsal ridge acute. Interior : posterior valve a little sinuated behind, the sinus wide; having two callous, subobsolete, slightly roughened ribs in place of the insertion-plates. Anterior valve with 10, central valves 1 slit ; teeth acute, serrated outside and at the edge ; eaves prominent, deeply grooved ; sinus narrow, deep ; the sutural plates separated, but having a lamina between them which is sometimes bilobate or denticulate. Girdle reduced one-half in width behind, and sinuated, very closely beset with solid minute scales, seen under a lens to be obsoletely bilobate.
Length 32£, breadth 22J mill, ; divergence 110°.
" One of Mr. Cuming's specimens is much broader and somewhat tripartite. This species differs from the typical Lorica in the anterior projection of the girdle ; in the minute raised scales, which under the microscope look like grains of wheat set on end ; in the sinus having a separate lamina, somewhat lobed ; in the absence of anterior * false apex ' on the valves ; and finally in the mucro being terminal and but slightly waved, with a correspondingly slight wave in the girdle behind."
The " hairs " shown on the girdle in fig. 9 are foreign to it.
Genus XIX. LIOLOPHURA Pilsbry, 1893.
Liolophura PILS., The Nautilus vi, j>. 105 (January, 1893). — Acanthopleura sp., of authors.
Valves exposed, dull and somewhat roughened, irenerally erodrd outside, with minute eyes irregularly scattered over the lateral i the head-valve and the sides of the central areas. Interior dark
240 LIOLOPHURA.
colored, having anterior and side insertion-plates slit into teeth and sharply pectinated outside ; posterior valve with posterior terminal mucro, lacking the insertion-plate, which is represented by a flat callous ledge. Sinus wide, deep, smooth.
Girdle covered with stout calcareous spines or obtuse club-shaped processes. Type Chiton japonicua Lischke.
The species of this genus have been referred to Acanthopleura, Mmiyrin and Chiton by authors who have mentioned them; but from these groups the characters of the tail-valve at once sunder them. Liolophura resembles Onithochiton and Enoplochiton in hav- ing a callous ridge in place of the posterior insertion-plate, in the pectinated teeth of the other valves, and in the possession of eyes ; but it differs from Onithochiton (a) in the somewhat rawed instead of marginal mucro, (b) in the dullness of the valves externally, (c) in the distribution of the eyes upon the sides of the central areas, whilst in Onithochiton they occupy a band on the forward part of the lateral areas only ; and finally (d) in the covering of the girdle which in Liolophura consists of densely crowded calcareous spines, comparable to the spines of Maugeria. Liolophura differs from Enoplochiton in lacking the interior sculpture and denticulate sinus characteristic of that genus, and in the totally diverse development of the girdle covering.
L. GAIMARDI Blainville. PL 53, figs. 30-35.
Shell oblong, depressed, roundly arched. Surface lusterless, buff- gray, marked at sides and on ridge of valves with black. Girdle tessellated light and dark, having a light bar opposite each suture, or having dark or light larger patches.
The valves are somewhat beaked, but always considerably eroded ; lateral areas but little raised, concentrically wrinkled toward their bases, studded with minute scattered eyes appearing as black dots. Central areas wrinkled by lines of growth and having scattered eyes at the sides. Head valve concentrically wrinkled, studded with eyes. Tail valve small, depressed, similar in contour to the median valves, the mucro being posterior and terminal, but eroded.
Interior dark red-brown, whitish on the edges of the sutural-plates and the valve-callus; posterior internal margin covered by the reflexed blackish-brown tegmentum. Sutnral-plates brownish below with a white outer edge ; seen from above they are whitish shading into reddish-brown toward the median sinus; rounded, broadly separated by a very wide, deep, rounded sinus. Anterior valve hav-
i KM oi'HtjRA. 241
ing 9, central valves 1 slit : the teeth deeply, el.xely pertinatrd out- side. Posterior valve having the eaves projecting beyond the l.road, flat crescent of callus which occupies the place of an insertion-plate.
( Jirdle densely clothed with intermingled minute, larger and large calcareous spines, (fig. 31.)
New tiouth Wales (Wilkes) ; Port Jackson (Blainville, Coppinger and Challenger Kxped. > Australia.
Chiton incanns GOULD, Proc. Bost. Soc. Nat. Hist. 1846, ii, p. 145 ; U. S. Expl. Exped., p. 315, t. 28, f. 432, 432a ; Otia, p. 6.— Maugeria invtnus GLD., Otia, p. 248. — Acanthopleura incana E. A. SMITH, Zool. Coll. H. M. S. ' Alert,' p. 81, 1884.—? Chiton piceu* ANGAS, P. Z. S. 1867, p. 223.—Acanthopleura (/) incana (Old.) HADDON, Challenger Polyplac., p. 25 (in part.) — Chiton gaimardi BLAINV., Diet. Sc. Nat. xxxvi, p. 546, (1825.)
This species may readily be separated from all forms of Acantho- pleura by the peculiar flat callus of the tail valve inside, altogether lacking the pectination and slits which are present in Acanthopleura. It differs also in having eyes scattered over the sides of the lateral areas, and in having some of the girdle-spines striated. It differs from the Japanese species in the differently colored interior and sutural-plates, in the details of girdle-structure, etc.
The spines on the white tracts of the girdle are unicolored whitish ; on the dark tracts they are of a uniform black-brown color. Occa- sional spines are striated like the scales of Ischnochiton.
L. GEORGIANA Quoy and Gaimard. PI. 53, figs. 36-40.
Body oval, thick ; girdle narrow, granulose, whitish with 8 white stripes; valves arcuate, flattened, thickly striated ; brown, black in the middle.
The body is short, oval, much swollen ; girdle very thick, little dilated at the sides, covered with very small rounded tubercles, white with 8 black bands across each side. Foot narrow, yellowish. Branchiae reaching to the buccal fringe, which is large. Valves very wide, covering nearly the whole body, semicircular, but little elevated, narrowed, somewhat heart-shaped, very thick ; having concentric striae, the anterior and lateral most marked; of a deep brown color at the sides, lighter in the middle with a black dorsal line ; fourth and fifth valves equal and wider than the others. Inside the valves are of a violaceous brown ; median valves with an arcuate thickening. The sutural plates are short, rounded, separated by a flat, straight median sinus. Insertion plates slit and crenulated. 16
242 LIOLOPHURA.
Anterior valve having 12 to 15 short, unequal, deeply striated teeth. Posterior valve triangular, flattened, with a callus in place of the insertion-plate. All of the apophyses (which are of a horny color) have a brown spot at the angle.
Length 19 lines, breadth 1 inch. (Q. & <?.)
King George Sound, S.-W. Australia (Port du Roi-Georges.)
Chiton georgianus Q. & G., Voy. de 1'Astrol., Zoologie, iii, p. 379, t. 75, f. 25-30.
This species is apparently still unknown in English and Amer- ican collections. It seems to resemble closely the L. incana of New South Wales, but differs, if we may trust Quoy's account, in the much shorter girdle appendages, which resemble " rounded tuber- cles " rather than unequal spines. The figure of a detached valve given by Quoy shows a forward wave of the tegmentum at the median sinus, more prominent than in any incamis before me, which scarcely show such a wave except on the second valve. The median valves of Enoplochiton niger, however, present an exactly similar sinuosity of the margin (compare figs. 24, 25, of pi. 52). The sinus, moreover, appears in Quoy's figures to be bridged by a lamina con- necting the sutural plates, a condition which does not obtain in L. incana. It is possible that the small variety mentioned by Quoy is more closely allied to the incana, or identical with it.
L. CURTISIANA Smith. PI. 24, fig. 6.
I am disposed to believe that CHITON CURTISIANUS Smith, which is described on p. 97 and illustrated on pi. 24, fig. 6 (figure enlarged and inverted), is a member of this genus; but as Smith called it an Ischnochiton, I included it in that genus provisionally.
L. JAPONICA Lischke. PL 53, figs. 41, 42, 43, 44.
Shell oblong, moderately elevated, arched, not carinated. Surface lusterless, generally much eroded and encrusted ; blackish, generally showing a wide light stripe on each side of the black dorsal stripe ; the wide girdle olivaceous, not distinctly barred.
The median valves are beaked; lateral areas hardly raised, sculpt- ured with concentric growth-wrinkles and a minute granulation, often lost by erosion. Central areas similarly sculptured. Thefonvnnl half or two-thirds of the lateral areas and the outer portion of the central areas is black-dotted by the numerous irregularly scattered eyes. Anterior valve sculptured like the lateral areas and closely studded with scattered black dots (eyes). Posterior valve depressed,
243
the miiero posterior and terminal, UMIIL: produced l.evond and above the p<Meri..r oaves.
Interior black. The sutural plates an- Mack both outside and within, and an- widely separated by a broad, deep, rounded *inu~. Head-valve with 8, 9 or 10, median valves 1 slit; teeth short in front, longer at the sides, deeply pectinated outside. Posterior valve having a broad flat crescentic callus in place of the insertion- plate.
Girdle very broad, densely clothed with short, obtuse black-brown spines, tipped with whitish (fig. 43.)
Length 50, breadth 20 mill, (measurements not including girdle.)
Japan, at Enoshima (F. Stearns) ; Oosima (' Challenger ') ; Nag- asaki (Lischke.)
Chiton japonicus LISCHKE, Malak. Blatter, xxi, p. 22 (June, 1873) ; Japonische Meeres-Conchylien iii, p. 71, t. 5, f. 8-11. — Maugeria japonica DKR., Index Moll. Mar. Jap., p. 158. — Acantho- pleura (/) incana HADDON (in part), Challenger Polyplac., p. 25. Not Ch. inconus Gould. — Ormthochiton caliginosus CPR., MS. (spec- imen described from China.)
? Chiton De Filippii TAPPARONE CANEFRI, Zool. del Viaggio intorno al Globo del la R. Fregata ' Magenta,' Malacol., p. 77, 1874.
Distinguished from L. incana by the uniform black color of the inner layer or articulamentum.
The typical japonica (pi. 53, figs. 41-44) has a broad girdle, •densely clothed with spinelets which are nearly or quite cylindrical, and are about equal in size over the entire area of the girdle. There are usually some dusky bars, especially toward the ends ; and the individual spinelets are dark brown, tipped with light brown or cream-white.
Var. tessellata Pils. (pi. 53, figs. 45, 46) includes specimens agree- ing with the type in valve structure and coloring, but having the girdle much narrower, and conspicuously varied with alternate patches of white and scorched-brown or blackish. The individual spinelets are larger than in typical,/"/"""'"' Iinc^ vary much in size, being small toward the outer edge of the girdle, large and flattened toward the inner edge. Upon the light tracts the spine? are uni- colored white ; upon the dark tracts they are reddish-brown or blackish, unicolored or tipped with lighter.
L'4-l ONITHOOHJTON.
Specimens collected by Stearns are before me, from Enoshima, where the typical form also is found.
The type of Carpenter's unpublished Ornithochiton (/) caliginosus is shown in figures 41-45 of pi. 54. It was described from specimens in the Cuming collection from " China Seas," and C. B. Adams collection from Hongkong. I have no doubt of its identity with the L. japonica. The latter had not been published at the time Carpenter wrote his diagnosis.
Tapparone Canefri's note on Ch. defilippii is not sufficiently clear for me to quote it without the mark of interrogation ; for he com- pares with a species from Sydney which he calls Chiton piceus Gmel. But although he refers to Reeve, fig. 70, I am disposed to believe from his text, that what he really had from Sydney was lAolophura incana Old. In this case, there can be little doubt that his defilippii is a synonym of L. japonica.
L. LOOCHOOANA Broderip & Sowerby.
Valves subscabrous, the marginal areas radially granose. Girdle
leathery, granose above, the grains elevated. Length 18J, breadth
7| mill. A very pretty little Chiton, whose margin is covered with
small grains, resembling very short, blunt spines. (Brod. & Sowb.)
Shore of Loo Choo Is. (Belcher, Mus. Zool. Soc. Lond.)
Chiton loo-chooanus BROD. & SOWB., Zool. Journ. iv, p. 368 (Oct. 1828— Jan., 1829.)
This species is absolutely unrecognizable by the above descrip- tion, but it was perhaps a member of the genus Liolophura which the authors had before them. It is not mentioned or illustrated in the " Zoology of Captain Beechey's Voyage." See Gray's reference to these descriptions in the " Introductory Remarks," Zool. Beechey's Voy., p. 103.
Genus XIX. ONITHOCHITON Gray, 1847.
Onithochiton GRAY, P. Z. S. 1847, p. 65, 6S.— Onythochitont GRAY, /. c., p. 169 (type Ch. undulatus) ; Guide Syst. Dist. Moll. B. M., p. 184.— Ornithochiton CPR., in Dall, Proc. U. S. Nat. Mus. 1881, p. 284.
Valves exposed, polished, beaked, with indistinct lateral areas ; eyes present and disposed in a ray on the forward part of each lateral area and in numerous rays on the anterior valve. Interior porcellanous ; sinus denticulate, angular ; insertion-plates pectinated
i.NI I II'" Illl
outside, tliat of tin- first valve with N slits, median valves 1 slit; pos- terior valve depressed, triangular, with posterior terminal and mar- ginal inurro, the insertion-plate reduced to a low, smooth and narrow callus. Girdle leathery, rendered velvety by very minute chaffy hairs. Type 0. umfn/afnn Quoy.
This genus resembles Enoplochiton and Liolopkura in the char- acters of the tail valve. It differs from the former in the unsculpt- nred, porcellanous interior, much more delicate structure of the tail- valve callus and different type of girdle. Onithochiton differs from LiolopJwra in the texture both inside and out, the very different arrangement of the eyes, more delicate tail-valve callus, and in the characters of the girdle.
The species are distributed from the Cape of Good Hope to New Zealand.
Carpenter emended the name to " Ornithochiton " believing it to be derived from ornis, ornithos, in allusion to the resemblance of single valves to the conventional representation of a bird on the wing ; but if any Greek root was in Gray's mind it was probably Onychochiton rather than Ornithochiton.
Key to species of Onithochiton.
a. Lateral areas and anterior valve smooth or radially sculptured ; central areas smooth. b. Lateral areas smooth or with 4 or 5 low subgranose riblets,
undulatns. bb. Lateral areas closely sculptured with close, subgranose striae,
semisculptus.
-aa. Lateral areas having concentric sculpture ; central areas or pleura with for wardly-con verging sulci. '
b. Length of posterior valve from sinus to mucro distinctly less than half the valve's breadth, lyellii, quercinus, rugulosus,
[amicorum.
bb. Length of posterior valve from sinus to mucro half the valve's breadth.
c. Valves having a smooth dorsal triangle, maillardi.
cc. Valves having zigzag sculpture over the ridge, literatus.
O. UNDULATUS Quoy & Gaimard. PI. 55, figs. 14, 15, Hi.
Shell oblong, moderately elevated, the dorsal angle rounded, side- slopes nearly straight. Surface polished ; color either (1) olive-buff
246 ONITHOCHITON.
or olive-gray, becoming yellow toward the apices of the valves, each valve elegantly painted throughout with concentric olive or brown lines, and having a darker dorsal band ; or (2) olive-green at the sides, with a broad light triangle on the ridge of each valve, in the middle of which there is a stripe of rich chestnut or of green ; the whole concentrically lineolate with irregular green and cream-white lines.
The valves are beaked ; lateral areas but little raised, and either smooth or sculptured with 4 or 5 low, more or less obsolete, beaded radiating riblets ; and showing under a lens, a band of eye-dots near the front margin. Central areas smooth and polished. Anterior valve having obsolete radiating riblets, and rays of eyes, the eye- rays variable in number, width, and degree of coalescence, the individual eyes being very mutable in number and position. Pos- terior valve very shortly subtriangular, the distance from sinus to mucro being but little more than one-third the width of the valve's tegmentum.
Interior white, marked with reddish-brown under the beak in each valve. Sinus delicately toothed, deep and angular; sutural-plates higher toward the sinus than toward the outer edges of the valves- Anterior valve having 8 slits, median valves 1 slit ; teeth obtuse, closely and sharply pectinated outside and on the summits. Poste- rior valve having a narrow, slightly convex ridge in place of the insertion plate.
Girdle reddish or brown.
Length 25, breadth 16 mill. ; divergence 110°.
Length 27, breadth 14 mill.; divergence 110°.
New Zealand, at Bay of Islands (Q. & G.) ; Auckland to Dunedin (Hutton) ; Chatham Is. (Hutton.)
Chiton undulatus Q. & G., Zool. Astrolabe, p. 393, t. 75, f. 19-24. — REEVE, Conch. Icon., t. 16, f. 87, 90. — OnitliocMton undulatus ADS., Genera, i, p. 476, t. 54, f. 3. — Tonicia mtdulutn HUTTON, Man. N. Z. Moll., p. 114 (1880.;
The comparative breadth of this species is subject to considerable mutation, as well as the coloring and the development of weakly beaded riblets on the lateral areas. In some specimens these riblets are not perceptible. Occasionally the sides of some valves are uni- form greenish, lacking brown lines and angular white lines.
This species has been reported from Tasmania, but on insufficient authority.
oun ii<" m TON. - 17
Tin- sculpture in this form differs markedly from the Au-t ralian and S. AtViean species.
O. SEMI8CULPTU8 I'ilshrv, n. sp. PI. f,f), figs. 10, 11.
Sliell oblong, elevated, subangular, dark olive-green, having snowy angular lines and dots on the lateral areas, and closer, more regular transverse lines on central areas. Surface shining and xmooth onthe central ureas, closely and finely striated radially on the head valv /<tt< ral areas, the *trin- crowded and subyranose, about 12 in number on each lateral area. Interior white. Girdle narrow, brown.
Length 27 J, breadth 16 mill.; divergence about 95°.
Habitat un J: ic > a a.
This species resembles the stout, elevated, dark olive forms of 0. nmlnlatus, such as occur at Auckland, N. Z., in contour and colora- tion. It differs markedly from undulatus and all other known species in t<he sculpture of the lateral areas.
Figure 10 shows two half valves, the upper illustrating the color- pattern, the lower the sculpture.
O. LYELLII Sowerby. PL 55, figs. 1-7.
Shell oblong, moderately elevated, the dorsal ridge rounded or slightly subangular. Color extremely variable ; typically green at the sides, with a tessellated black or chestnut dorsal stripe in the middle of a pink-dotted area ; but other specimens are blotched with green at the sides with concentric creamy lines and a creamy area on the ridge of each valve, along which runs a band of dark chestnut spots often on a bluish ground. Occasional specimens have a large black blotch on the sides of some valves.
The median valves are beaked. Lateral areas a trifle raised, sculptured with rather uneven concentric shallow grooves with rather wide, flat interspaces ; near the front edge of each lateral area there is a narrow band of minute eye-dots. Central areas scut]>tnr«l at the sides with fine, close grooves (continued from those of the lateral areas) converging toward the ridge, where there is a narrow smooth dorsal band. Anterior valve having about 10 narrow rays of eyes, the spaces between sculptured with concentric grooves interrupted by the eye-bands into scallops having their convexity upward, terior valve broadly triangular, depressed.
Interior white with a crimson spot in the cavity of each valve. Sinus deep, angular, delicately subdenticulate. Anterior valve hav- ing 8, median 1 slit ; the teeth rather long, sharply pectinated out-
248 ONITHOCHITON.
side. Posterior valve having a smooth callus in place of the inser- tion-plate, separated from the eaves by a groove at each side.
Girdle leathery, closely clothed with microscopic down, clouded brown and whitish.
Length 42, breadth 20 mill.
Pitcairn Island, in small hollows, at low water mark (Cuming) ; Raine's Island, Torres Ste., under stones at low water (Ince) ; Wat- son's Buy, N. S. Wales, Australia, at very low tides (Angas.)
Chiton lyellii SOWB., P. Z. S. 1832, p. 26 : Conch. Illustr. f. 7.— REEVE, Conch. Icon., f. 12. — Chiton incii REEVE, Conch. Icon- no. 94, t. 16, f. 96 ; detail fig. 94. — Chiton puncticulatus REEVE, Conch. Icon., t. 13, f. 696 and description in part — Onithochiton incei ANG., P. Z. S. 1867, p. 223.
This species differs from O. maillardi in the narrower smooth dorsal areas, the less deep, less regular grooving of the lateral areas, and the shorter and broader posterior valve. It relations to the following species are not clear to me, as I have seen no authentic specimen of the latter.
Figs. 8, 9 of pi. 55 represent the C. incii of Reeve.
The Chiton puncticulatus of Reeve seems to have been founded on a specimen of this species and one of Pallochiton lanuginosus ; but Reeve's reference to the punctation seems to apply best to this form. In any case, the name is so ill-defined that it cannot in fairness be used.
O. QUERCINUS Gould. PI. 55, figs. 12, 13.
Shell small, depressed, slightly carinateand beaked, ovate, yellow- ish wood or oak color, clouded with olive or dusky slate color at the sides. Lateral areas scarcely raised, but distinctly marked by coarse longitudinal sulci, which are divided by a radiating furrow and sometimes more, and the two portions form somewhat of an angle with each other; central areas with faint, rugose, longitudinal lines toward the margin, and scattered punctures about the apex ; anterior valve checked with raised spaces formed by concentric and more distant radiating furrows, which become more numerous near the margin ; posterior valve with theumbo nearly terminal, so that the transverse ridge runs nearly parallel to the margin. Marginal ligament broad, yellowish, frosted. (Old.)
Length 22, breadth 15 mill.
New South Wales, Australia.
i . N 1 1 1 1 • M • 1 1 1 1 249
Chiton quern' n n< «.M... Pro< Nut. Hi-t. ii, p. ML'
(1846); U. S. Expl. Erped M.,11., p. .'{12, f. 437, 1870; <>ti:i Conch., p. 3. — C. (f)nitlnn'hitnn) >jii' GH i'. ()tiji, p. -42.
Closely allied to 0. /y< /// and O. /•»/;/ "fosus. O. RuouLoeuB Angas. 1M. :>:>, fig. 19.
Shell elougately ovate, a little narrowed in front, raised and car- inated, pale yellowish-brown, the central areas of the valves faintly spotted with olive, the outer edges bordered with green, upon which and extending inward are concentric waved bands of olive brown darker at the margin; lateral areas not raised, divided from the dorsal areas by radiating nodulous ribs, transversely rugosely, costate ; dorsal areas finely longitudinally ridged ; mantle brown, variegated with ash-color and clothed with very minute chaff-like scales- (Aug.) Length 16 mill.
Port Jackson, Australia.
Onithnclnton rugnlosns ANG., P. Z. S. 1867, p. 115, 223, t. 13, f. 29.
Carpenter gives the following notes upon the type specimen : Shell broad, the valves much beaked, dorsal ridge acute. Mucro terminal. Jugal area scarcely distinct, smoothish ; central areas having about 16 nearly longitudinal, jagged wrinkles, nearly meet- ing over the jugum. Lateral areas very sharply rugose, much more so than in the other species, the rugse about 12, not developed in young shells, very irregular, swelling into granules especially «>n the diagonal lines and sutures. Anterior valve having 8 lines of black dots, with two additional, indistinct ones. Inside whitish with a brown spot in the cavity ; posterior valve having the mucro absolutely terminal, the insertion-plate planed off. Anterior valve having 8 slits; teeth very finely rugose; sinus deep, flat, tolerably broad, with about 20 fine teeth. Girdle covered with minute hairs.
Length 16$, breadth 12 mill.; divergence 125°.
O. AMICORUM Baird. PL 54, fig. 46.
Shell rather elongated, elevated, with acute dorsal ridge. There is a line of reddish-brown color along the dorsal ridge, and one or two others along the sides.
Lateral areas much elevated, with very nodulous wrinkles, two or three irregularly concentric ; these are partly on the diagonal and sutural ribs, with others intercalated. Central areas with about '2'2 slightly irregular riblets, nearly longitudinal, but bending toward the
250 ONITHOCHITON.
middle, the interstices very narrow. Anterior valve having about 20 radii, much smaller than those of the lateral areas, but toward the sutures becoming coarser than those of the lateral areas. Poste- rior valve depressed, the mucro subterminal.
Interior: anterior valve having about 9 slight slits, not corre. spending to the outside dots. Central valves with 1 slit ; teeth striated outside and at the broad, but sharp edge. Eaves planed off, scarcely grooved. Sinus broad, deep, with about 14 denticles.
Girdle stout, with shelly spines, exactly like magellanicus, prin- cipally whitish, irregularly tessellated with dark. (Cpr., from type.) Length 18, breadth 10 £, divergence 90.°
Nine or Savaye Island, Friendly Group (Brenchlev.)
Chiton ( Onithochiton) amicorum BAIRD, in Brenchley's Jotting* during the Cruise of H. M. S. 'Curacoa' among the South Sea Islands, in 1865. London, 1873, p. 445, t. 40, f. 7.
The generic position of this species is uncertain, but could be readily ascertained by an examination of the type, which is, we believe, in the British Museum. It is probably either an Onithochiton^ a Liolophura or a Plaxiphora. Baird's original description is as follows: "Shell ovate, nearly equal at each extremity; mantle margin covered with numerous chaffy-looking scales, first valve larger than any of the others, marked with numerous granular lines ; central valves strongly striated, lateral areas with 2 or 3 granular lines ; last valve small and striated. A line of a red color runs along the top of all the valves, whilst "one or two others run along the lateral areas. Length 8 lines, breadth 5J lines."
O. MAILLARDI Deshaves. PI. 55, fig. 20.
Shell oblong, elevated, the dorsal ridge roundly angled, side- slopes nearly straight. Surface shining ; color pale buff, with a nar- row orange-tinted or brown triangle at the ridge of each valve, several dark -green spots along each diagonal slope, the lateral areas and head valve with concentric green-olive sometimes dark brown lines.
Median valve beaked, the lateral areas somewhat raised, having near the front margin a narrow radiating band of eye-dots, the width of the band greater on the hinder valves; sculptured with longitu- dinal grooves corresponding with the dark color-lines, sometimes irregular or branching; and continuing upon the diagonal slope. Upon the central areas these grooves become much more delicate,.
<>M I II... in I
closer, M>D Vtfging tOWftrd tin- dorsal riil^r. and oftni /igzagged ; the median triangle of the central arras >inooth. A ntrrior valve having 8 narrow rays of ryes, i.rra-ionally with ,-onie eye- >eatt« red between along the lower margin ; the intervals between the eye-rays sculpt- ured with sulei forming short arcs of concentric grooves. Posterior valve depressed, triangular; //••« /on/tit from sinus to ///'• //".iterior terminal inncro briny one- half the greatest breadth of its tegmentum.
Interior white, with a large spot of rich brown in each valve. Sinus delicately toothed, wide and deep. Anterior valve having 8 slits, median valves 1 slit ; teeth finely and sharply pectinated out- side. Posterior valve having a smooth ledge of callus in plate of the insertion-plate, flat behind, rounded at the sides. Eaves narrow, grooved, solid.
Girdle fleshy-brown, leathery.
Length 24, breadth 15 mill.; divergence 110°-115°.
Mauritus and Bourbon (Reunion.)
Chiton maillardi DESH., Moll, de File Reunion, p. 38, t. 5, f. 14. — Chiton (Toniciaf) maillardi MARTENS, in Mobius' Reise nach Mauritius, p. 300. — Ornithochiton maillardi CPR., MS. — Ornitho- chiton sp., MOSELEY Quarterl. Journ. R. Mic. Soc. xxv, p. 54, t. 5, f. 4-7.
O. LITERATUS Krauss. PI. 55, figs. 21, 22, 23.
Shell ovate, convex ; brown, spotted with whitish and having a whitish longitudinal band ; closely silicate. Interior white, brown- ish-violet in the middle. Anterior valve lunate, convex with undulating grooves ; posterior valve triangular, depressed, sculptured with angular grooves; intermediate valves sinuated in front, rounded at the sides, undulately and angularly grooved. Girdle rufous-brown, leathery, velvety.
Length 12, breadth 8 lines. (Krauss.)
Natal.
Chiton literatus KRAUSS, Die Siidafrik. Moll. p. 36, t. 3, f. 6.
I have not seen this secies, which is evidently quite distinct, although allied to 0. maillardi. The central areas have angular or zigzag grooves; the lateral areas are not raised, and are sculptured with wavy grooves. The back is not carinated. Insertion plates as usual in the genus.
252 ENOPLOCHITON.
Genus XX. ENOPLOCHITON Gray, 1847.
Enoplochiton GRAY, P. Z. S. 1847, pp. 65, 69, 169.
Valves exposed, of a uniform dark brown or chocolate color out- side and within ; the lateral areas and head valve irregularly studded with extremely minute eyes. Interior minutely laminated and punctate in a peculiar pattern ; sinus deep, denticulate. Inser- tion-plates of anterior and median valves slit into teeth and sharply pectinated outside. Tail-valve having the mucro posterior and terminal, and inside with a flat ledge of callus in place of the lack- ing insertion-plate. Girdle fleshy, bearing extremely broad and short, blunt, separated striated scales.
The single species comprised in Enoplochiton resembles the larger Onit/iochitons in being polished and sculptured with wavy impressed lines (when not eroded) and also in the denticulate sinus, as well as in the structure of all the insertion-plates. It differs from Onitho- chiton in the peculiar texture and color of the valves, the sculpture of the interior and the structure of the girdle.
The eyes in this genus are extremely minute and oval instead of round. The megalopores and micropores are arranged in vertical lines (pi. 52, figs. 27, 28). The valves resemble those of Mesotoinura in most respects, excepting the tail valve, which is that of Onitho- chiion.
E. NIGER Barnes. PL 52, figs. 22-29.
Shell oblong, convex, the valves thick and dark brown outside and within. Surface shining when perfect, but generally eroded and dull.
The valves are strongly beaked, and generally much eroded*; but when not too much worn the sculpture is as follows : lateral areas marked with undulating longitudinal impressed lines ; central areas having a series of short impressions in front of each diagonal rib, and an impressed V on the ridge of each valve ; anterior valve hav- ing concentric wavy grooves ; posterior valve much depressed, with posterior terminal mucro ; sculptured like the median valves.
Interior seen under a lens to be sharply, densely laminate in front of the valve callus, punctate on the sutural plates and behind the valve-callus (fig. 25). Sutural and insertion plates of median vulves thick, tending forward; sinus broad, rounded or angular, denticulate; anterior valve having 9 slits, median valves 1 slit; teeth long, deeply, shaq^ly and closely pectinated outside. Posterior
ISCIIN'M HI I"M I' 1 .
valve having tin- inticro projecting beyond the narrow eaves; inser- tion plate obsolete, reduced to a callous ridge, flattened behind, rounded at tin- side.s and pectinated outside where it joins the sutural plates.
Girdle fleshy, bearing numerous wide, short, blunt, striated, sepa- rated scales (fig. 29, a young specimen) ; the interstices between the scales covered with a velvety pile.
Length 75-80, breadth 35-40 mill.
Peru (Capt. Ridgeley) ; Coquimbo Bay (Frembly) ; Valparaiso (U. S. Expl. Exped.)
Chiton niger BARNES, Amer. Journ. of Science and Arts, vii, p. 71, t. 3, f. 3 (1824).— Enoplochiton niger GRAY, P. Z. S. 1847, p. 69. — Chiton coquimbensis FREMB., Zool. Journ. iii, p. 197, t. 16, f. 2 (1827).— SOWERBY, Voy. 'Blossom' Zool., p. 149, t. 40, f. 6.— REEVE, Conch. Icon., f. 22.
The entire substance of the valves is colored in this remarkable species. Specimens as well preserved as the individual figured are not common ; but so peculiar is the entire shell that it may readily be recognized, however eroded.
This species like Acanthopleura spinifera, lives upon the rocks between tides in situations exposed to the full force of the surf. In fig. 27 a portion of the surface of a valve is drawn magnified, show- two eyes, megalsesthetes and micrsesthetes ; fig. 28 represents a por- tion more highly magnified, showing two megalsesthetes and the accompanying micrsesthetes.
Family ISCHNOCHITONID^.
A number of genera belonging to the Ischnochitonidce were omitted by me in my treatment of it in parts 1 and 2 of this volume, in deference to the views of Carpenter, who grouped them with Acanthopleura and its allies. A more profound study of this and related families, enables me now to see traits of relationship unknown at the time the synopsis on pages 23, 24, 25 was prepared, and there- fore to group the genera more naturally than was then possible.
Subfamilies of Ischnochitonidce.
CALLISTOPLACINJE, in which the slits of the anterior and inter- mediate valves correspond in position to radiating ribs on the exte- rior. (See p. 259.)
254
I8CHNOCHITOMN 1 -DINOPLAX.
i, in which there is apparently no such relation between slits and external ribs.
This last subfamily includes the majority of species, and a consider- able number of genera ; and while there are still some obscure points, the light cast by what we already know of their morphology is suffi- cient to show us the approximate paths of generic descent, the genera falling into three main groups, as shown in the diagram.
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Ischnochitoninse
Callistoplacinse
It will be noticed that Leptoplax and Spongiochiton are not included. These genera belong to the Acanthochitidaz. Moreover, it must be remembered that Trachyradsia is a synonym of Stereochiton (see p. 52) and part of Trachydermon belongs to the Tonicelloid branch. These groups were erroneously placed in the text.
The following genera belong to the Chudopleuroid branch of Ischnochitoninae and should have been inserted after the genus Chcetopleura (p. 27.)
Genus XXL DINOPLAX Carpenter, 1882.
Dinoplax CPR. MS., in DALL, Proc U. S. Nat. Mus. 1881, p. 284, 287 (Jan. 20, 1882).— Acanthopleura (in part) GRAY.— Chwtopleura (part) Sur i n. I:\VMR MI.— r/,,7o» s. s. (in part) ADAMS, Gen. Rec. Moll, i, p. 474, 475, not of Linn.
Valves heavy, exposed, the lateral areas high ; teeth of insertion sharp, smooth, those of the posterior valve directed forward; slits of
anterior \alvr not rorn^|.ondin_r t<» i-xtrrnsil rilis. Posterior luiriii'i the vnici". }n>*teri'n-. Suitttal plafat fn-nml/i/ imitxl across the sinus. < iinllr thick, lent licry, with minute Imm'hes of delicate sjnne- lets scattered upon it.
The position assigned by Shuttleworth to the type of this genus was not. tar from correct. The Ischnoid insertion-plates, solid eaves and the leathery spiculose girdle are characters strongly binding C. <ji<i<i.< to ( '/nrfttjtlfura. Upon parting the valves, however, we notice that the macro in C. gigas is situated toward the rear, and the [in- terior teeth are thereby thrown forward, as in Pallochiton ; the sutural plates are united by a brown "keystone" filling the sinus somewhat as in Endoxochiton (p. 192) ; and the spicules of the girdle are gathered into little bunches different from any other Chiton. The valves, too, are remarkably solid. This combination of char- acters seems sufficient for the establishment of the genus Dinoplax, the position of which I take to be near Pallochiton.
D. GIGAS Gmelin. PI. 57, figs. 21-32.
Shell oval, large, ponderous and strong, elevated, obtusely angled. Surface lusterless, eroded, ash-white in color with some brown smears, when adult; the young being prettily streaked or mottled with chestnut and bluish on a light ground.
Median valves not beaked ; lateral areas very much elevated, radially striated in young shells and upon the outer edges of adults ; central areas closely and finely foveolate in the young, and on the protected front edge of adult valves. Anterior valve elevated, its surface similar to the lateral areas. Posterior valve depressed but roof-shaped, the mucro posterior, the slope behind it nearly vertical.
Interior whitish, flesh-colored on the sutural plates and marked with brown at their bases; having two broad chestnut rays behind. Sutural plates wide, connected across the sinu* by a broad key-stone shaped lamina. Anterior valve having 8-10, central valves 1, pos- terior valve 8-10 slits ; teeth acute, smooth, those of the posterior valve rather stumpy, wedge-shaped, directed forward. Eaves solid.
Girdle fleshy, strong, blackish, beset with numerous tiny bunches of minute spinelets (fig. 31.)
Length 70, breadth 45 mill.
Length 100, breadth 56 mill.
South Africa, at Table Bay, Natal, Port Elizabeth and Algoa Bay.
Chiton tnaj-imu* a Promontorio Bomc Spei CHKMNITZ, Von einem Geschlechte vielschalichter Conchylien mit sichtbaren Geleuken,
256 PALLOCHITnN.
fig. 10 (1784). — Chiton maximus *eu pipof CHSHHITZ, Com-hyl. Cab. viii, p. 292, t. 96, f. 819 (good), 1 785.— Chiton gigas GMEL., Syst. Nat. xiii, p. 3206 (1788).— SPENGLER, Skrivter af Naturhistorie- Selskabet, iv, p. 101 (1795).— WOOD, Gen. Conchol., p. 12 (1814). — BRUG., Encyclop. Meth., t. 161, f . 3 (copied from Chemnitz). — LAMARCK, An. s. Vert, vii, p. 490. — BLAINVILLE, Diet. Sc. Nat. xxxvi, p. 543. — REEVE, Conch. Icon., f. 65. — KRAUSS, Die Siidafrik. Moll., p. 40, t. 3, f. 3 (young).— H. & A. ADAMS, Genera Rec. Moll, p. 475. — SOWB., Marine Sh. of South Africa, p. 50. — Chalopleura gigas SHUTTLEW., Bern. Mittheil. 1853, p. 67. — Acanthopleura gigas GRAY, P. Z. S. 1847, pp. 68, 169.— Chiton siibgigas BLAINVILLE, Diet. Sc. Nat. p. 543 (young specimen). — Dinop lax gigas CrR., MS. — Chiton albus BARBUT, The Genera Vermium of Linnseus, Pt. 2d. (London, Mar. 2, 1788), Vermes Testacea, p. 8, t. 1, f. 1 (not Ch. albus Linn.)
The dull, corroded aspect of this large species seems to be invari- able in adults. The strongly raised lateral areas, black, leathery girdle, and peculiar contour render it very distinct in appearance. The figures of Chemnitz are most characteristic, but that it is impos- sible to quote him as authority for the name must be admitted. Although the bibliography of this species is rather extensive, the only references worth reading are Chemnitz, Krauss and Carpenter.
Rochebrune has cited this species from the strait of Santiago, Cape Verde Archipelago (Nouv. Arch, du Mus. iv, p. 239, 1881), but his paper contains such a host of erroneous locality citations that one hesitates to accept any of them without confirmation.
Genus XXII. PALLOCHITON Dall, 1882.
Hemphillia CARPENTER JfSS., type H. lanuginosa Cpr. ^fSS. Not Hemphillia Bland & Binney. — Pallochiton DALL, Proc. U. S. Nat. Mus. 1878, p. 297 (dentition described, but no generic diagnosis, and founded on the undescribed species P. lanuginosiis. Feb. 13, 1879).— Pallochiton DALL, Proc. U. S. Nat. Mus. 1881, p. 283, 287 (Jan. 20, 1882).—? Arthuria CPR.
Valves exposed, solid, the anterior and median having sharp insertion teeth slightly roughened outside ; slits of anterior valve not corresponding to anything in the external sculpture ; tail valve having the mucro at the posterior end, the teeth sharp and all strongly directed forward ; eaves solid ; sinus notched at sides. Girdle leathery, with a few deciduous hairs, but no pores.
PAI.I CM IN i' 257
This J^MIIIS rln-rly rrsrinldrs in sculpture a- well as st ruct ural characters, ('/nrtoj>/t'nr<t Shuttlow.; dilli-nuL: only in tin- posh-rior position of the macro and the consequent throwing forward of tin-, tail-valve insert ion-tec! li, — characters of no great importance. Th«- slits correspond in position to nothing in the external sculpture. The girdle is decidedly like Chcetopleura, ln-in«r vn-y sparsely hairy (or smooth) and lacking all appearance of pores.
P. LANUGINOSUS Carpenter, n. sp. PL 56, figs. 1-11.
Shell oblong or ovate, rather elevated, carinated, the side-slopes nearly straight. Surface lusterless, color very variable ; sometimes dull brown or purplish-brown ; sometimes green along the ridge and purple or lilac dotted with black or olive at the sides ; or having the sides of some valves scarlet or even snow-white.
The median valves are rather acutely beaked in the young, beaks eroded in olcl specimens. Lateral areas but little raised, sculptured with gem-like pustules scattered irregularly on a flat (microscopic- ally puncticulate) ground ; the pustules often few, rarely wanting on some valves ; central areas sculptured with many closely beaded longitudinal threads, which converge slightly at the ridge, and diverge toward the outer sides of the valves ; on the second valve they diverge at the ridge. Head valve pustulose like the lateral areas. Tail valve (fig. 11) much depressed, the mucro at the posterior end ; anterior area wide, sculptured like the central areas ; posterior area very narroiv, vertical, sometimes pustulose.
Interior bluish-white, darker at jugum and posteriorly ; rarely flesh or pink tinted. Sutural plates very broad; sinus narrow, deep, angular and notched at the sides. Anterior valve having 8-9, central 1 slit, the teeth long, sharp, a little rugose outside ; posterior valve having 10-11 slits, the teeth chisel- shaped, strongly directed forward, smooth and rather sharp. Eaves of anterior and median valves narrow, of posterior valve wider, solid.
Girdle rather fleshy, leathery when dried, somewhat encroaching at the sutures, and smooth or clothed with sparse delicate hairlets.
San Diego, California ; Todos Santos Bay to Pta. Abreojos, Lower Cal.
Hemphillia lanuginosa CPR., MS. — Pallochiton lamtfjinofiiis Cpr-. BALL, Proc. U. S. Nat. Mus. 1878, p. 297, pi. 3, fig. 21 (dentition). — Chiton (Pallochiton) Imimjinosa (Cpr.) Dall, ORCUTT, Proc. U. S. Nat. Mus. 1885, p. 544. 17
258 PALLOCHITON.
?? Chiton pwuticukstui REEVE, Conch. Icon., Chiton, no. 69 (in part.)
The posterior terminal mucro, leathery girdle, and beaded sculpt- ure well distinguish this species. The coloring of some specimens (such as those from S. Ignacio Lagoon, Lower California, represented by fig. 1, 6) is of exquisite delicacy. Old individuals generally lose the pustules of the surface except at the base of the valves. One of Reeve's illustrations (fig. 69a) is said to represent a specimen of this species ; but as the other (fig. 696) is certainly an Onithochiton, and as the description indicates that rather than the Pallochiton, I have preferred to retain Carpenter's name for this species.
A peculiarity of coloring not mentioned in the description is the vertical white stripe extending down the posterior slope from the mucro of the tail valve. In the great number of individuals examined by me I have never found this lacking.
Section ARTHURIA Carpenter, 1882.
Arthitria CPR. MS., in BALL, Proc. U. S. Nat. Mus. 1881, pp. 284, 287 (Jan. 20, 1882). Type A.filosa Cpr.
Shell thin ; valves waved ; mucro posterior, produced. Insertion plates acute, smooth, projecting forward in the posterior valve ; sinus flat, laminate, smooth. Girdle leathery, smooth or downy. (Cpr., MS.)
This section seems to present no characters separating it from Pallochiton. I have not seen the type and only species, and it has not been figured. Comparisons should be made with Pallochifon lanuginosus Cpr.
P. i ILOSUS Carpenter, n. sp.
Shell oval, subelevated, the dorsal ridge acute; mucro posterior, hardly terminal, elevated on a strong marginal ridge, the outline in front of it concave. Intense or pale olivaceous.
Valves delicate, rounded at the margin, making deep sutures. Central areas haiing about 13 distant, beaded subparallel threads on each side, sometimes obsolete, and closer and subacute upon the ridge. Lateral areas moderately defined, and together with the end valves having irregularly scattered rounded granules.
Interior: anterior valve having 10, central 1, posterior valve 9-
10 slits ; teeth of the posterior valve solid, acute at the edge, strongly
ned forward, the slits sloping; the other valves having very
acute teeth. Kaves of p..>trrii>r valve wide, flat, sul»pongy; of other valves moderate, hardly Lrn>oved. Sinus narrow, dccj., hardly toothed, slit at the sides, at t he jmiet ion of the sutural plates.
Girdle leathery, smooth or most minutely and closely downy.
Length '2\l hreadth 16* mill; divergence 110°-120°.
Habitat unknown.
Arthur in filosa CPR. MS. and in DALL, Proc. U. S. Nat. Mus. 1881, p. 287 (name only). Types in Mus. Cuming, nos. 23, 38.
Carpenter's description is given above. He remarks :
" This shell has the tail plate of Nuttallina, but the other valves more resemble Chcetopleura or Tonicella. It is known externally from Nuttaffina by the nearly smooth girdle ; but would hardly be distin- guished from Omithochiton except by the regular articulation of the insertion-plates. In the Ischnoid genera, the posterior profile from the mucro is often concave ; in this the anterior. In consequence of the great projection of the beak, both in Nuttallina and Arthuria, the posterior teeth appear plumulate rather than fissured ; a char- acter also seen in Callistochiton. The terminal valve in both the specimens examined are exactly alike in color as well as markings ; but the central valves in one specimen are of a much lighter color, with more delicate and well developed sculpture."
Subfamily CALLISTOPLACIN^E.
Ischnochitonida3 in which the slits of the anterior valve correspond in number and position to the radial ribs of the exterior. Teeth generally thickened at the edges of the slits.
In this subfamily, which seems to be a natural division, may be placed a number of genera widely scattered in Carpenter's scheme. These genera fall into three groups, or branches, lettered a, aa, and aaa in the following table. The first of them seems to have affinities with the typical Ischnochitons, the second slightly resembles the Acanthochitidve, and the third may be somewhat allied to the Mopaliidce.
The number of anterior slits sometimes exceeds the number of external ribs, so that the subfamily diagnosis must not be taken too literally. The plan of structure is sufficiently obvious; but exuberant Nature knows nothing of absolute adherence to rules.
260 CALLISTOCHITON.
K< y to genera of Callistoplacince.
a. Surface of valves having strong radial ribs ; girdle densely
clothed with imbricating scales, CALLISTOCHITON.
aa. Surface of valves granulated or pebbly ; girdle not densely
imbricated with scales.
b. Anterior valve with more than 7 slits ; sinus very spongy ;
imicro posterior, NUTTALLINA.
bb. Anterior valve with 5 slits; mucro subcentral, not posterior,
CRASPEDOCHITON. ANGASIA. aaa. Surface of valves wrinkled or ribbed ; girdle naked except for
hairs or corneous spines.
b. Valves having very strong radial ribs; girdle naked, with
sutural tufts, CALLISTOPLAX.
bb. Valves not very strongly sculptured ; girdle tough, with
corneous curved spine-like processes, CERATOZONA.
Genus XXIII. CALLISTOCHITON Carpenter, 1882.
Callistochiton CPR., Table of Regular Chitons, 1873.— DALL, Proc, U. S. Nat. Mus. 1881, p. 283, 289, 290 (Jan.-Feb., 1882).— Callo- chiton (in part) H. & A. Adams, and of CARPENTER, P. Z. S. 1865, p. 276, not of Gray.
Valves conspicuously sculptured ; the insertion-plates short, smooth or nearly so, festooned, being curved outward at the ribs and slit there, thickened outside at the edges of the slits, the latter corresponding in position to the ribs of the outer surface. Sinua squared. Mucro median or post median, generally depressed. Girdle poreless, densely clothed with minute striated or smooth scales. Type, Chiton pukhellw Gray.
This genus differs from Ischnochiton in the peculiar insertion-teeth, which are curved into the ribs as if festooned, in the relation of the slits to the external ribs, and in the tail valve, which is often peculiarly humped.
The species though not numerous, are widely distributed, Aus- tralia, Red Sea, Japan and the Gulf of Mexico together furnishing about half, the rest being from the western coast of the Americas, from southern California to northern Chili.
Nearly all of the species have the lateral areas strongly bicostate and granose; the end valves have strong ribs, the number of which
« \ i.i .1-1 n( inioN. 261
is le-< valuable :is :i specific cli;ir:ictcr than one would at first suppose, on account of their tendency to increase by splitting. When a rib splits, an additional slit appears in the insertion-plate; so that this character also is lamely vitiated.
The best characters for distinguishing species are the sculpture of the median portion of the central areas, and the contour of the tail valve ; the profile of the latter being especially characteristic and constant.
The following notes from Carpenter's MS. apply more especially to the more typical forms : " It is quite possible that in their earlier stages these curious shells resemble Ischnochiton ; but as they pro- ceed toward maturity, while they spread naturally in the seven ante- rior valves, the posterior is simply raised a tier higher ; consequently, in the adult, the posterior part of the tail plate resembles a closed fist outside; and within the teeth and eaves are very broad and blunt. There is an approach toward the throwing forward observed in Acanthopleura. In Ischnochiton, whatever be the external sculpt- ure, the row of teeth follow the same oval line, and the incisions do not correspond (except by accident) with the external ribs ; whereas in Callistochiton the tooth line is elegantly scalloped in and out of the hollows of the ribs.
" In general the incisions are in the centre of each rib, and the plates are there propped outside, as in Callochiton ; but sometimes a separate keystone (as it were) is let into some or all of the arches on the terminal valves. The genus appears to culminate on the Cali- fornia coast, and reaches its greatest development in C. palmulatus ; in which the posterior valve displays the further peculiarity of each tooth being broken up into a number of fingers, each fluted, and so arranged that the inner margins form a semicircle while the outer present the scalloped curve of the genus. The valves are peculiarly solid and are easily detached from the thin and narrow zone. The sinus has always a lamina, which is generally marked off by slits from the sutural lamina, but is scarcely ever dentate. Two of the species have minute, smooth scales."
Key to species of Callistochiton.
One species, C. heterodon Pils., has pectinated teeth like a typical Chiton, and it is placed in this genus with much doubt ; the others may be tabulated thus :
262 CALLISTOCHITON.
a. Central areas having a pitted or net-like pattern toward the beaks.
b. Mucro posterior, not depressed, tail valve with 7 ribs;
scales smooth, pulchellu*.
bb. Mucro subcentfal, the slope behind it concave, scales
striated, shuttleivort/i Inn n*.
bbb. Mucro subcentral, tail valve rapidly sloping backward
from the front margin ; eaves narrow ; scales striated,
(inilquus.
aa. Central areas smooth in the middle, decoratus.
aaa. Central areas sculptured throughout with parallel lira.
b. Posterior area of tail valve swollen above the anterior area, palmulatus.
bb. Posterior area not higher.
c. Mucro posterior ; riblets converging on ridge,
crassicostaius.
cc. Mucro subcentral, riblets not converging on ridge. d. Profile of tail valve convex, mucro obtuse,
infortunatus.
dd. Profile of tail valve rapidly sloping 'back- ward from the front margin, mucro flat,
gabbi.
The species elenensis and expressus from western Middle Amer- ica, and adenensis from the Red Sea, probably belong in the last section of the above table, but I have seen no specimens. C.jacob- &U8 of Gould also belongs near infortunatus, probably.
C. PALMULATUS Carpenter, n. sp. PI. 58, figs. 7-16.
Shell similar to C. pulchellus, but more flattened, the dorsal ridge acute; mucro subcentral, depressed, the posterior area strongly swollen; sculpture stronger; central areas having about 10 sub- parallel acute line on each side, pectinatiug the sutures, interstices deeply cancellated; lateral areas having two strong ribs bearing strong tubercles, the sutures dentate, interstices deeply punctate. Anterior valve having 11 ril>>, of which the outer two are joined; posterior valve 7 very strong ribs bifurcating behind.
Interior: anterior valve having 11 slits, central 1 slit, the teeth normal ; posterior valve having 26 slits, the teeth crowded, minute, palmate. Eaves very strong; sinus small, strongly laminate, the
• M.i.isTorm i' W,
lamina di-eply slit on each side, (iirdlc imbricated with striated scales.
Lcnirth 1 1 !, hrradth 7-1 mill.; divergence l-'if)0. (Cpr.)
N/rf. n.irbnra (Cooper, Cal. State Coll. no. 1077) ; Monterey (Can- field, coll. Cpr.)
The above description is quoted from Carpenter's MS. He gives the following additional notes: " This species with a general resem- blance to pulchcllns, is known outside by its stronger sculpture, flat- tend anterior and tumid posterior valve ; and by its sharp back with flattened sides. It is one of the most remarkable peculiarities of Chitons that they are so particular in special adornment of their tails, while their heads are covered with very uniform plates. In this species this peculiarity culminates. Not only the radiating and fur- belowed arrangement of the teeth presents the greatest differentiation yet observed in a Chiton, but the fluting of each individual finger- like tooth adds special beauty to the complex pattern."
Figures 7, 8, 13-16 are from drawings prepared for Dr. Carpenter ; fig. 12 represents the tail valve of a typical specimen before me, for comparison with that of the following variety.
Var. MIRABILIS Pilsbry, n. v. PI. 58, figs. 7, 8, 9, 10, 11.
Shell oblong, elevated, the back angular, side-slopes convex. Surface lusterless, dull brownish, the lateral areas and end valves blackish.
Valves not beaked; the lateral areas widely separated by the eroded beaks, greatly elevated, each split by a deep median sulcus, the two ribs thus formed bearing coarse transverse grains. Central areas sculptured with about 15 narrow longitudinal cords, parallel at the dorsal ridge except on the second valve in which they diverge forward ; the interstices wider than the cords, and finely latticed across. Anterior valve having 9 stout radiating ribs, strongly granose, and with the exception of the two outer ones, they are generally not bifid. Posterior valve much higher than the anterior, the mucro somewhat in front of the middle, the area behind it enormously developed, > I r<if,,( and convex, sculptured with 4, 5 or 6 primary stout ribs, each of which splits into two ; the two outer ribs are broader, and split into several riblets.
Interior bluish-white; sutural-lamime slightly connected across the squarish sinus. Anterior valve having 9, central 1, posterior valve 22 slits ; teeth short, somewhat roughened. Eaves broad, calloused.
264 . CALLISTOCHITON.
Girdle narrow, thin, covered with very densely imbricating minute deeply striated scales (fig. 8.)
Length 16, breadth 7 mill.
San Diego, California.
The form described above was known to Dr. Carpenter by one perfect though worn specimen and a single worn posterior valve. He gives (MSS., p. 134) the following notice of it, under C. palm- iilutus.
"? Variat. : ar. centr. liris utr. lat. 16-18; v. post. 5, bifurcatis; mucro usque ad dimidium totius altitudinis depresso ; sinus lamina vixfissata. Long. 15, lat. 7*, diverg. 110°."
These lines give the essential points of difference between this variety and the typical form, viz., the more numerous side riblets of the central areas in a shell of the same width, the greatly elevated posterior area of the tail valve, the greater proportionate length and altitude of the shell and the smaller angle of divergence. The value of these characters for distinguishing the two forms remains to be seen, and can only be ascertained by the examination of abundant material. That this form is not merely a fully grown (ephebic) or old (geroutic) state of the original palmulatus is shown by the com- parison of small specimens, not exceeding in length the typicalpafa- 11 lat us before me.
The enormously swollen posterior area of the tail valve separates this from all other species. In several additional details the form differs from C. crassicostatus, notably in the strongly two-ribbed lateral areas, the more numerous ribs of the anterior valve, the riblets of the central areas being parallel at the ridge except on the second valve where they diverge ; whilst in C. crassicostatus they converge forwardly on all of the median valves. The seventh valve of this form is distinctly narrower than the other valves, being crowded by the unusually developed tail-valve.
The type specimen is in the collection of the Academy.
C. CRAS3ICOSTATUS Pilsbry, n. sp. PI. 58, figs. 1, 2, 3, 4, 5, 6.
Shell oblong, elevated, the dorsal ridge very obsoletely angular, side-slopes arched. Surface lusterless, green or brown.
Valves not beaked, the lateral areas extremely in-ominent. mien ///// granu/'it* /, the concentric riblets being cut by one or several radiat- ing grooves. Central areas having strong longitudinal bars, con- verging \-like on the indge (even on the second valve], the intervals
CA l.USTi H II II' >\ .
\ery oloeelj and finely latticed across. Anterior v<t/w Ham very stro in/ ril>.<, cadi divided by a shallow median gTOOY6. I'oste- rior valve elevated, having ///' macro directly over the }> '/.'/',
//' hinder ttrcn not h'njln-r than the arco in front of it; posterior slope vertical, convex, sculptured with live very strong, deeply separated ribs, which are i^rauose above, and subdivide into several riblets each toward the lower margin.
Interior bluish-white ; sutural-plates slightly connected across the rounded sinus. Anterior valve having 9, central valves 1, poste- rior valve 13-20 slits ; teeth short, rather sharp and smooth, hardly projecting below the eaves, thickened along the slits outside ; eaves broad, solid.
Girdle narrow, thin, covered with excessively minute, closely imbricating, striated scales.
Length 22, breadth 9 mill.
Monterey, California.
Callixtochiton fimbriatus CPR., MSS. 1875. Not Callochiton fim- briatus Cpr. in COOPER, Geographical Catalogue of the Mollusca found west of the Rocky Mountains, between Latitudes 33° and 49° North (Geol. Surv. of Cal.), p. 23, 1867 (no description),^ Callisto- chiton pulchellus, Cpr. MSS. 1875.
? Chiton ( Callochiton} fimbriatus Cpr., ORCUTT, Proc. U. S. Nat. Mus. 1885, p. 544 (1885), no description. Not Chiton fimbriatus SOWB.
This species is readily separated from the next by the smaller number of ribs on the head and tail valves, the less distinctly bicos- tate lateral areas, and the far less elevated tail valve, which has, besides, a posterior terminal mucro.
The specimens before me were collected by Henry Hemphill at Monterey. A species under this name has been reported from San Diego and from Catalina Island, but the identity of the specimens with the present species is open to doubt, although its occurrence in those places is not improbable.
The name of this species is involved in some obscurity, owing to the fact that no diagnosis or description whatever has heretofore been published, although the name fimhrintns has appeared in several lists. This much however is certain: that the original fimhrintn* Cpr. of Cooper's Catalogue, the unique type of which is said to be in the Smithsonian Institution collection, is not the fimbrixfus of Car- penter's later MSS. ( Vi>1>- < 'arpenter's MSS. vol. I, p. 135) ; and we
266 CALLISTOCHITON.
have no means of knowing whether the C. fimbriatus of Orcutt's San- Diego list was identified from Carpenter's earlier type specimen, or his later MSS. Everything considered, the best course open to us seems to be the selection of an entirely new name. The type is in the collection of the Academy.
C. INFORTUNATUS Pilsbry, n. sp. PI. 59, figs. 37-42.
Shell large, regularly ovate, the dorsal ridge obtuse ; valves arcuate ; mucro obtuse, median. Olivaceous, sometimes spotted with paler on the ribs and jugum.
Central areas having about 12 parallel lirse on each side, decussated, the interstices having square depressions. Lateral areas having two very strong rounded tuberculose ribs. Anterior valve with 9, pos- terior with 7-8 elegantly spreading ribs.
Interior: posterior valve having 7-8, central 1, anterior 9 slits ; teeth concave outwardly, obtuse, slit at the apices of the ribs, some- times with an intercalated slit or abnormally serrate ; teeth of poste- rior valve very obtuse, hardly sloping ; eaves small, delicate. Sinus wide, flat, but little angular, sometimes crenulated by the riblets of the exterior. Girdle irregularly imbricated with flattened scales, each one about 6-striated (fig. 39.)
Length 17*, breadth 8| mill.
Equador (Cuming) ; La Paz, W. Mexico (Pease.)
Callistochiton pulchellus CARPENTER, MSS. Not C. pulchellus Gray, q. v.
The sculpture of the central and lateral areas resembles that of C. palmulatus, but the tail-valve (figs. 38, 42) is entirely different in form. This shell was sent to Dr. Carpenter by Cuming as the true C. pulchellus of Gray, but it is certainly not that species. The above description and the figures are from Carpenter's MSS. and unpub- lished drawings of his type.
The shell recorded by Dr. J. G. Cooper from " Catalina (or other?) I., Cal." under the name Callocliitmt ihnbrintus Cpr. MSS., and by Carpenter (in MSS.) from " S. Pedro " (both referring to the same specimen) may be a variety of this species, but no definition of it has been published, the locality is uncertain, and Dr. Carpenter in his later MSS. shifted the n&m6 fimbriatut to another species, leaving the form under discussion as a nameless variety of his C. pulchellus. Under these circumstances it has been thought best to expunge the name fimbriatiui from the list of valid species.
OALUVfOCHITOV, -'•"
C. JAC«»i; r.l s (Jould. f'ntiiflli'cd.
Shell small, ashy, elongated, elliptical, hardly carinate.l ; end valves very lar^-, vaulted, ornamented with 10 scaly nuliatinir ril>> ; central areas cancellated; lateral areas conspicuous, bicostate. Ligament narrow, covered with minute elongated scales.
Length 12, breadth 5 mill. (UM. )
Interior: posterior valve having 7, anterior 10, central 1 slit; teeth acute, curved outwardly ; eaves solid ; sinus wide, nearly flat, laminate, the lamina more or less separated from the sutural plates [by notches at the sides of the sinus]. Girdle imbricated with flat,
striated scales. ( Q>r.)
Simoda, Japan (North Pacific Expl. Exped.)
C. (Leptochiton) Jacobceus GLD., Proc. Boston Soc. Nat. Hist, vii, p. 164 (Dec., 1859) ; Otia Conch., p. 117. — Caltistochiton jacobceus CPR., MSS.
Carpenter gives the following notes ; but it must be remembered that his C. pulchellus is not the true pulchellus of Gray.
" If this shell had come from Central America, I should certainly have regarded it as C. pulchellus with which it exactly agrees in sculpture, number of ribs, size andstriation of the scales, and general aspect. Indeed it can scarcely be separated as a variety, like the Californian shell. Inside, however the teeth are somewhat sharper, one of them having an extra slit. The lamina which lines the sinus is very thin and sharp, generally (but not always) marked off' from the sutural plates by slight slits. In some valves, the lines which mark it off are perceptible, but they do not serrate the edges. It is also much broader in some valves than others. Whether the species are or are not identical, cannot be decided from the single specimen in the Smithsonian Museum. It is very singular that a shell from equatorial S. America should be replaced by a very distinct species in the Bay of Panama, should reappear in the Gulf of California, be still found in the temperate seas of California and lastly display a representation on the shores of Japan." (CJpr.)
C. ELENENSIS Sowerby. PL 59, figs. 27, 28.
Shell oblong, pallid ; back rounded; anterior valve radiately sul- cate ; lateral areas of the intermediate valves swollen, unisulcate; posterior valve retuse, radially sulcate behind ; central areas of the intermediate valves irregularly sulcate-scabrous ; margin smooth.
Length '6, breadth -3 inch. (Sowb.*)
St. Elena and Panama.
268 CALLISTOCHITON.
Chiton elenensis SOWERBY, P. Z. S. 1832, p. 27.— C. ellinensis SOWB., Conchol. Illustr., p. 6, f. 69. — Ischnochiton elenensis CPR., P. Z. S. 1865, p. 275. — Probably Chiton janeirensis var.f GRAY,Spicil. Zool., not of Sowerby and Reeve.
Sowerby's original description and figures given above. I have not seen this species, and place it in Callistochiton with some doubt, as its internal characters may demand for it a position in Ischno- chiton. Haddon considers it very closely allied to C. deeoratus Cpr. Carpenter has identified with this species a Panama form collected by Prof. C. B. Adams. He gives the following description of it :
"Outside having the central areas decussated with about 20 parallel bars ; lateral areas having two strong, swollen, tuberculose ribs. Interior having the sutural [posterior] margin reflexed, tuberculate, with a small sinus ; insertion plates 1-slit, sinus 'very broad. Front valve having 12 ribs, not very strong, and ten slits within, the teeth acute, eaves narrow. Posterior valve having the mucro subposterior, depressed ; the slope behind it expanded, con- cave, with about 12 subobsolete ribs; inside with 9 slits, the teeth short, eaves small, callous within. The central valves of this species are normal ; but the posterior valve offers a transition toward Callo- chiton L=Callistochiton], the outside being concave posteriorly, the insertion-teeth short, and the eaves callous. (Cpr. in P. Z. S.). The sinus is unusually broad and shallow, the sutural laminse not being marked off. (Cpr.)
C. EXPRESSUS Carpenter. Unfigured.
Shell similar to /. elenensis, but flesh-colored. Central areas hav- ing 10 distant closely decussated bars ; dorsal ridge acute, lateral areas having two very strong, narrow ribs with narrow tubercles ; inside having the posterior margin flat, hardly tuberculose, hardly si mi a ted ; sinus narrow, angulated at the jugum. Anterior valve having 10 strong, narrow ribs; interior as in elenensis, but with 8 slits. Posterior valve having a flat posterior mucro, the slope behind expanded, hardly concave, with about 7 very strong ribs; inside having about 7 slits, the eaves flat.
" With a strong general resemblance to /. e/> //' //x/x, the differences in detail in the only two specimens examined, as above stated, appear of specific importance. If only varietal, it is equally impor- tant to notice how much change is tolerated by the habits of the animal. It may be the shell called Cliilan <-?at /trains by Professor
269
Adams, of whieh there were no duplicates to compare. Jt offers a still more marked transition to (<///,><•/, Iton, the mar-jin of the pos- terior valve l.eiiiLr somewhat pectinated by the great projection of the ribs. (Q>r.)
rnnama (C. B. Ad.)
Ischnochiton (? yar.) expressus CPR., P. Z. S. 1865, j>. 'J7">.
This species, like the last, is not known to me by specimens, the above description and notes being from Carpenter's paper in the P. Z. S. In his MSS. Carpenter places it in the smooth scaled section of Inch noch Unit, and gives some additional notes, as follows: "This shell is almost exactly like the young of /. serratus, agreeing not only in the peculiar and beautiful sculpture, but even in the mantle scales. Yet it differs remarkably in the abnormal, narrow pointed sinus, in which respect it resembles J. tectiformis. One of these species is probably the C. clathratus of C. B. Ad. (Pan. shells, p. 242), and possibly of Reeve."
C. DECORATUS Carpenter, n. sp. PI. 58, figs. 17-20.
Shell oblong, moderately convex, obtusely subangular along the dorsal ridge, the side-slopes slightly convex. Surface rather shining, varying in color from olive-buff to dark green, uniform or having darker flammules and spots.
Apices of the median valves eroded. Lateral areas raised, each rendered bicostate by a central sylcus, and having a few uneven longitudinal impressed grooves, giving it a terraced aspect. Central areas having numerous parallel longitudinal ribs, the intervals closely latticed across, this sculpture obsolete on the ridge, where there is a broad V-shaped smooth area, which rarely shows a few diverging subobsolete ribs. Anterior valve having 11 rounded ribs. Posterior valve less elevated than the anterior, highest at the front margin, the mucro depressed, post-median ; posterior area having 9-10 rounded ribs.
Interior bluish, generally marked with olive or green at jugum, bases of the sutural-plates, and slit- rays. Sutural plates wide, separated by a square sinus notched at each side. Anterior valve having 9 or 11, central 1, posterior valve 9-12 slits ; teeth rather sharp, smooth ; slit-rays distinct and porous. Eaves narrow.
Girdle narrow, ashy-brown, covered with minute, striated, closely imbricating scales.
Length 20, breadth 9-10 mill. ; divergence about 110°. Todos Santos Bay and near San Tomas River, Lower Calif orn in.
270 rAI.USTui HITON.
CaUistochiton cfoeorofti* CPR., .I/NX. — Chiton (CaUistochiton) decor- ati(s Cpr., ORCUTT, Proc. U. S. Nat. Mus. viii, p. 544 (1885,) no description.
It has been reported from San Diego by Orcutt and from La Paz by Carpenter (Pease coll.)
The partially sculptured central areas are peculiar and character- i-tic-, and the tail valve presents features not found in the other species of the same region. The figures 17-20 may be regarded as the types, but some individuals show some very obsolete coarse ribs in the front part of thejugal smooth tract.
The type is in the collection of the Academy.
C. GABBI Pilsbry, n. sp. PL 60, figs. 7-10.
Shell oblong, convex, rather sharply carinated, the side-slopes somewhat convex. Surface lusterless, the central areas light brown, lateral areas olivaceous-brown.
Median valves not beaked ; lateral areas composed of two strongly elevated ribs, bearing acute grains, the posterior rib wider, having an additional row of smaller grains along the sutural margin ; the suleus between the ribs rather wide, minutely pitted. Central areas having about 15 parallel longitudinal riblets, becoming diverging toward the outer margins, the interstices very closely, sharply cross- latticed ; region of the beaks smoother, pitted and microscopically granulate. Anterior valve having 9 strongly elevated ribs separated by pitted intervals of the same width as the ribs, the latter bearing acute grains; the posterior rib on each side wider, with sutural grains ; region of the beak excavated. Posterior valve elevated at the front edge, rapidly sloping backward, the mucro about c> iitral, much depressed; posterior area sculptured with 7 rather broad wave-like radiating ribs surmounted by acute grains.
Interior light olivaceous, with dark markings under the beaks. Sutural plates well developed, separated by a narrow, angular, con- vex sinus. Anterior valve having 9, central 1, posterior valve 8 slits ; teeth rather short, smooth, festooned and slit at the ribs. L expect <tl I ij in the tail valve, extremely narrow.
Girdle covered with very compactly imbricated, wide, finely striated scales, which are arranged in alternate patches of olive-bluish and lighter, the light patches being composed of mingled bluish, tawny and white scales (fig. 7.)
Lemrth 14, breadth 8$ mill. ; divergence about 110°.
Gulf of California (Gabb.)
« \l MM", IHTON. L'7
In the depressed inucro ami internal colorim:, a- well a- tin- nar- row eaves, this sp< ;d»les ('. <l>r,,r<il n.< ( '|»r. ; but t he -ciilpt u r<- is iiuicli stronger, and i.~ nut obsolete at the dor>al ridire of each valve. The (\ of S..\vrrl»y, a species which I have not seen, seems to be similar, bat judging from Sowerl>y'> figure the nuiero of that species projects at the summit of the posterior slope, which is far from bring the case with the form before me. The form described as elenensis by Carpenter differs in having a very wide sinus, weaker sculpture, etc. It should be compared with Carpenter's untiguivd Inchnochiton expressns, a species not known to me autopt- ically.
The type is in the collection of the Academy.
C, ITU IIKLLUS Gray. PI. 60, figs. 1-6.
Shell oblong, rather depressed, the dorsal ridge subangular, side- slopes convex. Of a soiled buff color, the girdle darker, ashen.
Valves not beaked ; lateral areas raised, cut by a sulcus into two prominent ribs, of which the posterior is wider, sculptured with low, transversely elongated grains, serrating the sutures, the anterior rib having less conspicuous grains. Central areas in the middle pitted in diagonal series, the pattern becoming coarser on each side, then changing into longitudinal fine riblets on the outer half of each side. Anterior valve having 10 (or 12) strong rounded ribs, cut into low transverse grains by superficial concentric impressed lines. Posterior valve abruptly depressed at the mucro, which is behind the middle, the forward area level, reticulated, the posterior area bearing 7 stout ribs ; the posterior ones are strongly bent.
Interior whitish ; sutural-plates rounded, separated by a wide sinus, which is angular but hardly notched at the sides, and not per- ceptibly laminate. Slits in head-valve 10, median valves 1, poste- rior valve about 14 ; teeth thin but normal in front and median, irregular in the posterior valve. Eaves narrow.
Girdle narrow, densely imbricated ivith minute smooth, flattened scales.
Length 10, breadth 5 mill.; divergence 135°.
Arica, Chili (Hennah.)
Chiton pulchellus GRAY, Spicilegia Zoologica, pt. 1, p. 6, t. 3, f. 9, (July 1, 1828).— REEVE, Conch. Icon., t. 23, f. 153 (? and perhaps t. 25, f. 168).— Chiton (Callochiton) pulclicllus MORCH, Mai. Blat. vii, p. 176. — C. bicoxtatus D'ORBIGNY, Voy. dans 1'Amer., Merid., p. 486, t. 81, figs. 7-9.
L' , _' CALLISTOCHITON.
? Chiton pulchellus C. B. AD., Cat. Panama Sh., p. 243 (in part). — " Chiton pulchellus " CPR., P. Z. S. 1865, p. llS.— Callistochitnn pukhri&r CPR., J/N£
Not Callistochiton pulchellus of Carpenter's M8S. — Not Chiton. l>\ilchellus of d'Orbigny, Voy. dans l'Ame*r. Me*rid., p. 489.
The netted sculpture of the dorsal areas is unlike other species from the western coasts of the Americas. Figures 3-6, drawn by the author, should enable any one to identify the species readily. The small size is also rather characteristic, as well as the profile of the posterior valve (fig. 5.)
I have but little doubt of the identity of Carpenter's C. pulchrior (=0. pulchellus Cpr., P. Z. S. 1865, p. 276) with the true C. rl,,!In8 of Gray. Carpenter separated pulchrior from after studying specimens supposed to be of the latter species sent him by Cuming ; but it is clear to me that Cuming's identification was erroneous, and therefore the position taken by Carpenter becomes untenable.
Drawings of the form called pulchrior, prepared for Carpenter, are reproduced on my plate 59, figs. 21-26. The sculpture is not well rendered, and if the drawing is accurate, the tail-plate differs somewhat in profile.
Gray's description of pulchellus is not as good as Reeve's and his figure (pi. 60, fig. 1) is poor. The detail figure given by Reeve is copied on pi. 60, fig. 2. Gray's description is as follows :
Shell oblong, ^elongate, slightly keeled, yellowish-white. End valves distantly, unequally, radiately ribbed; lateral areas of the middle valves with two broad, regular ribs ; central area closely and deeply punctured. Margin yellowish- white, with very minute bran-like scales. The ribs of the lateral areas are rarely bifid.
Length 3, breadth i of an inch. [=about 9x4 mill.]
Inhab. Arica, Peru, Rev. W. Hennah, Brit. Mus. (Gray.)
The species described from Arica by d'Orbigny is in all pro It- ability the same as Gray's form, but the figures are very poor. The original description is here translated :
C. bicostatu* d'Orbigny. (PI. 59, figs. 43, 44). Shell oblong, swollen and obtuse, entirely whitish. Anterior and posterior valves sculptured with broad, radiating ribs and some concentric lines of growth. Lateral areas of the intermediate valves each ornamented
( \i i WTO in •with tWO very larirr, prominent ribs ; median ide and
punctate. Girdle minutely scaly. Len^-tli 7 mill. (0
Arirn, under stones at l«»w \v;r
\lliedt" r. inilrlicf/im of < iray, ditli-rmi: in tin- irranulous and scaly, not smooth, Lrmlle, 1>\ the two ribs ..i'the lateral areas instead of three, and hy the punctate central areas, which in the other species are striated." (Orb.)
It must l>e remembered that the " C. pulchellus of Gray" alluded to hy Orhiirny, is not tin- true jutlchellus of Gray, but some totally ditieivnt species of Chcetopleura or of Tonic!".
( '. -in ri i. I:\VOKTHIANUS Pilsbry, n. sp. PL 21, figs. 42, 43, 44, 4-">, 4U.
Shell oval, depressed but dorsally carinated, the side-slopes nearly straight; lateral areas strongly raised, bicostate, the ribs nodose; central areas having a coarse raised net-work in the middle, and longitudinally ribbed toward the sides. Girdle broad. Color of both xliell ami yirdle intense orange yellow.
The lateral areas bear two strong ribs which bear stout transverse tubercles, the intervening spaces being closely granulate. The central areas have coarse wi-likc sculpture (fig. 45), which becomes much finer toward the beaks, and is transformed into a longitudinal cos- tulation at the sides. The front valve has 16 or 17 strong, tuberculate radiating ribs, the whole covered by a fine granulation. The poste- •"/?•' />• Depressed, having a rather low but acute and slightly pos- terior mucro, the slope back of it being concave. It is sculptured similar to the head-valve, except that the concentric sculpture pre- dominates over the radiating.
The interior is flesh-colored; anterior valve with 10, central 1 slit; sutural plates low and rounded ; sinus shallow, flat.
Girdle wide, compact, very densely clothed with closely imbricat- ing scales, the terminations of which are not striated, although the basal portions are distinctly grooved (pi. 21, fig. 46.)
Length 14, breadth 9 mill.
Key West, Fl»ri<l,, , Henry Hemphill.)
This handsome species constitutes one of the links between Callis- tochiton and Ischnochiton, agreeing in the teeth with the latter genus. The sculpture, however, is much more like Callistochiton pnlcht II us than like any Ischnochiton known to me ; but, on the other hand, the profile of the tail-valve differs utterly from that West Coast species.
18
L'7 i CALLI8TOCHITON.
It seems to resemble the unfigured /. lab'rithi* Shuttlew. in color
and somewhat in sculpture; but Shuttleworth says of his species "raids
terminalibue eubconcenbrice lineatus punctatisque ; medii* non c<irin-
etc., and this in no way agrees with the species described
above.
The type is in the collection of the Academy.
C. ANTIQUUS Reeve. PL 59, figs. 29, 30, 31, 32, 34, 35.
Shell oblong-elliptical, moderately convex, obtusely carinated, the side-slopes convex ; of a uniform soiled buff, or stained with reddish along the back ; sometimes tinged with olive-green.
Valves not beaked. Lateral areas composed of two strongly elevated ribs, bearing compressed grains, the posterior rib wider, its grains denticulating the suture. Central areas having a honey-comb reticulation near the beaks, on the sides changing into fine longitu- dinal riblets with minutely latticed intervals. Anterior valve hav- ing 11-12 very strong, rather narrow and acutely granose ribs. Posterior valve depressed, sloping backward from the front margin, the mucro depressed, slightly in front of the center; the posterior area having 8-9 strong granose ribs.
Interior bluish-white, sutural plates low, rounded, separated by a broad shallow sinus. Anterior valve having 9, central 1, posterior 9 slits, corresponding to the external ribs ; teeth smooth, rather sharp, curved and concave outside as usual in Callistochiton. Eaves rather narrow.
Girdle wide, thin, leathery, compactly covered with very small convex and apparently smooth brown scales, having light colored larger scales mingled among them (fig. 34.)
Length 17, breadth 10 mill.; divergence 110°-120°.
Port Molle, Queensland (Coppiuger), Port Jackson, X. S. Wales (Angas, Brazier, Challenger.)
Chiton antiquus REEVE. Conch. Icon., t. 25, f. 169 (poor). — Lepidopleu/nu antiquus ANGAS, P. Z. S. 1867, p. 223. — Callistochiton «////'/ /'//.-• ('ri:. MS. and HADDON, Challenger Polyplac., p. 20. — Chiton (Git/ixtochif'ni') anfiquus E. A. SMITH, Zool. Coll. 'Alert' p. 79. — Callistochiton sarcophagus CPR., J/>
This species has the same style of honey-comb or netted sculpture toward the beaks that C. pnlchellus and C. shuttleworihianus show. A specimen in which the number of ribs on the head valve is increased by splitting to 17, and on the tail valve to 16 is on record;
< LLLWTCX m
bat the number in front Ifl ordinarily from into 1'J, In-hind from -8 to ]-. The tail valve is much depre— ed, as in (\ tjnl>hi.
Carpenter deseril>ed a Iarir<-, line speeimen as ( . Mreophagut, hut upon examining Ueeve's type he concluded that it was merely a well developed f//i//////i/x. Tlie type is in the Uritish Museum.
C. coiM-iN<;i;i:i Smith. PI. o<>, fig. 36.
Shell elongate, greenish-white, stained with a dark green color alonir each side near the girdle, with a paler indistinct stripe on each side of the central line, the apex of the valves heing somewhat livid. Central valves with a straight posterior margin, arched, with only the faintest indication of a carina at the vertex. Lateral areas somewhat raised, with two radiating rows of coarse transverse rugse, of which the hinder or marginal are the largest. The surface between them is finely granular. Central areas covered with a more or less criss-cross granulation, the granules at the center being very minute, and gradually increasing in size toward the sides, where there is very little of the criss-cross arrangement seen at the vertex, but rather a longitudinal disposition of them. The front valve is minutely granulated and has about twenty fine radiating ridges, here and there some of them bifurcating near the circum- ference. Posterior valve rather large, concave behind the sub- central mucro, in front of which the surface is sculptured in the same manner as the front of the central valves, as is usual with most, if not all Chitons. The posterior half is finely grained and sparsely covered with pustules of different shapes and sizes. The coarsest being near the margin and the smallest near the center. The iusertioual plates are thin, with twelve slits in the last, at unequal distances, eleven in the front one, and one on each side of the intermediate valves. The interior is pale bluish, the latter valves having an olive- brown stain radiating from the vertex behind on each side, and the two terminal valves have marks of the same color near the middle.
The girdle is covered with alternately pinkish and dark grayish patches of fine oval compressed imbricating scales, of which those toward the outer margin are much smaller than those near the valves.
Length without girdle 21 millim. ; diameter of fifth central plate 8 mill. (Smith.')
Port Jackson, Australia (Coppinger.)
Chiton (Callistochitoii) coppinyeri E. A. SMITH, Rep. Zool. Coll. H. M. S. 'Alert,' p. 80, t. 6, f. E (1884.)
276 CALLISTOCHITON.
The only published figure of this species is very poor. Smith writes : closely allied to C. antiguus, but it is differently and more finely sculptured, and the scales on the mantle are larger.
The type is in the British Museum.
C. ADENENSIS Smith. PI. 59, fig. 45.
Shell small, depressed, hardly carinated, unicolored pale brown- ish. Anterior valve having about 22 granulate radiating ribs. Lateral areas composed of two strong granulate ribs ; central areas longitudinally granose-lirate, the lirse more delicate in the middle than at the sides. Posterior valve having about 25 delicate granulate lirce. Girdle pale brownish, very minutely scaly.
Length 14, breadth 9£ mill. (Smith.')
Aden.
Chiton (Callistochitoii) adenensis E. A. SMITH, Proc. Zool. Soc. Lond. 1891, p. 421, t. 33, f. 7.
The sculpture of this species is of the same character as that of C. antiguus Reeve, but not quite so pronounced, and the rays of both the terminal valves are more numerous. (Smith.)
The type is in the British Museum. The italics of the above description are my own.
C. HETERODON Pilsbry, n. sp. PI. 60, figs. 11-15.
Shell oblong, rather elevated, carinated, the side-slopes nearly straight; buff- white, sparsely dotted on the ridge with olive-black and having one or two spots of the same on the sides of each valve ; the girdle yellowish, having narrow slate-colored bars.
Valves having rather acute but not backward-projecting beaks. Lateral areas raised, having 3 or 4 ribs, being primarily divided by a deep sulcus into two ribs, the posterior of which is again divided ; and sometimes the front rib also is split into two, especially on the second valve ; the interstices are coarsely pitted, and the posterior rib is ribbed across, dentating the sutures. The central areas have about 11 rather narrow but strong longitudinal riblets on each side of a wider dorsal rib ; the interstices nearly smooth. Head valve having 11 (or 13, by splitting) strong denticulate ribs. Tail valve narrower than the head-valve, not depressed, the mucro obtuse, post median ; posterior slope convex, having 11 radiating ribs.
Interior pure white. Sutural plates narrow, separated by a square, slightly deticulate sinus, which is distinctly laminate and slightly notched at the corners. Anterior valve having 8, central valves 1,
NUTTAI.MNA. 277
posterior valve 13 slits ; teHh blunt, finely and deeply pectinated out- side and at the edge. Eaves solid.
< Girdle broad, compactly covered with shining, deeply sulcated scales, measuring about one-third of ;i mi Him. in breadth, and the terminal margin of each is smooth (fig. 13.)
Length about 16, breadth 10 mill. ; divergence about 105°.
Red Sea.
This species has far fewer ribs on the terminal valves than C. adenensis Smith, although the lateral areas have more ribs. The girdle scales are coarser than in other species, and they have the peculiarity noted in C. shuttleworthianus, of being smooth at the distal end. I have seen no Chitons of other genera having this feature. The second valve has several slightly diverging riblets at the front of the dorsal area. The teeth are as deeply pectinated as in any species of typical Chiton or Acanthopleura ; and it is by no means impossible that the species belongs to the former genus. I have preferred to retain it in Callistochiton on account of the peculiar sculpture, and the relation in which the slits stand to the ribs.
The type is in the collection of the Academy.
Var. SAVIGNYI Pilsbry. PL 60, fig. 16.
This form is known to me by Savigny's figures, which indicate a species closely resembling the last. The head valve has 11, the lateral areas two ribs ; the tail valve is smaller, having 9 ribs ; central areas with about 9 ribs on each side, and a rather wide smooth tract in the middle. Scales of the girdle sulcate, with .smooth outer edges.
SAVIGNY, Descript. de FAegypte, Gasterop., t. 3, f. 8-1, 8-2, 8'3.
Genus XXIV. NUTTALLINA Carpenter, 1879.
=Nuttallina plus Middendorfia plus Beanella Cpr.
Valves exposed, granulated, the lateral areas having 2, head yalve numerous low radiating ribs ; insertion-plates sharp, the slits corresponding in position to external ribs* Mucro behind the middle, the posterior teeth directed forward. Eaves and sinus very spongy. Girdle varying from spiny to scaly.
This well-defined genus probably has the same apparently anomalous distribution as the coral-red Leptothyras ; species being found in the Mediterranean, the Japanese Seas, and the coast of Cali-
278 Nl-TTAI.l.INA.
i'oniia. Xuttallina is divisible into two closely allied sections or sub- genera, as follow- :
Siihuvniis Xn I'M. i. IN A .*. str. Side-slits two in each valve, the pos- terior one generally subobsolete, but indicated by a porous slit- ray. Teeth hardly or not thickened at the edges of the >lits ; girdle wnh minute, often chaffy spinelets and longer round spines.
Sul .genus MIDDENDORFFIA Cpr. Side-slits single. Teeth more or -- thickened at the edges; girdle clothed with minute striated flattened scales and having a marginal row of flat striated bristles.
Subgenus NUTVALLIXA Carpenter (restricted.)
Xiitt'illina CPR., Table of Reg. Chitons, 1873.— DALL, (Amer. Journ. Conch, vii, p. 134), Proc. U. S. Nat. Mus. 1878, p. 333 (Feb. 14, 1879.)
Valves exposed, granulated, having long smooth sharp teeth ; the slits of the median valves obsoletely doubled, 'those of the anterior valve corresponding in position to the external ribs, the teeth not thickened at the edges of the slits; mucro of posterior valve poste- rior, terminal but not marginal; teeth of posterior valve short, chisel-shaped, directed forward. Eaves and sinus spongy. Girdle bearing short, rigid spines. Gills extending the whole length of the foot. Type X. scabra Cpr.= CA. californiciis (Nutt.) Rve.
The shell in this genus resembles that of typical Acanthophnrn (A. spinosa Brug.) in the elongated valves, double slitting of the median valves, and the spinose girdle. It differs in the smoothness of the sharp teeth and the spongy sinus, — characters of much greater importance than those first enumerated. The likeness of Nuttallina to Acanthopleura is, in fact, merely one of analogy, having no mean- ing deeper than that story of the development of different stocks along parallel lines, repeated so often in the history of Chitons. In its fundamental characters, Nuttallina agrees with Ceratozona ; but the more shelly texture of the girdle-spines, the spongy sinus, and propless teeth afford sufficient ground for generic distinction.
Authors and collectors have gnu-rally recognized but one Cali- fornia species ; but there seem to be two. It is useless to try to .-tudy thnn without separating the valve?, as the specific characters are not very apparent in specimens preserved in the ordinary manner.
279
Tin- white -piiM-- are oftm ^trialed when JOUllg, as are the scale-
•///•/.
N.CAI ii <H;\ICA Nuttall. PI. -VI, lii-. '-'::, 24; |.l. 56, fiir. IL'
1 l, 15, 16; 17,18.
Shell elongated, more than twice as long as wide, moderately elevated, carinated or somewhat rounded. Surface finely «-Mrru^ated- irranular, lusterless ; color dark brown, dark olive-brown or Idack- ish, unicolored or having one or three whitish stripes along the summit of the second valve.
Median valves strongly beaked, v-shaped, the anterior margin of the tegmentum trilobed; having a smooth shining rounded dorsal ridge (sometimes obsolete and often eroded), bounded by a pair of <lii'''i-giiif/, shallow furrows ; the entire sides of the valve* < />/' "/•'/ <nid lateral areas) closely granulated, the granules irregularly arranged in rows. Lateral areas not raised but indicated by a low curved diagonal rib, behind which and parallel to it, there is a shallow sulcus. Anterior valve having 11 low rounded radiating ribs, the entire surface granulated. Posterior valve depressed, small, the mucro posterior and terminal, projecting beyond the posterior margin of the eaves.
Interior bluish, sometimes stained with blackish at jugum and bases of the sutural plates. Sutural plates very long, separated by a wide, deep, square sinus; behind which is a punctate and I'm area. Anterior valve having 11 or 10, median valves with two slits, or at least two punctulate slit-rays, the posterior slit being usually indistinct or wanting from the more or less complete obsolescence of the posterior tooth ; teeth sharp, smooth, long, not thickened at the edges of the slits. Posterior valve having 8-9 slits, the teeth chisel- shaped, sharp, smooth, very strongly directed forward. Eaves nar- row, spongy.
Girdle closely covered with short, rigid calcareo-corneous spine- lets, mostly of a scorched brown color with a few white spines inter- mingled (pi. 54, fig. 24.)
Length 37, breadth 15 mill. (Large specimen from Monterey.)
Length 26, breadth 13 £ mill. (Specimen collected by Nuttall.)
Vancouver Island south to Piedras Blancas, near S. Simeon, San Luis Obispo Co., California.
Chiton californicus NUTTALL in Brit. Mus. and Mus. Phila. Acad. — REEVE, Conch. Icon., pi. xvi, fig. 89 (March, 1847).—
280 NUTTAI.I.INA.
.«>nl>rn On., MS. and of BALL, Amer. Journ. Conch, vii, p. 184; Proc. U. S. Nat. Mus. 1878, p. 333.— AcauthofL-ura scabra OK., Ilrit. Asso. 1863, p. 649.— STEARNS, Proc. Calif. Acad. iii, p. 346.— Nutt'ill',,,,,., Mdbra Kr.r.r. West Coast Shells, p. 108, f. 96 (1887.) Not Chiton scnber Reeve.
This is the form which has generally been called "JV. scabra." Reeve's figure is not good, being drawn from a short specimen abnormally shortened by contraction. It should be noted that the shortest specimen in the large suite before me is also one of those collected by Nut tall, who presented a complete set of iiis Califor- nian shells to the Academy.
In this species the individual valves are longer than in the follow- ing form, but on account of their deep imbrication the difference is not in most cases noticeable until the shell is dissected. The girdle is much more densely clothed with spinelets.
The areas of distribution seem to be separated, the true californica extending southward past Monterey Bay, — the southern out-post of so many species of the Columbian district, — to near S. Simeon, S. Luis Obispo Co. The other species, scabra, has not been noticed north of Sta. Barbara Island, and San Diego on the mainland. There is still a considerable stretch of coast from which we have no record, or at least no record in which the two forms are discrimin- ated. This coast should be searched for intermediate forms.
Dall gives the following notes on the station of this form : This r-iniriilar species (not yet obtained from Alaska, but which will prob- ably be found there), like some Lilorinas, seems habitually to prefer positions where it can at most be reached by the spray in stornis, on -ed headlands, where the breeze comes in damp and cool from the sea. The pointed valves overlap each other so much that when the creature is curled up they project from the girdle, giving a pect- inated outline, unusual in Chitons. The valves are almost always eroded, even the prominent mucro is often hollowed out, and the sculpture can rarely be seen except in young specimens. The color i.- irrayMi «>r l>n>wni.-h. with whitish streaks; the girdle has the aspect of dead brownish-black moss, sometimes with ashy spots at the sutures.
N. SCABRA Reeve. I 'I. :> J, figs. 21, 22 ; plate 56, figs. 19, 20.
Shell similar to N. californiea, but having the individual valves
much shorter in proportion to their width : the outer layer of
the median valves produced at the sides anteriorly, curving broadly
M i i \ i i 281
forward and literally Upon thfl sutural plat<--; flu- medi;m i and sulci inoiv or • !••. 'I ail valve -li'Ti.r, with less pos-
terior macro, Oolor of yalvei li.irht vaiir-at.'d.
Girdle rusty brown or alternately blacki-h and white ; rather spar-ely scattered white sj)ik«--lik<- -j.i • one or two at each suture. PI. ">J, fig. 21). length :>!», breadth L3 mill.
Santa Barbara Is. ami XHH I>i»/()to between Soo/mn
<Ul<I rtd. tie -1 /'/V»»/'f*S, Jjnir,,- ( 'il/ifi>rn i'l .
Chiton scaber h'u.vi:. Conch. Icon., t. 17, f. 106 (March, 1847).— Acanthopleura fluxa CPR., Suppl. Rep. Brit. Asso. 1863, p. 649; Proc. Cal. Acad. iii, {>. 211, (1865.)
This species has hitherto been confused with the preceding by most collectors. Carpenter, however, distinguished it, and gave the name fliu-n. Although the individual valves are much shorter in this species than in N. californica, they overlap much less, so that the total length of the animal is about the same in the two species. The elevation is about equal also, but in californica the girdle is generally wider at the sides, especially in old specimens. In size, individuals of the northern species considerably exceed any of the southern I have seen, although the majority of specimens do not
differ much.
•
N. ALTERNATA Sowerbj. PL 54, figs. 25, 26, 27.
Shell elongated, subdepressed, very minutely granulated ; lightly keeled by a central rib ; lateral areas separated by a lateral rib. Anterior valve radiately ribbed ; posterior valve small.
Girdle furnished with minute spines, alternately banded black and white. Length 15, breadth 8£ mill.
Narrow, rather flat, minutely granulated; the first valve radiated •with slightly raised ribs, the intermediate have each three faint ribs, one dorsal, the other two lateral ; the la>t U very small, with a nearly terminal apex. The margin is covered with very minute spines, in alternate patches of black and white; general color, dark olive-green. (Sowb.)
(Mus. ( 'inning).
Chiton alternatus Sown., Mair. of Nat. Hist., IMn, p. 288 ; Conch. Illustr., f. 141.
282 \ I.I.I N A.
This form has not been noticed by subsequent authors. It seems- to agree with the preceding species in the dorsal and lateral ribs, and also those upon the anterior valve ; but as the interior is unknown, its reference to Xntt<t/lina is provisional.
Subgenus MIDDENDORFFIA Carpenter, 1882.
ir < , /,,/ym CPR., MS. and in DALL, Proc. U. S. Nat. Mu>., 1881, pp. 284, 287, type Chiton polii Phil, non Desh., (Jan. 20, 1882.) — Dawsonia CPR. 1873, preoc., same type. — Beania CPR. 3/5., not of Johnstone. — Beanella DALL, Proc. U. S. Nat. Mus. 1881, pp. 284, 287, type C.pseudorissoi CPR. ined., in Mus. Cuming no. 51.
Valves exposed, rather square and short, granose outside with low ribs at lateral areas and on head- valve. Insertion plates rather sharp, not notably rugose, the teeth more or less thickened outside at the slit-edges; slits of head-valve corresponding in position to exter- nal ribs. Tail valve small with mucro behind the center, the teeth directed forward, eaves and sinus coarsely spongy. Girdle narrow, compactly covered with a pavement of minute striated scales and spinose at the edge. Gills extending forward over three-fourths the length of the foot. Type Ch. cinerem Poli, not Linn.
This subgenus agrees with Nnttallina in the markedly porous or spongy texture of eaves and sinus, in the external sculpture, and in the forms of the insertion-teeth, except that in Middendvrffia these are thickened at the slit-edges. It differs from Nuttallina in the rather flattened scale-like, rather than spine-like girdle appendages but the younger spines of Nutallina scabra, when examined under a strong power are often seen to be striated, appearing like finely fluted ivory pillars ; and in some specimens of the same species there is a marked tendency to form a marginal fringe of longer spines. The differences between the West American and Med- iterranean forms are therefore not great, being confined to (a) the irinlle covering, which often varies as much in closely allied species, such as ItehnockUon r,tn*i>'n-im* and /.m-rior, or Chatopleuraperwri- <in<i and C. henna hi, and (6) the thickened tooth-edges, which varies considerable in Mid>l, ndorffia and fails as a generic charac- ter in Ceratozona and some other groups.
It should be noted that in Middendorffia the true structure and especially the sculpturing of the girdle-scales often cannot be satis- factorily observed without a compound mici . nd a magnifi-
cation of Iron i ."in to MM) diain«'trr- is neC€80ary to deHMMIttntfl it iii many
N.CMVI :i:i :\ IMi. IM. 54, flg& 20
Shell oval, moderately elevated, not earinated, tin- ^ide slope* straight. Surtaee lii>t»-rl«s<, ur«'ii. -rally enerusted with ealrareous IT n> wths, gray or greenish blotched with Mack or dark green uitli some liirht marking or liirlit va!
The median valves arc beaked when young, but eroded and hardly beaked when adult, the lateral <i d lmt w>i
Itiftwo/inr iride rounded r/Ax with a shallow depression between them ; one rib diagonal, the other at the posterior border. Entire surface of all valves rrenh/ n>r> rc<! with comparatively coarse i/ru/iutes. Anterior valve having 8 or 9 low rounded radiating ribs. Posterior I'n /re very small, the mucro somewhat behind the center, the slope behind it straight ^posterior mart/in cni<i,-</in>if> (ai in Kudoxochiton, p. 193.)
Interior bluish in the middle, olive-greenish at the sides. $•' rather deep and amju/nr, t'trif jinnm* »/• .-•/"' ".'///• A more or less distinct laminate triangle extending from sinus to beak. Anterior valve having 8 or 9 slits corresponding in position to the external ribs ; the slits are very short, but are continued as grooves to the eaves outside ; median valves with 1 slit ; the anterior teeth nearly smooth, distinctly thickened or " propped" outside at the slits; pos- terior valve having slits, the teeth rather stumpy, short in the mid- dle behindj longer and directed forward at the sides. Eaves rather wide and coarsely spongy.
Girdle narrow, alternately dark and light, compactly covered with small, subcircular or irregularly polygonal scales, striated on the convex outer surface, crowded together; the margin beset with a series of slightly flattened, striated translucent bristles, (figs. 31, 33).
Length 14, breadth 8 mill.
Length 20, breadth 12 mill.
Entire Mediterranean and Adriatic Seas; Atlantic Ocean at Cadiz, Spain. Littoral zone.
Chiton i-'niereus (+ Lophi/rn.^ nnlphlctensis) POLI, Test. utr. Sicil. i, multivalvia p. 4, t. ?>, f. 1-20, (1791). Not C. eta Linn. — C. capreann SCACCHI, Cat. Conch. Regni Neapolitan!, p. 9 (1836) teste Monts. — C. caprearum Scac., BUG., DAUTZ. and DOI.I.- FUS, Moll. Mar. Rouss. i, p. 492, t. 61, f. 7-9 ; t. 62, f. 1 (1886).—
284 NUTTAI.I.INA.
Ch. polii PHIUI-IM, Knuni. Moll. Sicil. i, p. 106 (1836); ii, p. 83 (1844), and of most subsequent authors ; not Ch. polii Desh. 1832. — Ch. crenulatus LOCARD, Coq. Mar. des Cotes de France, p. 233. (1892), and perhaps C.erenulatusHiaQ Ear. Mend. p. 267. — Chiton TII-.KRI, Bull. Soc. Mai. Ital. iii, p. 141 (1877).— Chiton " Ki i :\ i: Conch. Icon., t. 28, f. 185 (1848).
Distinguished from other Mediterranean species by the finely granose- scaly sculpture covering the entire surface, with two low ribs at the lateral areas and 8 or 9 on the head-valve. The girdle is composed of short striated scales crowded together, producing a " cobble-stone pavement " surface. The true nature of the scales appears only when highly magnified. The nomenclature of the species is peculiarly involved, like that of most Mediterranean Chi- tons. Poli believed it to be the cinereus of Linnaeus, but Philippi dis- tinguished it from that and gave the name Polii, which unfor- tunately had been some years before bestowed by Deshayes upon another species. Monterosato claims to have identified it with Ch. eapreftrum (" caprearm ") of Scacchi, by examination of a type in the Petit collection ; but the description given by Scacchi is inadequate. Scacchi says : " Chiton caprearm [sic] Nobis. Clypeis 8 tuberculatis virescentibus, fascia marginali squamoso~muri<-'if<i, perbelle ciliata. Longus lin. 6, latns I in. 41. Caprearum scopulos incolit. '' Locard identifies it with crenulatus Risso, the original description of which follows: " C. crenulatus. Dorso segmentis omul- bus cinereis crenulatis, Long. 17 mill. Penn. Br. Zool. 4, JOTAT/, 3, Pol, 4, Hi. fn. Of course this may be the present species, but the wretched description, without a figure is quite unacceptable. Tiberi proposed the name Ch. decipiens as a substitute for polii Phil, not Desh. The locality of Reeve's Ch. corrni/ntiis is not known, but the description and figures render its identity reasonably certain, and Carpenter declares the types to be young polii Ph. In the midst of so many conflicting names and opinions I prefer to retain the name given by Poli. His description is infinitely better than any of the later ones mentioned above. Indeed Poll's work upon this species is wonderful for his time, and with such an example before them it is surprising that BO many Mediterranean naturalists have K-lt such miserable work.
It is needless to say that the Chitnn <-in, ,-, //., (}{' Limn' belongs to a genus which must be admitted by all naturalists who examine the subject, to be perfectly distinct.
• i: \-ri: 1 1 « .(in
The representation «»t' iln- course port- of tin- eavea in ti^. 28
cause- the toeth to :i|.|.r:ir pectinated, which i.- l.y IIM metDl tin- case. Vnr. ji.fwlnri**'! Cpr. Teeth <•!' insertion hardly thick, n,,| ;it the
edges; inucro Bubmedian ; Birdie scales elongated, flattened,
striated,
Matia.
The type is no. 51 of Mus. Cumin;:. (1arpenter, after examining more material, decided that this form was specifically identical with the Ch. poln Phil. His type specimen is a young shell. Not having seen it, I inn unable to tell whether all of the scales, or only those at the edge are elongated. In either case the subgeneric name Beania or Beanella falls as a synonym.
Genus XXV. CRASPEDOCHITON Shuttleworth, 18
Craspedochiton SHUTTLEW., Bern. Mittheil. 1853, p. 67. Type
C1//. laqneutits.
Valves exposed, slightly immersed, granulated ; with five low ribs on the head-valve ; insertion plates sharp-edged ; those of anterior valve long, strongly grooved inside and out, having slits at the positions of the external ribs ; median valves having the insertion plates thin, sharp, 1-slit; posterior valve with subcentral mucro, teeth short, grooved. Girdle corneous, very minutely roughened.
The characters of eaves and sinus are unknown to me. The external sculpture reminds one of Nuttallina, which differs in the posterior mucro, etc. The sharp-edged insertion plates, and the correspondence of slits to external ribs show clearly that this genus does not belong in the neigborhood of Chiton, Tonicia, etc., where Carpenter placed it, but with the genera here accompanying it which share these peculiarities.
C. LAQUEATUS Sowerby. PI. 39, figs. 42-51 ; pi. 44, fig. 68.
Shell ovate, depressed, granulated; pale, tawny or greenish, maculated with purple or green ; the dorsal rib purple.
Anterior valve having five low ribs, median valves squared at the ends, and having the sculpture often worn from the median ridge, which is wedge-shaped on each valve, the wedge being com- posed of about six truncated, somewhat wedged segments, and on each side there are oblique, irregular ridges. Posterior valve having the mucro central and very little raised.
286 ANGASIA.
Interior : . \nt.-rior valve (figs. 43, 44, 45) considerably thickened within, ;ui*l shallowly grooved radially ; the insertion plate stout at the base, acute at the edge, and furrowed both inside and out, the edge consequently being roughly crenulated; slits 5, corresponding in position to the external ribs. Median valves (figs. 46, 47, 48) havin.ir broad and thin insertion plates, which are smooth-edged, and only very finely striated. Posterior valve (figs. 49, 50, 51) having the insertion plate very short, thick, moderately sharp-edged coarsely grooved within and without, and roughly crenulated on the margin. AVhen viewed from above (the valve resting upon a flat surface) the teeth are not visible, and all touch the surface, there bi-in.ir n<> upward wave posteriorly.
Girdle coriaceous (or perhaps better, pithy) and almost smooth.
Length LSI, hivadth Hi mill.
Calapan, Island of Mindoro, Philippines, in coarse sand among small stones, in 9 fms. (Guming.)
Chiton laqueatus Sows., P. Z. S. 1841, p. 104.— REEVE, Conch. Icon., t. 20, f. 135.
The above description is mainly compiled from details furnished by Mr. E. A. Smith of the British Museum, who also drew figures 42 -51 from one of the original specimens. The scale-like granules are said to be represented somewhat too small on the figures. Sowerby remarks that the four or five central valves in several specimens are nearly covered by a dark purple color, the two last patched with green, and the first nearly white, but subject to some variations. Slmttlcuorth describes the girdle " limbus corneus, minuti atperulus," but Smith says it is nearly smooth in the British Museum specimens, and the insertion plates are visible through it, as shown in fig. 42.
Genus XXVI. A XGASIA Carpenter, 1882.
Angasia CPR., Table Reg. Chitons 1873 ; and in DALL, Proc. U. S. Nat. MusM 1881, p. 283, 286, 289, 290 (Jan. 20, 1882).— Augasia SCUDDER, Nomencl. Zool. p. 38 (typog. err).
Valves outwardly and within like those of Chwtopleura, but the eaves small ; girdle minutely scaly-pilose, and furnished with tufts of hairs at the sutures. Type A. tdrica Cpr.
I have seen no specimen of this form, which I believe to be related to Oraspedochiton, Carpenter writes as follo\\
287
"This genus difieif from c<i//i*(»i,/<i.>- in having the eaves nl.
the ttvth straight 'th-Hi-h i'iv.|nent ly |.n.|.prd oiit.-id.', a- in f ». the mantle en.udrd with minute Imni; and furnished wit 1. lichen round tin- -utiir<-<.
anterior valves is 5 slit, M in Aruntli"i-i,;t,--, hut that may be only a specific peculiarity. The 7A///A//./ variabiKt Ad. and Am'. I'. /.. 9 1-SI''I. p. 1!M, pn.hably belongs to this genus hut ha- not been dissected. Angasia is known at once from Hanlwja by the presence
of insertion teeth ; and from /'/,/,-/'/, /io/v/ hythe regular articular i-.n of the tail plate. If the genera be grouped according to the raanth- poivs Ant/'i*I'i will n-pn-sont Chatto/,/*,!,-,/ in the tufted series, as Callistoplax represents (.'<tt/!*t»rlitton."
A. TETRICA Carpenter, n. sp. PI. 61, figs 27-32 (sculpture not
represented.)
Shell oval, greenish-ashen, rather elevated, the jugum acute ; mucro slightly in front of the middle, slightly elevated ; valves squared, beaked ; the terminal ones much flattened. Jugular area obscurely tricostate ; lateral areas obscurely defined by a diagonal angle ; anterior valve somewhat obsoletely five-angled ; the whole surface very closely sculptured with wide, irregular, flattened some- times striated pebbles, smaller toward the dorsal ridge.
Interior: Posterior valve having 9-13 slits, the teeth small, radially flattened, rugose outside and propped, generally bilobate ; anterior valve having 5 slits, the teeth more acute, roughened out- side, slightly propped ; central valves with one slit, the teeth acute, rugose outside, conspicuously thickened or propped at the sides of the slit; eaves small; sinus narrow, short, smooth; sutural plates separated.
Girdle narrow, leathery, with very close and very minute cor- neous scales ; at the sutures and around the end valves there are bunches composed of a few short spicules, and there are a few scattered spicules also.
Length 15, breadth 9$ mill.; divergence 120° (C
Ceylon (Mus. Curaing, No. 83).
A. tetrica CPR. MS:, and in DALL, Proc. U. S. Nat Mus., 1881, p. 286 (no description).
A common observer might describe the mantle .simply as rough and leathery, so minute are its remarkable features. T
288 CALLISTOPLAX.
structure, l)ut \vitliout the purrs, characterizes some B '-rein
referred to r/m/i,y>/,-*//v<. The posterior valve somewhat reseml>lrs
an irregular M '•/ : the1 anterior valve is strictly Acanthochi-
toid. Both of tlu-se an- flatt< m-d, while the ridge is sharp on the .il valves. (Cpr.)
Yar. < AI.CULOSA Cpr.
Shell externally very similar to . 1 . tetrica, but roseate ; jugal areas distinctly tricostate ; anterior valve distinctly five-angled; pebble- sculpture smoother. Interior: posterior valve normal, with 5 slits, t la- teeth all acute, but slightly roughened, hardly propped; sinus narrow, deep, smooth, flat. Bunches of spicules minute, inconspic- uous (Cpr.)
J'/ti/ijijtitte* (Mus. Cuming no. 79, part.)
An(/'i.«in (/ tetrica war.') <-nl<-ul<>sa CPR., MS.
" The insertion plates of this shell offer a marked contrast to the Cingalese shell, being strictly like Ischnochiton (with shortened eaves) throughout. But one specimen, after an anterior fracture, has mended it with distinctly rugulose teeth, and made its posterior teeth propped and lobed, showing a close connexion between the tw<> forms. It is probable that Mr. Cuming''s specimens from the two localities had been intermixed. The tufts could scarcely be detected in shriveled specimens " (Cpr.}
Genus X XVII. CALLISTOPLAX Carpenter, 1882.
CPR., Table of Regular Chitons, 1873. — Dall, Proc. U. S. Nat. Mus. 1881, p. 283, 286 (Jan. 20, 1882).— TRYOX, Struct. and Syst. Conch, ii, p. 342.
Valves outwardly and within as in Callistochiton. Girdle naked except for a series of bristle-bearing pores.
The present genus is one of the very few which rest entirely upon characters of the girdle ; but so different is this from that of Callis- tnchiion. not only in the presence of pores, but in the entire absence of scales, that no course seems open but to treat the group as of generic value.
C. RETUSUS Sowerl>y. PI. fll, figs. 17-26.
Shell small, subeloniraU , -lightly elevated, the jugum acute; mucro median, vory obtuse, elevated in adult specimens. Jugal area smoothish, granulose, in the adult having a few acute longitu-
CAM BTOPLAJL '2*'.l
dinal linihe; central areas with about ID nigulo8e-gr:uio~e lit
each side, perpendicular to tin- diagonal line, the iut«-i--tic»-.- »-IIH-»-|-
lated. Lateral areas havini; two very strong rounded riln, the front one stronger, separated by a narrow sulc.us, and concentrically Wrinkle-graHOSe and very minutely ^ranulose; sutures \\ith a series of imbricating granules. Anterior valve having 7 ribs, of which the posterior ones (as in the median valves), bifurcate, and are imbricated along the sutures; posterior valve in the young shell having (I ribs, all of these bifurcate, and the anterior ones split twice, making 14 delicate, flattened ribs, which tend forward s what
Interior: the posterior valve, in a young specimen has about 11 slits, the teeth curved in harmony with the external ribs, and directed radially outward ; in the adult there are about 12 slits, the teeth solid, directed somewhat forward, rugose-costate at the mar- gins, concave in the middle, the eaves very heavily callous. Ante- rior valve having 7-8 slits, situated in the middle of the ribs, the teeth following the curvature of the outer margin, acute. Central valves with 1 slit, teeth excurved, eaves wide, pectinated, spongy. Sinus narrow, deep, narrowly slit on each side of the lamina, and sometimes denticulated by the external sculpture.
Girdle narrow, smooth, thin, having 40-53 bunches of long, cor- neous hairs around the margin, hardly sutural (figs. 23, 24).
Length 14*, breadth 8 mill.; divergence 120°.
Guacomayo and Puerto Portrero (Cuming) ; China Seas (Cum- ing.)
Chiton retmus SOWB. P. Z. 8. 1832, p. 28, Conch. Illustr. f. 22.— REEVE, Conch. Icon., t. 17, f. W.—Plaxiphora retusa H. & A. Ad. Genera Rec. Moll, i, p. 481. — Callistoplax retusa CPR. MS. and in Dall, Proc. U. S. Nat. Mus. 1881, p. 286.
The locality " China Seas " given by Cuming to Carpenter, is probably wrong, that originally given by Sowerby being much more worthy of confidence. The above description is from Carpenter's MS.
Figures 17-23 represent a young specimen ; in the adult the ribs become more numerous and the tail-plate more " Acanthoid " in appearance (figs. 25, 26).
19
290 CERATOZONA.
Genus X X VIII. CERATOZONA Dall, 1882.
Ceratopltnrus ('PR., Table of Regular Chitons, 1873, type C. iiuililinyi Rve. Not of Diesing, 1850. — Ceratozona DALL, Proc.U. 8, \;it. Mus. 1881, p. 283, 286 (Jan. 20, 1882).— Newcombia CPR., V\. type C.setosus Sowb. Not Neivcombia Pfr., Malak. Bl. i, p.
117. 1854.
Valves strong, exposed. Insertion plates of anterior valve long, sharp, rugose outside, thickened at the slits, which correspond in position to the external ribs ; median valves with similar propped teeth ; tail valve having the teeth thick, shorter, rugose, sinus solid. Girdle tough, bearing peculiar corneous spines, similar in substance to itself, generally sparsely bunched, at the sutures. The gills extend the entire length of the foot. Type C. guildingi Reeve = C. rugosa Sowb.
Shuttleworth may readily be excused for grouping the type of this genus in Chcetopleura. Compared with Ch. hennahi it is seen that both have the teeth sharp, and rugose outside ; both have the eaves solid or occasionally with a row of minute pores along the outer bases of the teeth ; and finally both have horny spinelets on the girdle. But in Ceratozona the insertion teeth are thickened at the slits which correspond in position to the riblets of the exterior ; the valves are much more firmly held in the tough girdle, and the appendages of the latter are much more deeply inserted in its sub- stance. If we examine an alcoholic example of Chcetopleura h> n/i'iJti we find that the cuticle of the girdle peels off readily, bringing with it all the spinelets, which leave shallow pits in the fleshy sub- stance of the girdle; but in Ceratozona, only the smaller hairs are thus readily removed, the larger ones being deeply and very intimately attached. Moreover, in most specimens, a pair, or a small bunch of spines, may be detected near each of the sutures ; but this character is often obscure or even wholly obsolete. From Nuttallina this group differs in the solidity of the sinus, the less pos- terior mucro, generally rugose and " propped " teeth, and the peculiar girdle-spines.
C. RUGOSA Sowerby. PI. 61, figs. 33-37, 41-45.
Shell oblong, rather convex, the back broadly arched. Surface generally much eroded, green, olive or slate-blackish on the sides, the central areas whitish along the middle, flamed with blackish at the sides, or green there; tail valve having a broad pink ray behind.
291
valves are strong, and when not eroded they are somewhat 'beaked. Lateral area- hardly raised, but defined !,y a Strong rounded rih, sometime- with a lower wide rib behind; having a sculpture of irregular wavy wrinkles over ribs and interval, and also upon the >ides of the cent nil area-. Head-valve having about 11 low radiating ribs and superlieially waved concentrically. Tail valve rather depre^ed with a siibcentral, slightly projecting mucro, the area behind it obsoletely radiated.
Interior blue-green, varying in intensity. Sutural plates moder- ate, separated by a rather wide smooth sinus. Anterior valve having 7-10 slits, the teeth long, acute, slightly rugose outside and denticulate at the edge, generally thickened or propped very strongly along the slits ; central valves with 1 slit, the teeth much thickened at the edges of the slit ; posterior valve having 8-10 slits, the teeth much shorter and blunter than in front, wedge-shaped, denticulate at the edge, not perceptibly propped or thickened along the slits, Eaves very narrow, having a single series of pores along the bases of the teeth.
Girdle very tenacious, rather wide, yellowish, armed with numer- ous corneous, yellow rather long and pointed spines, most numerous around the edge, and in most specimens showing a bunch of several at each suture ; among these larger spines, slender flexible beards are scattered (fig. 35).
Length 40, breadth 25 mill. ; generally smaller.
Jupiter Inlet, east coast of Florida (G. TV. Webster et a/.) to Jamaica (C. B. Ad., Johnson & Fox) ; Porto Rico (Blauner) ; St. Vincent and Trinidad (Guilding).
Chiton rugosus (Gray) SOWERBY, Conchol. Illustr. no. 6, fig. 49, (1841 ?).— REEVE, Conch. Icon., t. 18, f. 115 (April 1847).— Chiton (Chcetopleura) rugosa Sowb, SHUTTL., Bern. Mittheil. 1853, p. 78. — Chiton squalidiis C. B. Ad., Proc. Bost. Soc. Nat. Hist., ii, p. 8, (Jan. 1845). — Chiton gulldlngii REEVE, Conch. Icon., t. 21, f. 138 (May, 1847). — Cera^hoi'us guildingi CPR. — Ceratozona guildingi BALL, Catal. Mar. Moll., S. E. U. S. p. 172.— Ch. bicolor (C. B. Ad.) GRAY, P. Z. S. 1847, p. 67.
This species is not likely to be confused with any except the next. The valves are rather strong and blue-green inside, sometimes very pale. The girdle is of a conspicuous horny yellow color when scrubbed as in most cabinet specimens, but is dull and dark in the natural condition. The horny, curved bristles are both fine and
292 CERATOZONA.
coarse, but the more delicate ones are easily lost. The pore-bunches at the sutures are rarely conspicuous, and often cannot be made out without the aid of a lens and a lively imagination ; and this fact somewhat impairs their value as a generic character. Nearly all of the adult specimens I have seen are very much eroded.
Some recent authors have used the name guildingi Reeve, for this species ; it is not easy to see why, for Sowerby and Adams both preceded the author of the Iconica. The original figure of guildingi is copied on my plate, fig. 37. The sculpture varies a good deal. Fig. 36 is drawn from one of the most strongly sculptured speci- mens I have seen, from Jupiter Inlet, Fla. Fig. 34 is from Sta. Cruz., of the Virgin group, being drawn from a specimen colored exactly like Sowerby's original figure of rugosus (fig. 33). In this shell the teeth are less propped and the eaves narrower than in the Florida examples. Fig. 35 is from a Jamaica specimen.
I have seen no specimen with the mucro so posterior as it is shown in Carpenter's figure (fig. 41) ; all I have seen resemble fig. 39.
C. SETOSA Sowerby. PI. 61, figs. 40, 38, 39.
Shell oblong-oval, ashy-greenish, scabrous; front valve, lateral areas and posterior valve radially sulcate. Marginal ligament setose, the setae rather short and close.
Length 32$, breadth 15 mill. (Sowb).
Ouacomayoy Central America (Cuming).
Chiton setosus SOWB., P. Z. S. 1832, p. 27 ; Conch. Illustr. f. 19.— REEVE, Conch. Icon., f. 100. Not C. setosus Beechey's Voy. ' Blossom ' t. 41. f. 17,=Mopalia. Not Ch. setosus Tiles, Mem. Ac. S. Pet. ix, p. 484(1824).
This species is very distinct from C. setiger King, which it in some degree resembles. The bristles around the edge are much shorter, thicker and more closely set. (Sowb).
Carpenter has had figures of the interior and tail valve prepared, and I have copied them in my figs. 38, 39. I h#ve seen no species of this sort from the Pacific side of the isthmus, and I am therefore not prepared to say what relation setosa sustains toward rugo*a, the West Indian form. Fig. 40 is a copy of Sowerby's original figure of setosus.
MOl'AMII) I . 293
Family MOI'AIJ II>. K I'ilsbry.
(part • and .1/oy^/o/',/, ,, (part) C'l
Chitons in which the valves are divided in tin- normal manner into lateral and central areas; the teeth of insertion are not pectina- ted ; and the posterior valve has a posterior-median sinus, with one slit on each side or none. The girdle is more or less hairy, never scaly. (Jill row as long as the foot.
The normal number of slits in the anterior valve is 8 ; but this is often increased or diminished by splitting or fusion of one or two teeth. The slits correspond in position to external ribs, as in the last subfamily. In certain forms (Placiphorella, Placophoropsis) the number of anterior slits is abnormally multiplied. The inter- mediate and posterior valves have not more than 1 well developed slit on each side, and even this is lacking in the tail valve of Plaxi- phora.
The girdle clings more tenaciously to the teeth than in most chitons, being like that of Ceratozona. It is frequently provided with pores at the sutures, each pore generally bearing two or several bristles or hairs ; but the presence or absence of these pores is in no case of more than specific value, and in some cases I have found it to be a mutable feature among individuals of the same species.
The present family is in no manner identical with that so named by Dall, or with Carpenter's division of similar name ; nor is it in any sense equal to the Placophoridce of Dall, Placiphoroidea Cpr. These Carpenterian divisions of the " Irregular Chitons " are very artificial, just as the primary division of the group into " Regular" and " Irregular " forms is artificial.
The ancestors of Mopaliidce were Callistoplacince, probably not very different from the recent genus Ceratozona.
Key to the genera of Mopaliidce.
a. Posterior valve having a slit on each side of the median sinus. b. Shell oblong ; girdle narrower in front than at the sides, its hairs smooth ; teeth of insertion not lobed. MOPALIA. bb. Shell rounded-oval ; girdle expanded and broadest in front, its hairs scaly ; teeth of insertion more or less lobed.
PLACIPHORELLA. <za. Posterior valve having a median tail-sinus but no slits.
PLAXIPHORA.
294 MOPALIA.
Genus X X I X. MOPALIA Gray, 1847.
Mnjt,,lin OKAY, P. Z. S. 1847, pp. 65, 69, 169, (exclusive of sec- tion * *). Type Ch. hind*ii. — CARPENTER MS. and in Dall, Proc. U. S. Nat. Mus., 1878, p. 3Q3.—Molpalia GRAY, Guide Syst. Dist. Moll. B. M., p. 184 (err.typ.), 1857.— GOULD, Otia, p. 118.— 0*teoclriton DALL, Proc. U. S. Nat. Mus. 1886, p. 211. Type M. sin uata Cpr.
Valves normally proportioned, transverse, not beaked, exposed, the girdle somewhat encroaching at the sutures. Sinus small ; inser- tion-plate of anterior valve rather long, sharp, slit into nearly smooth teeth which are somewhat thickened at the edges of the slits, the latter being normally 8 in number and corresponding in position to external ribs. Median valves having similar 1-slit insertion- plates. Posterior valve depressed, the mucro post-median, insertion plate rather sharp, smooth or roughened, having an oblique slit on each side (rarely doubled) and a larger sinus in the middle behind. Girdle wider at the sides than in front, leathery, more or less hairy,, the hairs simple ; with or without sutural pores.
This genus is known only from the shores of the northern Pacific, extending from Lower California to Alaska and Japan. It may be regarded as the most primitive of the existing genera of Mopaliidce ; Placiphorella, and Plaxiphora being special modifications of the Mnfuilia type. The small additional slits occurring in some forms, such as M. acuta, are cases of partial reversion to the multifissate ancestral form which gave rise to the family.
Two species of Mopalia were placed by Carpenter in Placiphorella on account of their possessing sutural pores. Dall justly remarks that they differ from the true Placiphorellas, and he proposes Osteo- chiton as a section of that group for their reception. It is my belief that these species have no near alliance with Placiphorella, but that they are merely modified Mopalise. The gathering of a few hairs or spicules into a pore at the sutures is no uncommon occurrence, and in some cases (such as Ceratozona) it is not constant even as a speci- fic character. In Mopalia this modification will probably be found to occur in all the forms in which the girdle is nearly naked. In a small form of M. muscosa from Bolinas Bay the pores are sometimes present at all of the sutures, and sometimes at only two or three on one side, entirely absent on the other side. Sometimes they bear each a large hair, sometimes none. It is therefore obvious that we can make no disposition of Osteochiton except to consider it an absolute synonym <•!' M»},<dia.
'2'. ft
M. MU8C08A Gould. ri.i;.1!, ftgi, I'1. "al),fig». 49-63 (varr).
Shell oval, elevated <>r <l.-|.r«-.- ed, tin- d<T-al rid-i- UPTC OF \9U an-nlar. Valves strong. Sin-tare lotterlcM, lim-ly .-rulptiin-d with wavy, nvuulatrd lo^itudiiial rildeK .,1't. n OWN 01 let* obsolete. Color ireuerally dull hn.wn, Idaekish-olive or grayish, 1- times
bright orange, scarlet or vivid green.
Mrdian valves hardly braked, the lateral areas slightly raised, irranose, limited by a raised granose riblet. Central areas having close fine longitudinal riblets, with rrenulated or latticed int»-i>tices, the riblets finer and converging on the ridge of the last 6 valves, diverging on the second valve, or strongly diverging on the ridge of all valves, like a series of superimposed v's. Anterior valves having about 10 narrow radiating granose riblets, the intervals granose. Tail valve depressed with posterior mucro, the posterior slope very short, emarginate behind.
Interior bluish-green, stained with lilac on the central callus. Anterior valve having 8, median 1 short slit, the teeth long, deeply striated outside and thickened or propped outside at the sides of the slits. Posterior valve having a rounded sinus behind, with one oblique slit on each side, the plate roughened outside near the slits. Sutural plates broad, the sinus extremely shallow and small.
Girdle rather narrow, densely covered with round, curved or curled hairs. Gill row as long as the foot (pi. 64, fig. 74).
Length 52, breadth 38 mill.
Length 25-60, breadth 15-40 mill. ; divergence 120°-140°.
Shumagin Is. (rare) to San Diego, California, between tide marks and at lowest water.
Ch. muscoms GLD., Proc. Bost. Soc. N. H. ii, p. 145, July, 1846 ; Exped. Moll., p. 313, f. 436 ; Otia, p. 6.— Chiton dliatus REEVE Conch. Icon., t. 19, f. 124. — Mopalia ciliata H. & A. AD. Gen. Rec. Moll., i, p. 478.— DALL, Proc. U. S. Nat. Mus., 1878, p. 303 (syn- onymy and variation) ; p. 298, f. 35, 35a (dentition). NOT Ch. ciliatus Sowerby ! — Chiton setosus Sows, in Beechey's Voy. ' Blos- som' p. 150, t. 41, f. 17 (not C. setotus Sowb. 1832).— Ch. collei REEVE, Conch. Icon., t. 21, f. 136 (1847). — Ch. wosnessen*kii MIDD. Mai. Ross, i, p. 101 (part of diagnosis). — Chiton nnnatua NUTT., JAY'S Catalogue, 1839, no. 2678 (not described) ; Ch. aren- atus NUTT., in Mus. Acad. Nat. Sci. Philadelphia. — C. ornatus NUTT. MS. CPR., P. Z. S. 1855, p. 232.— and C. consimilis NUTTALL, MS. in Brit. Mus.
296 MOPALIA.
Iii its typical state (pi. 63, fig. 46), this species may lu- known by the stroug though variable sculpture, dull brown or blackish-olive color, the small sinus, the girdle being thickly set with round hairs varying from strong bristles to soft hairs. A variation in color is seen in some southern specimens (Tomales Bay) which are orange or scarlet (pi. 63, fig. 48), or yellowish maculated with orange and vermilion. Others from the same locality are vivid blue-green or green (pi. 63, fig. 47).
In his work on the Chitons of Alaska, Dr. W. H. Dall discusses the synonymy and variation of this species, concluding that M. lignosa Gld. should be regarded as an extreme form, connected by intermediate examples with the typical muscosa. He writes as fol- lows: "This species can be distinguished from all varieties of wossnessenskli by its blackish and proportionately much narrower girdle, and by a sort of prolongation of the external layer of the shell forward under the apex of the next anterior valve in the median line, forming a sort of anterior false apex, which is hidden until the valves are separated. In wossne*«enskli this part is squared off, the girdle is yellowish (when alive), and the valves are much less transverse. It will be surprising if those who have only observed these animals by a few dry specimens in collections are willing to accept the synonymy above given, I confess that not long since I would have been unwilling to believe that the rough, bristly, typical muscosa and the dark, smooth hindsii could be properly com- bined under one name with each other or with the finely reticulated and painted lignosa ; but the study of a large multitude of speci- mens has convinced me no arbitrary line can be drawn anywhere in a fully representative series, beginning with coarsest ciliata [muscosa] and ending with a practically smooth hind*ii. The characters of girdle, sculpture and form are not only variable in themselves, but are found variably combined, except that it is rarer to find coarsest sculpture with a downy than with a bristly girdle. However, even this occurs. On the other hand, out of such a series a dozen forms might be selected which, if only the characters were constant, every one would acknowledge as good species. "
Var. HINDSII (Sowb.) Reeve. PI. 62, figs. 99, 100; pi. 63, fig. 57.
Shell elongated and much depressed, (the angle of divergence about 140°), the girdle encroaching at the suture*. External color a light or dark shade of olive. Surface smoother than in typical
Morxi.i A.
the grtfiote-oorrugation b or lenzig-xagorcriit-
oi» tin- central arras, «il»li«jm-ly r..migated-grano8e on the
lateral aivas. /nt<ri<>r \rhil>\ "•/'//, «/<or< cr/'
; tail -inn- visiMr outside. (iinll.- with fi-w and .-hurt I.
hinil.<ii . Si,\vl». in Mus. Cuming) lii ndi. I«-.,n., t.
11'. f. 117.1, b (1847).— Mopnlin /ihul.«n ( i KA Y, I'. /. S. 1M7, pi 169.— II. it A. AD., Genera Rec. Moll, i, p. 478, iii, t. 54, f. 7.— MnjHtlia ritinta rur. Itindsii DALL, Proc. U.S. Nat. Mus. 187> 304.
The specimens described are from San Francisco Bay. The teg- mentum or outer layer of the valves projects forward somewhat at the sinus, as in typical nmscosa^ but this can be seen only in the detached valves.
Var. PORIFERA Pilsbry. PI. 62, figs. 93, 94.
Another form of muscosa, which if constant in its peculiar features would make an excellent new species of the section 0«teochiton, is before me from Boliuas Bay. It is perhaps deserving of a varietal name. The shell is rather small, thin and high, but not to as great an extent as M. acuta. It is sculptured as in M. hindsii, but the diagonal and sutural ribs are more prominent, and sculptured with strong, transverse beads exactly as in M. imporcata, the suture being dentated by them. Color of valves olivaceous, clouded obscurely with smoky, and having a black stripe each side of the dorsal lighter stripe. The posterior valve has a depressed mucro near the posterior margin, which is very slightly waved inward. Girdle firm and leathery, minutely and evenly papillose all over, blackish with spots of orange ; having a small pit or pore at each suture, with a series of pores alternating with these a little outside of the middle of the girdle (pi. 62, fig. 93). Sometimes some of the sutural pores bear large hairs, curling outward; and sometimes some or many of the pores are completely absent.
Length 23, breadth 13* mill.; divergence 105-115°.
The interior is a deep blue-green, or gray-blue \vith a purple-pink blush.
Var. ACUTA Carpenter. PL 64, figs. 75-81.
Shell rather small, strongly elevated, the dorsal ridge acute : valves thin ; sculpture minute and delicate, varying between a minute granulation and a fine pitting; the sutures delicately dentic-
298 MOPALIA.
ulate ; diagonal riblets obsolete or delicately raised. Color oliva- ceous obscurely mottled with dusky, the tail valve having a light ray behind.
Interior blue-green. Tail valve slightly waved upward in the middle behind, and having either a simple narrow caudal slit, or a slit with a small tooth set in its apex. Lateral slits of the tail valve generally double on one side. Girdle narrow, sparsely hairy.
Length 22*, breadth 12$ mill.; divergence 105° (Carpenter's type).
Length 22, breadth 13 mill. ; divergence 105° (San Diego spec.).
Length 23, breadth 15 mill.; divergence 98° (Sta. Barbara spec).
Santa Barbara (Canfield, Gabb.) ; San Diego (Hemphill).
Chiton acutusCpn., P. Z. S. 1855, p. 232.— Mopalia acuta CPR., Brit. Asso. Rep. 1863, p. 648. — Mopalia plumosa and M. (f var.) fissaCpR., MS. (? Not Ch.plumosus Gld).
The comparative tenuity of the highly angled valves, their deli- cate sculpturing over the whole surface, the fine denticulation of the sutures and the narrow, often toothed caudal sinus, all give an aspect of individuality to this form, and cause me to rank it with hind*ii and lignosa as a well-differentiated subspecies.
Carpenter, working from very few specimens, made three species of the forms of this. The occasional bi-slitting of the tail plate on one side is found also in some specimens of the elevated variety of lignosa from Olympia, Wash. It seems to me to be a very variable and trifling character. The caudal sinus seems to be indifferently narrowly slit or with a little denticle in the apex of the slit, and this little denticle also occurs sometimes in M. lignosa. The posterior valve has a narrow light triangle behind in all the specimens I have seen.
I have no hesitation in pronouncing plumosa and fissa absolute synonyms of acuta, but give here Carpenter's descriptions.
M. plumosa. Carpenter. (PI. 64, figs. 80, 81.) Shell oval, regu- lar, thin, elevated, the dorsal ridge acute, mucro behind the middle, depressed. Valves subquadrate, slightly beaked behind, hardly so in front. Olivaceous-ashen maculated with darker; central areas (with the scarcely defined jugal tracts) reticulated-porous, being sculptured with interlacing riblets forming quincuncially arranged impressed pits. Lateral areas defined but hardly elevated, sculp-
MOPAMA.
turnl with plumr-likr radii, granose at the SUtun -, t h.- «ii;iLr"iial ribs
and tin- radiating rililrts of the head-valve ; the grains elongated, siihspinose, elegantly strrntimj (fie sutures.
Interior pule blue. Tail valve having the p«.~t< Ti-.r linoi hardly indicated externally, xinof/, »/•/'//» <t minute toof/i 00J /// nf //«: apex; at one title it fut* "2, <it ike other 3 slits; slit-rays Inconspicuous. Central valves having 1, anterior valve 8 slits, the slit-rays con- spicuous; teeth acute, small. Eaves small, very spongy. Sinua s-iuall, deep, flat, the sutural plates separated.
Girdle thin, narrow, smooth, sparsely and irregularly beset with subtranslucent, larger and smaller tubular bristles.
Length 16i, width 11 mill. ; divergence 112°.
Habitat unknown.
The above description, from Carpenter's MS., was drawn from a single specimen in the collection of Dr. Wesley Newcomb (now of Cornell College). The figures 80, 81 represent the same specimen.
V&r.fissa Cpr. Sculpture between that of M. acuta and M. pin- mosa ; the granules at the suture and diagonal rib hardly claw- shaped; color and form also intermediate. Interior: posterior valve having two slits on one side, one on the other, the median caudal sinus minute, acutely slit ; otherwise normal. Girdle smooth with sparse, small spines.
Length 15, breath 10 mill. ; divergence 115°.
This form was described by Carpenter from a single specimen from Monterey. It differs from acuta and plumosa in lacking the "key-stone" like structure of the caudal sinus; but the series examined by me proves that this character has no constancy.
Subspecies M. LIGNOSA Gould. PL 63, figs. 58, 59 (typical) ; 60, 61, 62, 63.
Shell oval, elevated, carinated or angular at the dorsal ridge, the side-slopes straight. Surface lusterless, apparently smooth ; grayish, greenish or bluish with radiating streaks, lines and flammules of brown or purple-brown.
Under a lens the lateral areas appear nearly smooth ; the central areas being closely and finely pitted all over. Girdle narrow, sparsely hairy.
Interior white and light blue. Length 60, breadth 35 mill. ; divergence 120°.
Vancouver I. to Monterey, California.
300 MOP A LI A.
Chiton lignosus OLD., Proc. Boston Soc. N. H. ii, p. 142, (July, 1846) ; Otia Conch, p. 3 ; U. S. Expl. Exped., p. 330, f. 424.— •nplmrn li'jnosa GLD., Otia, p. 248. — Mojxilin lignosa CPR., Rep. Br. Asso. 1863, p. 648.— Chiton merckii MIDD., Bull. Imp. Acad. Sci. St. Petersb. vi, p. 20, 1846 ; Mai. Ross., i, p. 115, 1. 11, f. 5-6.— Ch. eschscholf:li MIDD., Bull. 1. c. p. 118, Mai. Ross., i, p. 114, t. 11, f. 4 (young shell). — Chiton mo/if< reyensi* CPR., P. Z. S. 1855, p. 231.— Chiton ve*pertinu* GLD., U. S. Expl. Exped. Moll. p. 323, t. 426, 426a (1852).— Chcetopleura respertina GLD., Otia, p. 230, 'l-\°l.—Mnpitl{« vespertina H. & A. AD., Gen. Rec. Moll, i, p. 479.— Mopalia rimptoni GRAY, P. Z. S. 1847, p. 69 ; H. & A. AD., Gen. p. 479; and Brit. Mus. Coll. (name only; never described. Type examined by Cpr). — Mopalia ciliata *•!</>.</>. lignosa Gld., DALL, Proc. U. S. Nat. Mus. 1878, p. 304.
Typically the M. lignosa is extremely unlike M. muscosa, but I am compelled to agree with Dall that there exist specimens completely uniting the two. A number of published names are above added to the long list of synonyms given by Dall (1. c.) ; and Ch. californicus (Nutt.) Reeve, which Dall includes, is removed, as it belongs to the genus Nuttallina.
The typical lignosa (figs. 58, 59) is exactly equal to merckii, to montereyensi*, and to the unpublished insigni* Newc. (fig. 63). It differs from the following form in the even puncturing of the sur- face (obsolete on lateral areas), the peculiar painting, and white interior.
The principal mutations of this type of Mopalia are (1). Toward still smoother forms entirely lacking pitted or reticulated sculpture, having only a few subobsolete longitudinal wrinkles on the ridge, the painting in concentric streaks (following growth marks) on each valve. This is shown in figs. 60, 61, of pi. 63, the specimen illus- trated being from Olympia, Washington. The C. vespertinti* of Gould is closely connected with this form, but is represented as typically much pitted (fig. 62). It is stained with crimson within.
(2). Form elevata (pi. 64, figs. 82, 83). More elevated, acutely carinated, more or less pitted superficially, and either painted with the pattern of typical lignox on a white, creamy or green ground, or having concentric zig-zag blackish streaks (fig. 82). Divergence about 90°. The interior is bright green or blue.
(3). Forms connecting with M. muscosa var. hi/i<l*ii, having the color pattern of //</ //••*./. but the sculpture intermediate in char-
• I- \l I \.
acter or quite like thai of /////•'' M. MIM.I MM>K! i ii Sehraick, I'l. ^2, figs. 88,89, 90,91,92.
Shell elevated. Coloration: a broad whitish area along the mid- dle, with transverse flainniules and lines «»!' mi-brown "ii tin- rl at th.' lidei concentrically and longitudinally painted \\ith r»-d- brown and whitish.
Median valves having the apex indistinct, the lateral JWM- «li- tinet. Kntire surface radially closely pitted, the pits very di.-tim-t over'the whole of the central areas, and in the middle of the lateral areas, but obsolete on the front and back edges of the latter. Anterior valve having 8 radiating riblets. Posterior valve slightly emarginate behind.
Interior roseate in the middle ; lateral slits distinct ; sinus shal- low. Anterior valve having 8, central 1, posterior two slits.
Girdle of moderate width, brown-red, setose, the setse irregularly and sparsely scattered, whitish, and about 3 mill, in length. Branchiae median, with about 36 branchial lamellae.
Length 14 mill. ; divergence about 115°.
Bay of Castries in 25 ft.
Chiton middendorffii SCHRENCK, Bull, de 1'Acad. des Sci. St. Petersb. iv, p. 408 ; Mel. Biol. iv, p. 89 ; Reisen und Forsch. in Amur-Lande, ii, Zool., p. 278, t. 12, f. 1-8 (1867).
A single specimen of this species was dredged by Schrenck, from whose account the above description is compiled. The sculpture strongly reminds one of some forms of Mopalia lignosa Gld., but the coloring differs markedly, and the habitats of the two are widely sundered.
M. IMPORCATA Carpenter. PL 62, fig. 98.
Shell small, oblong, strongly elevated and acutely carinated, the side-slopes straight. Buff-white, slightly stained ivith rust-brown.
The median valves are acute at the umbo, but there is no project- ing beak ; lateral areas bounded by a strongly elevated, narrow, crennltted diagonal rib, and having a wider rib at the sutural mar- gin, also crenulated, thus denticulating the suture ; the space between the two lateral ribs being finely corrugated-granose. Cen- tral areas sculptured with strong, curved longitudinal ribs, which converge forward somewhat, toward the median keel ; the intervals between these ribs being closely and finely latticed across by
MOPALIA.
threads radiating from the beaks. Anterior valve having 8 strong, nan .1 ribs, with one wider rib at each sutural edge.
Posterior valve depressed, the mucro situated at the posterior end.
Interior white; sinus very small and shallow. Anterior valve having 8, median 1 slit; teeth but little thickened along the slits. Posterior valve having a rather wide moderately deep rounded tail sinu>. and a single slit on each side.
Girdle leathery, dusty, with a hair-pore at each suture, and some scattered or alternating hairs.
Length 10, breadth 6 mill. ; divergence 95°.
J'lic/et Sound (Kennerley) ; Sta. Barbara (Cooper).
imporcata CPR., Proc. Acad. Nat. Sci. Phila., 1865, p. 59. — Placiphorella imporcata CPR., in Dall, Proc. U. S. Nat. Mus. 1878, p. 306.— Osteochiton imporcatus DALL, 1. c. 1886, p. 211.
This species closely resembles M. sinuata in size and sculpture. The two species differ in the following details : (a) M. imporcata is unicolored, while the other is elegantly marbled with blue and tawny; (6) imporcata has the sutural ribs more developed and very distinctly serrated, whilst in sinuata the serration is hardly appar- ent ; (c) imporcata has the longitudinal riblets of the central areas larger and the radiating threads which lattice their interstices much smaller and much closer ; and finally, (d) the tail valve in imporcata has an entirely posterior mucro, and a much shallower posterior sinus.
The girdles are the same in both species, being leathery, generally " dusty " in appearance in dried specimens, although scales are quite absent.
Thi> species might be considered a subspecies of M. muscosa were it not that it is smaller and more highly angled, of a uniform light color, and has the mucro farther to the rear. The girdle-pores at the sutures, and the entire sculpture are exactly like the pore-bear- ing variety of muscosa which I have above described from Bolinas Bay. It is very likely that the intervening links required to com- plete this chain of forms will he found.
The description and figures are drawn from Carpenter's type specimen, now in the U. S. National Museum.
The length is estimated in this and the following species, as the specimens are somewhat curled.
MO r A i.i A.
M. BIKUA1 \ Carpenter. IM. i\'2, BgS. 95, '."'•, 97.
Shell oblong, elevated Mini -tn.iiLrlv rannat--.!, the .-id,— . Straight. Color whitish, rfnmh-il //•//// fl,-/fc,i(r liliir.-yrr' n iiml , lated ii'ith rich ///»/•//// />/•»•//•//.
Median vulvos hardly braked, the lateral areas not raised, but strongly defined by an elevated diagonal rib; sculptured with two oblique series of fine riblets forming a latticed pattern. Central areas having a series of longitudinal curved rihlet.s eonveri:in'_r toward the median keel, crossed by curved radiating threads a little finer and less prominent (fig. 97). Anterior valve having 8 (not counting the posterior sutural borders) strong radiating ril is narrower than the latticed intervals. Posterior valve depressed, the •macro bcintj at the posterior third.
Interior bluish-white. Sinus very small and narrow. Anterior
valve having 8 slits, median 1 slit ; teeth thickened outside at the
edges of the slits. Posterior valve (fig. 96) having a deep rounded
infilinn shins behind (which is continued upward in a superficial
ition to the mucro), and a single slit on each side.
Girdle rather narrow, leathery, " dusty " bearing a few hairs, with a rounded pore at each suture (fig. 95).
Length 11*, breadth 7 mill.; divergence 105°.
Puget Sound (Keunerley) ; San Francisco Bay (Newcomb).
f Mopalia sinuata CPR., Proc. Acad. Nat. Sci. Phila., 1865, p. 59. — Placiphorella sinuata CPR., MS. and in DALL, Proc. U. S. Nat. Mus. 1878, p. 303, 306—Osteochiton sinuatus DALL, I c. 1886, p. 211.
This little species has the form and sculpture of the true Mopalias, but it differs from them in the posssesion of a bristle or hair-bearing pore at each of the sutures, the girdle elsewhere bearing sparsely scattered hairs on the leathery, minutely roughened surface. It resembles M. imporcata but is sufficiently different in sculpture.
My description and figures are from Carpenter's type specimen, now in the Smithsonian collection.
M. CILIATA Sowerby. PI. 64, figs. 64-73.
Shell oblong, rather depressed, the dorsal ridge carinated (some- times rounded), side-slopes straight or somewhat convex. Surface lusterless, finely sculptured, variously colored, usually either (1, typical coloring) verdigris green maculated with black or black- brown, the girdle yellow (fig. 65) or (2) maculated with maroon and sometimes touched with rich chestnut on the ridge, or having
304 MOPALIA.
some valves or parts of valves vivid scarlet (fig. 64), or scarlet mixed With olive and snow-white, or entirely white; or (3) light olive-buff with brownish girdle (fig. 67).
Valves somewhat beaked, the lateral areas bounded by a riblet, rather coarsely granulated, with larger granules along the posterior margin. Central areas sculptured with longitudinal, curving rib- lets somewhat granulated, much closer and finer on the dorsal ridge. Anterior valve having granose narrow radii, the intervals granulated. Posterior valve small, with posterior mucro, broadly emarginate or waved at the hinder margin.
Interior bluish-white or light blue-green. Sinus broad and rather rounded, -^pongy or roughened. Sutural plates arcuate. Anterior valve having 8 slits, median valves 1 slit. Posterior valve having a broad deep, rounded caudal sinus, and a single slit on each side.
Girdle wide, yellow or brown, generally notched behind, more or less sparsely clothed with curling strap-like brown /m //•>-, which bear near their bases a bunch of minute, ivhite, acute spines (fig. 66; the line below is 1 mill. long).
Length 46-50, breadth 25 mill.; divergence 125°. Unalaxhka, Aleutian Is. (small and rare) to Sitka, and tout I
I to Monterey, California; low water to 20 fms. on stones and shells.
Chiton d/lntus SOWERBY, Ann. and Mag. Nat. Hist. 1840, p. 289; Conch Illustr., f. 79 (1840). Not Chiton ciliatus Reeve, nor Moi»'li'i rilinta Dall. — Chiton wosnestemkii MIDD. Bull Acad. Imp. Sci. St.Pe"tersb. iv, p. 119, 1847.— Chiton (Hamachiton, Platysenuis) wosnessenskii MIDD., Mai. Ross., i, p. 34, 101, t. 11, tl-2.—MopaKa «rleyi CPR., Suppl. Rep. Brit. Asso. Adv. Sci. 1863, p. 648 ; Proc. Acad. Nat. Sci. Phila., 1865, p. 59. — M. (kennerleyi rar.) Swannii CPR., Ann. Mag. N. H. xiv, p. 426, 1864 ; Suppl. Rep. B. A. p. 648. — Mopalia grayi CPR., I.e. p. 603 (name only). — Mop" /in wos8ne8*cn.*kn Midd., BALL, Proc. U. S. Nat. M us. 1878, p. 305 (1879).
This species is distinguised from .17. IMUMOM and its immediate allies by its color; by the lack of that narrow anterior projection of the outer layer at the sinus, so conspicuous in the detached valves of the typical mu*cosa; by the encroachment of the wide gir- dle at the sutun-, the deeper caudal wave of the tail valve, and especially by the brom' ' it urn I plates.
IM.\< ii-ir<»i:i;i i \. :;or>
This last -or ins to be a constant character, and tin; prmliant the tail valve noticed above is also rcliahl.- ; l>nt i arhni.-nt
of the girdle at the sutures is seen al-> in .!/. Kindrii : tin- la<-k anterior projection or " false beak "is characteristic of many varie- ties of HI a. <r< >.<•!, such as the elevated var. of injiingn found at Olyin- pia, Washington, and the var. acuta Cpr. from southern ( 'ulifornia. The girdle covering presents a peculiarity not hitherto not! near the base of each of the curled brown hairs, there is a bunch of tiny white thorns or spines. These are also numerous at the edge of the girdle, which is seen slightly rolled upward in fig. 66.
Dr. Carpenter studied the specimens of" C. c/V////»/x " in ('inning's collection, and found them to be genuine w<< and therefore
Ball in his report on the Chitons of Alaska, as well as other Ameri- can writers, accepted the name ciliata in place of muscwft. Unfor- tunately, the Cumingian specimens are not the true ciliatu* of Sowerby, although described and figured as such by Reeve. The original C. ciliatus is identical with the small, green black-mottled form of " wosnessenskii " found at Monterey, etc.
An excessively rare monstrosity is shown in fig. 67, representing a seven-valved specimen, in which the reduced number is not due to injury or coalescence of valves, each valve being completely normal both outside and within. This figure, and figs. 64, 65, are drawn from Monterey Bay specimens. The sculpture (fig. 68) is stronger and sharper in typical ciliata than in the VB.T. wosnessenskii (fig. 72).
Var. WOSNESSENSKII Midd. PI. 64, figs. 69-73.
Shell elongated, the back roundly arched not carinated ; dull colored, varying from light olive or green to drab, generally with blackish patches on each side of the middle, and more or less mot- tled throughout with dusky. Sculpture much fainter than in ti/j)ic<il ciliata. Girdle apparently lacking the white spicules described above.
Sitka (Wosnessenski, figs. 69-71); Olympia, Washington (Hemp- hill, figs. 72, 73).
This seems to be recognizably distinct from the typical ciliata from Monterey, etc. American authors have hitherto given Wos- nessenski an s too many.
Genus XXX. PLACIPHORELLA Carpenter.
Placiphorella CPR., MS. in Ball, Proc. U. S. Nat. Mus. 1878, p. 303, 306. Type P. velata Cpr. 20
306 ri..U Il'IIORELLA.
Valve- very broad and short, tin- middle ones much broader than those toward the ends; head valve narrowly cresc-entic, tail valve still smaller, with interior mucro. Sinus small ; insertion-plates short and thick, the teeth lobed or rugose. Slits 8 or more in the anterior, 1 in the median, 2 in the posterior valve, which has also a shallow posterior sinus. Eaves spongy. Girdle widest, often very wi<le. in front, bearing sparsely scattered, scaled hairs.
This genus differs from Mojmlia in the rotund contour of the valves taken together, and their extreme shortness individually, as if the shell had been crowded together from the ends. The slits are practically as in Mopalia, being normally (or at least originally) 8 in the head valve ; but this number is frequently increased by the splitting of some teeth. The mantle-edge is produced in front and fringed with long fleshy finger-like processes. The larger hairs of the girdle are extremely peculiar, being covered with imbricating scales like a snake skin, on a corneous core. Nothing of the sort has been found in any other group of Chitons.
Carpenter originally intended this genus to include forms havim: hair-pores at the sutures, regardless of the other characters of valves and girdle ; but the presence of pores is not, in Placiphorella and M»j>'ilin,even a constant specific character.
The species are separated by rather slight characters and owing to the rarity of specimens in collections, we are not yet prepared to say to what extent the characters will hold good.
P. VI.I.ATA Carpenter, n. sp. PL 66, figs. 6-12.
- .ell roundly oval, broad, rather depressed, quite obtusely angled. Surface lusterless. Light colored along the middle, mainly oliva- ceous on the sides, especially the lateral areas; the central areas variou-ly streaked longitudinally with buff, blue, chestnut and pink.
Median valves not beaked, marked by growth lines ; the lateral areas somewhat raised, having a rounded wide diagonal rib and another at thesutural margin, the space between them more or less excavated. Central areas having a " false beak " or narrow pro- jection fonvard at the dorsal ridge (only visible when the valve- an* separated.) Anterior valve crescent shaped, sculptured with liirht concentric growth-lines only. Posterior valve small, slightly waved inward behind, the mucr<> >vard, recurred and elevated,
the slope in front of it concave in profile, unless the mucro is eroded.
PLA< ii'H'.i:i :
Interior white, slightly blur tinted. > sented by a very 8/t>il/>
fi;i a /t/ittr irliirl, jill.< the .S////M II h- a key-st<>' vii to viii tin- Him- i- derper and more <\\<\ inct I y angular, valve having* slit-, th'1 teeth ohtuse, short, often l.ilohed or COD- spieuously rugose. Central valves having 1 slit, teeth wedge-shaped, thicker at the edges of the slit. Posterior valve having a very heavy callus supporting the short, rugose insert ion-plate, which i- i n ten- n pted posteriorly by a broad, shallow sinus, and ha- 1 -lit on each side (occasionally two on one side).
Girdle very hroad in front, reddish, fading to yellow toward the outer edge, irregularly and sparsely beset with scaly hairs (fig. 13), of which one or two are generally to be seen in each suture ; a close fringe of short (broken) hairs adorns the girdle-edge.
Length 50, breadth 38 mill. ; divergence 135°.
Length 30, breadth 24 mill. ; divergence 130°.
Humboldt Bay (Newcomb) and Monterey Bay (Canfield, Hemp- hill, et. al.), California; Todos Santos Bay, Lower California (Hemp- hill).
Placiphorella velata CPR., MS.— DALL, Proc. U. S. Nat. MILS. 1878, p. 303, 307 (description of animal) ; p. 298, t. 2, f. 36, a (dentition).
This species is distinguished from the the next by its differently formed posterior valve, by the connection of the sutural plates across the sinus, and the anterior projection of the tegmentum at the sinus. The largest specimens I have seen were collected by Hemphill at Todos Santos Bay.
Fig. 12 represents the insertion-plates of an intermediate valve seen from their summits, showing the subtriangular form of the posterior insertion-tooth, the non-thickened edges of the slit, etc.
P. STIMPSONII Gould. PI. 62, figs. 84, 85, 86, 87.
Shell broadly oval, depressed, subangular, with straight side- slopes. Color whitish along the middle, the sides mottled and streaked with greenish-yellow, olive and blue, the colors so blended as to give a general effect of dark olivaceous.
Valves not beaked, sculptured with unequal growth-lines. Lateral areas having a moderately prominent diagonal rib, with an inconspicuous wider, lower, sutural rib, the space between excavated. Anterior valve narrowly crescentic, concentrically striated, but
308 PLACIPHORELLA.
lacking all radiating sculpture. Posterior valve (figs. 84, 85)- depressed, the mucro near the posterior margin, which is slightly and rather broadly waved inward.
Interior delicately blue-green tinted. Sinus a rather shallow rounded wave in the earlier valves, becoming deeper, narrower and angular in the eighth valve. Anterior valve having 8 slits, median valves having 1 slit on each side ; the eaves narrow, tenaciously adhering to the girdle.
Posterior valve small, its greatest width, including insertion and sutural-plates, measuring hardly more than one-half the width of the widest median valves ; the short posterior insertion-plate rising from a very heavy callous rim ; having one oblique slit on each side, and an almost imperceptible wave where the posterior sinus should be.
Girdle rather narrow, brown, leathery, sparsely beset with spinu- les (the stumps only remaining in the specimen before me), of which there is one at each suture and a marginal fringe.
Length 17, breadth 12* mill.; divergence 140°.
Hakodadi Bay, Japan (Stimpson), in 25 fms.
Chiton (Mopalia) stimpsoni GOULD, Proc. Bost. Soc. N. Hist., vii, p. 165 (1859) ; Otia Conch, p. 118.— Con/. DALL, U. S. Nat. Mus. 1886, p. 210.
The above description is from the type in the U. S. National Museum (no. 1646). It will be seen that the species differs from P. borealis in the smooth, not radially sculptured anterior valve, in the strongly calloused interior of the posterior valve, its shallower tail sinus, etc. The P. velata Cpr. of California has the valves very- similar to this species in form ; both differing widely from P. bore- alls in the solid, not spongy, sinus, partly filled by a short lamina connecting the sutural plates ; in the more calloused interior of the posterior valve and its smaller size ; the non-radiated anterior valve, etc.
Carpenter has given the following notes in his MS. on a fine specimen from Japan, in the Jeffreys collection. " As curled up and dried it measures, length 23, breadth 21 mill. ; divergence 120°. It is olivaceous and orange-ash variegated. Anterior valve smooth. Posterior valve having the mucro raised, at the posterior third, the sinus continued upward to it outside. Central valves with two obsolete but swollen ribs, one sutural, the other diagonal, with a broad depression between them. The girdle is very much shrivelled
PI . \. i ni' i :joi»
and the head rxpansion dotihled up, but tin- hair.- :in- very well preserved. Over the whol.- of tin- mar-innl p:t crowded deciduous whitish luiirs. Over the greater portion of the surface are scattered distant lar^e tnlndar, horny hair-, which seem to arise deep in the girdle. Th»>,- hairsan- not scaly an in I'. A///m- I'illti, l)Ut present when perfect the aspect of A«pr.nj HI" in i-'iyim'fcrum in miniature. I eann.it >ay with confidence that all the hairs are so sculptured, for some which look perfect do not show it. "
A. sketch made by Dr. Carpenter from a hair of this specimen is •copied on pi. 62, fig. 86. The. hairs on Gould's type are broken to very short stumps, not long enough to show their structure.
P. BOREALIS Pilsbry, n. sp. PI. 66, figs. 14, 15, 16, 17.
•
Shell similar in general characters to P. velata. Brown at the sides, light along the middle. Surface dull, showing growth- lines.
Valves not beaked, having a slight forward bend in the middle at the sinus, but not " false beaked " there as P. velata is. Lateral areas more strongly 2 ribbed. Anterior valve sculptured with numer- ous very low, wide radiating riblets. Posterior valve having the mucro near the posterior margin, depressed, the slope in front of it rising, convex rather than concave ; posterior margin waved inward.
Interior light blue-green. Sutural plates separated in all the valves by an angular, spongy sinus. Anterior valve having 11 slits, the teeth unequal, lobed or roughened. Median valves having one slit, the teeth being peculiar 1 1/ curbed outward at its edges. Posterior valve much less callous inside than that of P. velata, the insertion- plate uneven, roughened, but having a single well developed slit on each side ; the median tail-notch deep and wide. Eaves very spongy. Girdle unknown to me.
Breadth of anterior valve 16, length of front slope, including teeth 4J mill.
Breadth of a median valve 22, length from sinus to beak 4* mill.
Breadth of posterior valve 15, length direct from sinus to sinus 5 mill.
Divergence 135°. Measurements of breadth include the inser- tion-plates.
Bering Island, Bering Sea (Grebritzki).
Placiphorella stimpsoni DALL, (part), Proc.U.S. Nat.Mus. 1886
310 PLACIPHORELI.A.
p. 210. > uld.
This t'.»rm iskiiuwn to UK- liy tin1 valves of a single individual, no. uithsoniau register. It differs from P. vel-atn in the greater prominence of the lateral ribs, the curiously excurved teeth of the side insertion-plates (fig. 15), the less calloused interior of the posterior valve, and its very different form. Compare fig. 9 with riir. H>, the former representing the tail valve of P. velata, the latter that of P. borealis. Some other differences are indicated in the descriptions. In this specimen the slit on one side of the pos- terior valve is nearly obsolete.
P. BLAINVII.LII Broderip. PL 66, figs. 26-32.
Shell ovate, very broad, depressed ; variously clouded, streaked and maculated with rosaceous and olivaceous or red-brown, gener- al Iv tessellated at the sutures.
Median valves hardly beaked. Jugal areas sometimes defined by an obsolete v-shaped sulcus. Central areas appearing a trifle and most minutely granulate under a lens, otherwise smooth and shining. Lateral areas slightly swollen, concentrically marked by ribs of growth ; margins of valves rounded, the sutures not very deep except in young specimens. Posterior valve having the mucro pos- terior, almost terminal ; the posterior sinus of the valve wide and shallow.
Interior : anterior valve having 8 slits, the teeth rather short and roughened or crenulated outside. Posterior valve having a single slit on each side. Median valves with 1 slit; the sutural-plates rather straight and narrow, sinus a shallow wave.
( .irdle thin, very broadly expanded, in front, narrow and not sinuous behind. Surface having sparse, comparatively short hairs, which in drying become appressed on the girdle, each hair appearing scaly under the microscope, like a snake's skin (fig. 28). The hairs are not especially sutural in position, suture-pores being absent in adult examples ; nor do hairs occur in bunches anywhere. Besides these scaly hairs, there are scattered chaffy hairlets (which in one specimen more contracted than the rest are gathered into little bunches.)
Length 50, breadth 36 mill. ; divergence 147°.
Inner Lobos Island (Lobos de Tierra'), Peru, on stone in 17 fms. (Cuming.)
Chiton blain>;>/;; BltOD., I'. Z. S. \W, p. 27.— SOWERBY, Conch.
[PHOBB] i.\ PLAXIPH4 ••! 1
r. S. Ui i \ i . G uah. [oon., t, I, i'. i i/ GRAY, r. /.. U—Jfopafta !
J/\ MII.I in I) M.I,, Proa l'. 8, Nat. MUH. 1878, p. 303.— /
hUnmllii DAM,, /. c. 1886, p. 210, 21 1.
This lurm' sp.vir- i- nearly allied (.. /'. ,-. f<tta of ( 'alifornia, hut it diti'rrs in having the lateral areas simply x.nit-u hat swollen, and Dot excavated in tin- middle. Tin- sinus between the sutural plates is a shallow wave, lmt it deepens mi the two or three backward valves, as in the Californian species. The description iriven above is com- piled from Carpenter's notes on the type specimens.
P. I-I-:TASUS Reeve. PL 66, fig. 25 (enlarged.)
Shell small, somewhat abbreviately ovate. Valves with a polished, slightly beaked triangular area in the center, roughly granulated on each side. Bright scarlet. Ligament very broad, especially in front, also bright scarlet, beset here and there with short hairs and bristles.
Length 1, breadth 1 inch, (five.)
Cape Eivers, Celebes (Belcher.)
Chiton pet««u8 REEVE, P. Z. S. 1847, p. 25 ; Conch. Icon., t. ?6, no. 114, fig. 112, (not 112 on plate of details, nor 114) ; July, 1847. ADAMS & REEVE, Zool. of the Voy. H. M. S. 'Samarang/ Moll., t. 15, f. 11.
Referred to this genus on account of the peculiar girdle. A single specimen was collected. The characters of the interior have riot been made known.
Genus XXXI. PLAXIPHORA Gray, 1847.
Plaxiphora GRAY, P. Z. S. 1847, pp. 65, 68, 169.— SHUTTLES ., Bern. Mittheil. 1853, p. 69.— H. & A. ADAMS, Gen. Rec. Moll, i, p. 481.— Placiphora CPR., MS. and in DALL, Proc. U. S. Nat. Mus. 1881, p. 284.— Placophora DALL, Cat. Mar. Moll. S.-E. U. S., p. 1 74 ; not Placophorm Mulsant, 1873 (Trochilidce'). — Eupfaxiphora SHUT- TLEW., 1. c., (proposed for biramosus and petholatus). — Eiiplndphora CPR., /. c., (type P. petholatd). — Ch'jdopleura (part) ROCHEBRUNE, Miss. Sci. du Cap Horn, 1882-1883, vi, Zool., Polyplacophores, p. 135 (1889), not Chcetopleura Shuttlew. !
Valves mostly exposed, all having insertion-plates developed, that of the anterior valve normally with 8 (sometimes 7-9) slits (except in the subgeuus Placophoropsis which has many slits). Median valves 1 slit. Posterior valve having the insertion-plate smooth,
312 PLAXIPHORA.
;. interrupted behind by a median, rounded sinus, which does not generally enmrginate the tegmentum; mucro posterior. Girdle bearing simple bristles or hairs, scattered or gathered into pores or tufts at the sutures. Type Chiton setiger King.
This genus is most nearly allied to Mopalia and Placiphorella, from both of which it differs in the unslit insertion-plate of the tail valve. The peculiar girdle-bristles of Placiphorella are an additional char- acter separating the genera.
In Plaxiphora, as in Mopalia and Placiphorella, the bristles of the girdle are indifferently scattered or gathered into sutural bunches. This character is of specific value only when strongly developed ; and each of the three genera contain species which in occasional individuals develop pores, or species usually poriferous, but varying to poreless. This distinction, which Blainville, Gray and the Adams brothers considered fundamental, is therefore of comparatively tri- vial importance.
Plaxiphora is divisible into a number of minor groups, as follows:
Subgenus PLAXIPHORA (restricted.)
Slits of anterior valve normally 8 (sometimes 7 or 9 by coales- cence or splitting), coresponding in position to external ribs ; the teeth long outside. Girdle widest at the sides. Mantle not fringed in front of the head. Distribution, Southern extremities of the southern continents ; living in the littoral zone.
This subgeuus although rather homogeneous, may conveniently be divided into three sections, as follows : Section I. Plaxiphora, restricted (=Euplaciphora Shuttl. not Cpr.).
Valves exposed. Entire shell normal in form ; posterior valve
not greatly reduced in size or altered in form. Section II. Guildingia Cpr. Valves partially immersed in the
girdle, which encroaches at the sutures. Section III. Fremblya H. Ad. Valves exposed. Shell short and
broad ; the posterior valve reduced to a narrow crescentic form,
and seen to be strongly arched upward if viewed from behind.
Subgenus PLACOPHOROPSIS Pilsbry.
Slits of anterior valve numerous (about 20) ; teeth very short. Girdle widest and much dilated in front. Mantle produced into several long finger-like processes in front of the head. Distribution, Northwest Atlantic ; living in deep water.
i i .\\n-iroRA. 313
Subgenu- PI,A< <>i'ii<>i:<»rMs I'iMu-y, 1 893 (n. s.-g.)
Shell short, ol.Mvatr. t lit- valves short and \\ !<!<• ; li:i\ in;_r v almost obsolete insertion-plates, th:it of the anterior \:(l. many (about 20) shallow notches ; posterior valve with callous ridges at the sides and a shallow rounded caudal >inns. ( iirdle enormously liroadeiied in front, narrow In-hind.
This section is intcn liate between Placiphorella and P/'is!j>hora,
•differing from both and from and all M<i]m/iiil<r, in the multiplica- tion of anterior slits, although some specimens of Placiphorella show the same tendency. It must be understood that although in many groups of Chitons, such as all MinorhHoniinr and Chitonince, the number of anterior slits is a character of merely specific importance, the case is far otherwise in those groups in which the slits correspond in number and position with external ribs, such as Nutfallina and its allies, and the MnpnUldn , Acanthochitidce, etc. In these groups the number of slits in the anterior insertion-plate is a highly constant generic character, apparent exceptions being generally readily trace- able to the splitting of one or more primary teeth.
Besides the character just discussed, Placophoropsis resembles Placophorella in the form of the girdle ; but it differs in lacking Mopaloid slits in the posterior insertion plates. Placophoropsis resembles Plaxiphora in the non-slit posterior insertion-plate, but it differs in the obsolescence and multiple slitting of the anterior inser- tion plate, and in the anterior dilation of the girdle.
The obsolescence or shortness of the insertion-plates in this form is evidently due to degeneration from disuse. Deep sea Chitons not being subjected to the constantly recurring impacts and stresses which affect littoral forms, have no need of elaborate structures for binding the valves in their places. Consequently the primitive forms, such as Lepidopleurus, have been able to survive unaltered under these conditions. In the case of Placiphoropsis, which is descended from littoral forms having long, well-developed insertion plates, especially in the anterior and median valves, the shortness of the plates is to be ascribed to the absence of the external stimuli which act constantly upon the littoral Mopaliidce.
P. ATLANTICA Verrill & Smith. PL 66, figs. 18-24 ; pi. 65, figs, 73, 74, 75.
Shell obovate, wider in front, tapering toivard the small posterior valve, which is only about half as wide as the anterior valve. Rather
314 PLAXIPHORA.
depressed, roof-shaped, the dorsal ridge angular, side slopes slightly convex. Color pale brown, whitish along the middle and at the edge. Girdle extremely wide in front, narrow behind, dark brown in alcoholic specimens.
Median valves very wide and short, a trifle beaked in the middle- Lateral areas strongly elevated, the diagonal slope abrupt ; slightly excavated in the middle, obsoletely granulated. Central areas hav- ing rather inconspicuous growth-lines and an obsolete or nearly effaced granulation. Anterior valve very short and broad, having many faint radiating riblets and obsoletely granulated throughout. Posterior valve small, with posterior, slightly elevated mucro, and elevated postero-lateral ribs.
Interior white. Sinus very narrow, square. Insertion-plates very short, almost subobsolete, that of the anterior valve wide, calloused, having about 20 irregular and excessively shallow notches (hardly slits), obsolete toward the ends ; median valves with 1 slit. Poste- rior valve having a low wide callous ridge, slightly rugose, and in the middle interrupted by a shallow rounded sinus (pi. 65, figs. 73- 75.)
Girdle " very broad anteriorly and narrow posteriorly. It increases gradually from the posterior end to a point opposite the fifth plate, where it suddenly expands into a broad round front, with the breadth one-third greater than the greatest breadth of the shell. It is thick, leathery and scabrous, everywhere closely covered with minute spinules; the lower surface anteriorly showrs many radiating grooves (not distinct in the smaller examples) ; between these are rows of slightly raised small verruca, covered with small spinules. The inner edge, or mantle-border, is sharply defined, enclosing an elliptical area around the head and gills, with a well marked poste- rior sinus ; its front edge is divided into about seven digitations, the anterior ones rather long, tapering, and tentacle-like but coriaceous and covered with fine spinules, like the rest of the marginal mem- brane. Cephalic hood large, broad-lunate ; foot relatively small, ovate. Gills numerous (in the largest about sixteen on each side), extending nearly the whole length (more than two-thirds) of the foot, but reaching neither end of it."
Length of largest specimen (alcholic) 32, breadth 26 mill. ; length of shell 21, breadth 18 mill. Divergence 130°.
N. lot. 40° 01', Jr. I.,,,./. 68° 54', in MO f**^ off Nantueket bland, and in N. lat. 42° 15' 25", W. long. 65° 48' 40", in 122 /m«., off ^ »
.iriroRA.
(U. S. Fi>h < \ ll.aln..-s ', 1883.)
Placoph AiiM-r. JotHI
:ice xxiv, Nov., iw, p. :;•;.'» (fbotoot theC/oni
mt A. -ad. -my O/ Natural >.-i.-n.-, ,. vi. p. 2 f. 1. hi, 1 A. ^
1884).— Placophnrn <itl,mtic<i V. ,V S.. DM i.. Hull. :;7, U. S. Nat. Miis.. p. 171, t. l.», f. la, 6; t. 63, f. 102, 102a ( repp,diir-d ; Verrill & Smith.
A vt-ry peculiar species. The tiiruivs of tin- tail and head plates given by Verrill and copied on plate G«) are not very good, and I have therefore drawn others from one of the original specimens, on pi. 65.
The only specimen of this species which I have examined has a deep cleft in the posterior margin of the tegmentum of the tail valve, parallel to the lower border of the valve. Whether this is or is not abnormal must be decided by the examination of more material. It is well shown in fig. 74, of plate 65.
Subgenus PLAXIPHORA Gray. Under this subgenus three sections, defined above, are placed.
Section Plaxiphora Gray.
This section as here restricted corresponds to Gray's original genus, except that he was ignorant of the fact that sutural pores or tufts are absent in some species. It is absolutely equivalent to Shuttleworth's section Euplaxiphora, but Carpenter restricted this last name to species of the P. petholata type, having no pores or tufts at the sutures. The mutability of this character has been dis- cussed under Mopalia ; therefore it is necessary in this place merely to state that the presence of pores at the sutures is not even a con- stant specific character in Plaxiphora, except when the tufts are strongly developed. There are several species in which the pores are visible in some specimens, but quite absent in others preserved in the same way.
The corrugated Plaxiphoras are in great need of revision ; but the material now in museums is insufficient. Great latitude may be expected in the range of specific variation, as in the genus Mopalia.
Partial key to species of Plaxiphora. a. Central areas unsculptured save for growth-lines.
316 n.AxiriiORA.
6. Sutural pores or tufts distinctly developed; sinus shallow, c. Anterior valve distinctly ribbed ; lateral areas dis- tinct, setigcr, biramosa. cc. Anterior valve smooth ; lateral areas indistinct. Dark brown, banded with paler at the ridge,
simplex, bb. Sutural tufts or pores absent.
c. Lateral areas undefined, not sculptured.
d. Sinus deep, narrow, denticulate ; brown, with a yellow-bordered dorsal band of chestnut,
wahlbergi.
dd. Sinus wide, smooth ; black, with a green- bordered dorsal black triangle, glauca. cc. Lateral areas defined by a beaded rib, concentric- ally wrinkled.
d. Colors bright and variegated ; size small,
carpenteri. aa. Central areas corrugated, at least at the sides,
Group of P. petholata. Group of P. terminalit.
Group of P. setiger.
Shell smoothish ; girdle with distinct sutural pore-bunches. P. SETIGER King. PL 65, figs. 76, 77, 78, 79.
Shell elliptical, low roof-shaped, the ridge carinated, side-slopes straight. Surface lusterless, smooth except for delicate growth-lines. Color ashy-olive or bluish, with concentric dark streaks, and gener- ally having unequal stripes radiating from the beak of each valve, these markings varying from indistinct to conspicuous.
The median valves are not beaked. Lateral areas not raised, but clearly defined by a narrow, raised diagonal riblet, and perceptibly sivollen or ribbed toward the posterior margin, 'jiving the young a bicostate appearance ; the tiro ribs being more or less nodose, especially in yointg specimens, and toward the beaks in adults; and there are also a few extremely indistinct radiating riblets in the slightly excavated middle portion of the lateral areas. Central areas smooth. Anterior valve having about 8 narrow radiating riblets, becoming obsolete as they near the peripheral margin, but each ending in a
I'l \ XM'IIORA.
slight projretion there ; the interval -«.iii»- iinli-ti:
Posterior valve drpiv-nl, tin- muero inruii.-pinioiH and about at the posterior fourth ; posterior aiva ubsoletely radi:it<-ly ri!>
Interior light blue ^reen. Sinus small and shallow. Sutural plates low. Anterior valve having 8, central valves 1 slit; the slits short, continued in grooves to the eaves; teeth long, irregularly striated outside, thickest along the slits, sharp edged. Posterior valve having the insertion-plate long and stout at the sides, inter- rupted l>y a rounded sinus in the middle behind; its edge smooth, unslit. Eaves very narrow and very spongy.
Girdle rather wide, leathery, having at each suture a small pore bearing several long corneous bristles, and with one or two more or less irregular series of bristle-bearing pores on the surface of the girdle, and a more or less dense clothing of small soft hairs over its outer part.
Length 50, breadth 35 mill.; divergence 125-135°.
Chiton setiger KING, Zoological Journal v, p. 338 (1831). — Sow- ERBY, Conch. Illustr., f. 17 ; Zool. Beechey's Voy., pi. 40, f. 7 (bad). — REEVE, Conch. Icon. t. ix, f. 48a, t. xiv, f. 48c.— GOULD, U. S. Expl. Exped., Moll., p. 330, f. 425. — Plaxiphora carmichaelis GRAY, P. Z. S. 1847, p. 68, and subsequent writings, probably not Chiton carmichaelis GRAY, Spic. Zool. 1828. — Plaxiphora carmichaelis HADDON, Challenger Report, Polyplac., p. 32. — H. & A. AD., Gen. Rec. Moll, i, p. 481 ; iii, t. 55, f. 3. — Chcetopleura savatieri ROCHE- BRUNE, Bull. Soc. Philomathique de Paris, 1880-1881, p. 119; Miss. Sci. du Cap Horn, Polyplacophores, p. 135, t. 9, f. 3a, 3b. — Chwtopleura frigida ROCHEBR., Miss. Sci. du Cap Horn, p. 137, t. 9, f. 5a, 5b. (young shell.)
This is the only well-established species known to inhabit the extremity of South America. It will be readily recognized by the smoothness of the surface, strong diagonal rib, and generally well- defined sutural pores, each bearing several bristles. The variation in color is well-shown on the plate. The C. savatieri (pi. 67, figs. 41, 42), and C. frigida (pi. 67, figs. 39, 40) of Rochebrune are merely, it seems to me, individual mutations of setiger the last being a young shell. It will not escape the observant zoologist that the artist who drew the plate of Chitons illustrating Rochebrune's paper, did not see the lateral slits in the valves. One is likely to infer that the other characters may be equally erroneously represented.
Some authors have given Gray's name carmichaelis to this species ;
318 1'i.AxiriroRA.
hut this identification rests only upon the synonymy given in Gray's several lists. Waiving lor the moment the question as to the identity of the original mnnicJutelis with setiger, we notice that the rest of Gray's synonymy of this species is in several respects incor- rect. C. biramosut Quoy for instance, is not the same as *etiger ; and his list of Chitons shows a number of other errors of synonymy. It is not safe therefore to trust Gray's dictum in such matters ; and it may fairly he doubted whether the original cannirhaelis, which is described as being " scarcely keeled," one-half an inch long, etc., etc., is the same as the large, strongly carinated Ch. setiger. In any case, Gray's name should be ruled out on the score of faulty definition. The name setiger was acceptably defined ; the species correctly located by King; and it was sheer piracy on Gray's part to shift his name from some poor little half-inch Cape of Good Hope specimen to this fine large form from Cape Horn. The original description of carmichaelis is as follows:
Chiton carmichaelis Gray. Shell oblong, convex, scarcely keeled, smooth, bluish-brown streaked and lined with white ; front valves with distant rather broad radiating nodulose ribs; front and back margins of the lateral areze of the middle valves with a single similar rib ; hinder valve smooth. Margin scabrous, brown. Length £ an inch, breadth |. Icon. Wood, Cat. Suppl., 1. 1, f. 10. Inhab. Cape of Good Hope. Capt. Carmichael, Brit. Mus.
Chiton carmichaelis GRAY, Spicil. Zool. pt. 1, p. 6 (July 1, 1828). Not ritu-ijthnra carmichaelis GRAY, P. Z. S. 1847, pp. 68, 169.— P. carmichaelis GRAY, Guide Syst. Dist. Moll. B. M., p. 186.
Var. FRKMKI.YI Broderip. PI. 67, figs. 37, 38.
Shell oblong, flattened, olivaceous-brown, varied with whitish- green lines ; anterior valve with elevated subgranose rays ; inter- mediate valves angular at the sides, the lateral areas biradiate, rays subgranose, intervals longitudinally subsulcate. Girdle set with numerous short bristles.
Length If, breadth 1 inch. (Brod.}
Bay of Valparaiso (Cuming).
Chiton frembleii BROD., P. Z. S. 1832, p. 28.— C. setiger var. fremblii SOWB., Conch. Illustr., p. 7, f. 4. — Chcetopleura huhni ROCHEBRUNE, Miss. Cap Horn, Polyplac., p. 136, t. 9, f. 4 (1889.)
This differs from P. set'i<j< / in being somewhat wrinkled concentric- ally. I have not seen specimens. Broderip inserted an e in Frem-
319
l»ly's name, evidently by inadvertence.
The fiUMire~ represent ('. Imliui Uuchebr., which I l.dic identical. It is thus described :
r/i/r/o//A-//m h,ihni [pi. <I7, li;rs. 37, 38]. Shell broad-ovate, flat- tened, «>btusely carinated, violaceous-bluish, with spots and lines of brown irregularly distributed. Anterior valve rounded, with 10 radiating ribs. Posterior valve very small, elliptical, feebly beaked. Lateral areas of the median valves narrow, bounded by a beaded rib; central areas covered with deep concentric stria', and very minutely striated transversely. Girdle wide, brown, covered with tawny hairs. Length 48, breadth 35 mill. (Rochebrune.}
P. BIRAMOSA Quoy & Gaimard. PL 68, figs. 51-54.
Animal ovoid, elongated, flattened, valves very transverse, little elevated, forming a low arch, not carinated ; striated transversely in front. White or green with a circle of red-brown on each valve. The anterior valve has 9 teeth on its edge, the posterior valve none. The sutural laminre are not wide, and are separated only by a very obtuse sinus. The insertion plates are slit at the sides at usual. Inte- rior dull white.
Girdle nude, vivid red-brown, having two spaced series of rough, sparse and bifurcating hairs, the inner series contiguous to the valves, the other near the periphery of the girdle, which is also hairy. (§.<£(?.)
Length 45, breadth 31 mill.
Chiton birnmosus Q. & G., Voy. de FAstrol. Zool. iii, p. 378, t. 74, f. 12-16. — Plaxiphora biramosa Q. & G., HUTTON, Man. N. Z. Moll. 1880, p. 116 (translation of Quoy's diagnosis). — Acanthochcetes lii-iimosus HUTTON, Trans. N. Z. List, iv, p. 181 (incorrect descrip- tion, from Deshayes). — Pladphora superba CPR. MS.
The external form is noticeably different behind in the two individuals which we possess ; but the red color of this species and its two series of bifurcating spines will readily distinguish it. ( Q. & £.)
I believe the form which Carpenter described in MS. as P. is the same as Quoy and Gaimard's C. biramosus. Carpenter's description is as follows :
P. superba (pi. 68, figs. 55-61). Shell large, oval, elevated, the dorsal ridge acute ; mucro subposterior, little elevated. Reddish- olive, maculated with darker and paler. Valves nearly rectangular,
320 I'LAXIPIIORA.
but well indented at the sutures, having a " false apex " in front. Lateral areas having indistinct, subobsolete radiating riblets. Ante- rior valve subangled by 8 radii, which slightly undulate the peripheral margin; otherwise nearly smooth except for growth- lines. Interior : posterior valve having the insertion-plate elevated, rounded, interrupted in the middle behind by a very narrow, deep sinus. Anterior valve having 8, central valves 1 slit; teeth long,. slightly striated and slightly thickened at the edges of the slits out- side. Sinus narrow, short. Sutural laminae continuous over the ante- rior false apex. Girdle (fig. 61) tough ; black, leathery, hardly sinuated behind, smooth, with a few bristles at the sutures and around the margin.
Length 60, breadth 40 mill. ; divergence 110°.
New Zealand (Mus. Cum., no. 2.)
This very fine but unsculptured species was marked as new in Dr. Gould's collection, but not described by him. It is abnormal in the nearly smooth aspect of the tough girdle, in which however the binary pores (of which five surround the head valve) are distinctly marked. The shape of the valves is nearly as in Mopalia wosness- rnsk'd. (Cjpr.)
Professor Hutton has considered his Tonicia corticata a synonym of biramosa, in his Manual of New Zealand Mollusca, 1880 ; but the description (copied below) would hardly lead me to the same conclusion, although Hutton's species is undoubtedly a Plaxiphora* In sculpture it must resemble P. terminalis.
Tonicia corticata. Oval ; margin naked ; valves much depressed ; posterior margins slightly concave ; lateral areas bounded on each side by a flatly nodulose ridge, the space between being obliquely striated, the striae running outward and backward ; median areas rugose, without either distinct lines or granules. Length 1*25, breadth 1'13 inch. Color: margin black when dry; valves grey; inside white, covered over with white, coralline growth and small marine algse. Founded on a specimen in the Colonial Museum, locality not stated. (Hutton, in Trans. N. Z. Inst. iv, p. 180, May, 1872.)
P. SIMPLEX Carpenter. PI. 67, figs. 43, 44, 45, 46.
Shell similar to P. modesta, but more elevated, longer ; valves rude, maculated with brown-purple; dorsal ridge rounded; mucro posterior, flattened ; lateral areas scarcely defined ; valves rounded,
i-i \\M-HMI; L
with larjr -iitures. Entire .-m th, L'«'n<Tallv en. did. .~ul>-
spoiiL,ry. Interior; j.n>t. rior valve with a Hindu ah-iy ••!<• insertion-plate, moderately Miniated behind. Anterior valv v.itli *, median valves 1 slit; teeth acute, scarcely thicken, d at the .-d^es of
the slits. Kave> short, sj gy. Sinus very narrow, -niooth, straii'lit.
Girdle spongy, having very close, small hairlrts, and loiiLr<'i hairs scattered and at the sutures. (Q?r.)
Length 1-35, l>readth '7 inch, divergence 120°.
Var. : length 1*1, breadth •<;."> inch, divergence 100°.
Tristan Inland, Tristan da Cunha, on the shore, and off Nighten- gale Island, Tristan da, Cunha, 100-150 fms. ('Challenger.')
Euplaciphora simplex CPU., J/N. — P/axiphora simplex CPR., in Haddon's Report on the Polyplacophora of the Challenger Expedi- tion, p. 33. Also described by HADDON, I.e., p. 34, t. 3, f. I-'!, 13a-c.
This species I have not seen. The P. modesta alluded to by Car- penter is a form of P. petholata.
Haddon describes P. simplex as follows :
Shell smooth, simply marked with line of growth, flat sides meet- ing at a variable angle. Anterior valve small, surface smooth. Under surface with eight slits, teeth fairly long, smooth and sharp ; eaves short. Intermediate valve : Central area ; smooth, flat. Lateral areas inconspicuous, with two or three very faint radiating ridges. Under surface with a median horizontal rib-like swelling ; sutural laminae broad, but not deep ; jugal sinus wide and shallow ; one lateral slit ; eaves short. Posterior valve very small and flat, greatly corroded; umbo apparently flat and terminal; posterior border thickened. Under surface : sutural laminae as in intermediate valves, but the jugal sinus is comparatively narrow and deep ; slits and teeth absent ; posterior border much swollen.
Girdle very thick and fleshy, upper surface having a spongy appearance, owing to being beset with very short horny spines, which are scarcely raised above the surface; there are tufts of longer spines, three to nine in each tuft, opposite the sutures of the valves; these have no definite position round the anterior valve. Situated outside these are numerous scattered similar tufts, usually somewhat smaller in size, which pass into an imperfect peripheral fringe of spines, (pi. 67, figs. 44, 46). Color: all the valves of a uniform dark brown, with a pale (lilac) narrow triangular band along the
21
322 PLAXIPHORA.
juiriim of the intermediate valves (and anterior area of the posterior valve). Under surface of all the valves of a bluish-green color ; lamina? of insertion paler. Girdle, upper surface dark brown ; under surface dusky orange.
Length 40, breadth 25, height 10 mill. ; angle of divergence 125° to 135° (two specimens from 100 to 150 fathoms.)
Length 25 to 35, breadth 14 to 17, height 8 to 9 mill. ; angle 90° to 110° (two shore specimens.)
Group of P. wahlbergi.
No sculpture except some concentric lines; sinus deep, dentic- ulate ; girdle without sutural tufts.
P. WAHLBERGI Krauss. PI. 55, figs. 17, 18.
Shell ovate-oblong, slightly convex ; brown with a chestnut-brown median band and two yellowish longitudinal bands. Concentrically sulcate. Interior white, brownish-violet in the middle. Anterior valve semilunar ; posterior valve subtriangular, depressed ; inter- mediate valves subreniform, having distant concentric grooves on the front part of the central areas, and on the lateral areas. Girdle brown, leathery, velvety. Length 15, breadth 9 lines.
This species has rather thick, little convex valves, rounded on their outer ends, and having the older or posterior half of each eroded, and deprived of color and sculpture. Lateral areas not differentiated. The forward part and the sides of each valve have 6 or 7 separated, sometimes finely granulated furrows, parallel with the margins. The posterior margin is eroded, probably beaked in the middle. The insertion-plates are narrow, roughened outside. Anterior valve excavated behind, having 8 slits. Posterior valve lacking teeth. The valves have in the middle a chestnut-brown shining band, 2 mill, wide, on each side of which a yellow streak of greater or lesser width generally lies ; but usually they are eroded and gray. (Krauss.)
Table Bay, Cape of Good Hope.
Chiton wahlbergi KRAUSS, Die Sudafrik. Moll., p. 36, t. 3, f. 1 (1848). — Eupladphora wahlbergi CPR., MS.
May be known by the separated concentric grooves of lateral and central areas, parallel with the valve-margins, and also by the sinus, which is deep, narrow and denticulate, the last being an unusual character in this genus. The girdle has irregular setae.
I'l. AMPHORA.
Shell somewhat sculptured. (iinlh- covered with rri-p hair-, not forming bunches at tin- .-mures, nor having pores there.
P. PETHOLATA Bowerby, 1M. 68, figs. <L'. 68, ''.i 87,
Shell elliptical or oblong, rather depressed, the dorsal angle rounded but side-slopes rather straight. Surf ace finely corrugated at the nitl'*, nearly smooth in tin mi>l<lle. Color black or blue-black, with pink, creamy or greenish-white angular markings at the sides, and a wide triangle of the same light tint on the ridge of each valve, generally enclosing a dark, ill-defined dorsal stripe.
The median valves are slightly beaked. Lateral areas hardly raised, defined by a narrow, inconspicuous and slightly cum--! diagonal riblet, the surface finely corrugated in zig-zag or vermic- ulate pattern. Central areas corrugated zigzagly at the sides, in front of the diagonal ril>, th>- corrugation becoming fun. r toward the middle, and giving place to a microscopic pattern resembling a dense punctula- tion united with a minute zigzag or vermiculate wrinkling. Anterior valve having about 9 narrow radiating riblets, the intervals densely and finely zigzag-punctate. Posterior valve depressed, wide and short, the mucro at the posterior edge, slightly acute and a little elevated ; posterior area of the valve very narrow, ill-defined.
Interior dark blue-green. Sinus deep, uide, angular, its edge light brown and very spongy. Anterior valve having 8 slits, correspond- ing to external riblets, central valves 1 slit ; the teeth acute, some- what thickened at the edges of the slits. Posterior valve having a rather blunt, smooth insertion plate, interrupted by a shallow sinus in the middle behind. Eaves very narrow, spongy.
Girdle rather wide, black-brown and brown alternately, rather densely clothed with corneous or dark brown bristles, large and small, not in the least arranged in series or issuing from sutural pores.
Length 40, breadth 27 mill.; divergence 125°.
Length 32, breadth 18 mill. ; divergence 130°.
Length 45, breadth 25 mill.
Australia (Sowb.) ; Tasmania (Cuming.)
Chiton petholatiis SOWB., Mag. of Nat. Hist. New Series, iv, p. 289 (May, 1840) ; Conchol. Illustr., f. b'4, 65, and var. porphi/ri,'*, f. 59. — REEVE, Conch. Icon., f. 74. — fctijilm'ijJtnra petholata CPR., MS. Not Plaxiphora petholata ANGAS, P. Z. S. 1865, p. 187 and
324 r i. AMPHORA.
1867, p. 224.— Eitptadpl'ora modesta CPR., MS.
The sinus is squared, and the internal layer is bevelled off expos- ing the. very porous outer layer as in Nuttallina. Back of this porous area, the width of which varies, the surface shows transverse cuts or puncture-slits. The hairs of the girdle show no trace what- ever of arrangement in tufts or pores. The exterior is finely sculpt- ured with zigzag wrinkles, and the diagonal riblets on each valve, as well as the radii on the head valve, may be either nearly smooth or closely granose. The pattern of coloring is characteristic- but still quite variable.
Var. CONSPERSA Adams & Angas.
Shell oval, little elevated, with obtuse dorsal ridge. Ashy, with a few scattered clouds of dark and olivaceous.
Valves squared, thin ; apices not conspicuous, jugal areas marked off by slight indentations which are slightly divergent; but other- wise finely sculptured like the rest of the middle part of the central areas ; pleura having about 20 irregularly roughened line on each side, the line mainly forming right angles with the diagonal rib, but branching and minutely undulating ; becoming very fine toward and upon the jugum ; interstices very small. Lateral areas with the diagonal rib much elevated, rendered nodulous by the wrinkles pass- ing over it ; the same sculpture extending across the lateral areas and becoming more nodulous at the suture. Anterior valve having 8 ribs, besides those at the sutures. Posterior valve having the mucro at the posterior fourth, and with two diagonal ribs.
Interior : anterior valve having 8 slits, median valves 1 slit, corre- sponding to the external ribs ; the teeth slightly thickened at the edges of the slits. The posterior valve has well developed, sharp insertion-plates on each side.
Girdle pale brown, maculated with black-brown ; bearing fine, sparsely scattered soft corneous hairs.
Length 21-22, breadth 12-14 mill., divergence 117°.
Port Lincoln, South Australia, under rocks (Angas.)
Chcetopleura conspersa AD. & ANO., P. Z. S. 1864, p. 193. — ANGAS, P. Z. S. 1865, p. ISl.—l'laciphora conspersa CPR., J/\
I have seen no specimens of this form, which Carpenter believed to be a variety of P. petholata. The above description is from Car- penter's MS., and was drawn from Angas' type.
i-i AXii-noi: v. P. CAI:I-I MI to lla.l.lon. I'l. o7, Bgl 8
Shell smooth, the lidef meeting al an angli . Ant-
valve with riirht radiating ridges, not counting the swollen po-t Itonlrrs. Numerous n.n.vnt ri<- miii..r ridges cause these ridges to be rugose. Under iUrfftOQ \\ith nine slits, two 1 »• -ing very close toget eaves sliort.
Intermediate valves: central area smooth, with tin.- linos of growth ; no distinct keel. Lateral areas prominent, concentrically rugose, with a beaded ridire aloiiLr tlic anterior border, and, to a less extent, along the posterior border. Under surface with a median hori- zontal rib-like swelling; sutural lamina broad, but not deep ; ju.iral sinus shallow ; one lateral slit ; eaves short. Posterior : valve anterior area so large as to reduce the posterior area to a minimum ; smooth ; umbo minute, nearly terminal. Posterior area merely forms a con- centrically grooved thickening of the posterior border of the valve- Under surface : sutural lamina? as before, but the jugal sinus is com- paratively narrow and deep ; slits and teeth absent ; the posterior border is greatly swollen.
Girdle closely beset with very minute horny spines. The specimen had been dried when I received it, and none of the longer spines, characteristic of other species, are observable ; but I think I can discern traces of small sutural tufts.
Color : anterior valve with a median triangular area, with the apex at the umbo, is of a kind of chocolate color, which is variegated with minute zigzag grey lines ; the lateral spaces are of a dark slate color. Intermediate valves: central area: jugum pink; greenish toward the umbo when worn down. Pleura dark greenish-brown, with irregular longitudinal green bands. Lateral areas madder brown, blotched with brown. Posterior valve : anterior area resem- bling the central areas ; posterior border pinkish. Under surface of all the valves pale bluish green ; lamina? of insertion white. Girdle reddish-brown.
Length 14, breadth 9 mill. ; height 4 mill. (Haddon.)
Tristan da Cuntm.
Plaxiphora carpenteri HADDON, Challenger Rep. Polyplac., p. 34, t. l,f. 8; t. 3, f. 8«-</.
The sculpture of the shell, slight as it is, is sufficient to character- ize this species. (Haddon.)
P. OLAUCA Quoy & Gaimard. PI. 68, figs. 68-72.
Animal oval, widened at the sides. Valves wide, rounded, little
326 i-i.AxirnoRA.
elevated, subtriangular. uniform and smooth except toward the anterior margins where they are marked with three or four mar- ginal strije; they are black toward the lateral margins, with a tri- angle of the same color in the middle, bordered with yellowish or greenish.
Inside they are of a beautiful emerald green, the sutural laminae being of the same color and separated by a wide sinus. The anterior valve has its margin cut into 9 smooth teeth. Posterior valve hav- ing a semi-circular ridge in place of the teeth. The valves taken together form an elongated oval. All of the intermediate valves have one slit and two transverse striae on the apophyses.
Girdle of a beautiful light green, covered with rigid but not acute bristles of the same color. ( Q. & (?.)
Length 50, breadth 37 mill.
d' Entrecasteaux Channel, Tasmania.
Chiton glaucns Q. & G., Voy. de 1'Astrol. Zool. iii, p. 376, t. 74, f. 7-11 (1834). Not Chiton glaucus GRAY, an undetermined species, see p. 172.—lPlaxiphora ciliata ANGAS, P. Z. S. 1865, p. 187, not Chiton ciliatus SOWB.
This species is evidently allied to P. petholata. It is probably the form Angas collected at Guichen Bay, South Australia, and listed as " P. ciliata" He found it on rocks at low water, and remarks that it is the largest of the South-Australian Chitonidse.
Group of P. terminalis.
Sculpture stronger than in P. petholata. Girdle generally with more or less distinct sutural pores. Distribution, New Zealand.
P. TERMINALIS (Cpr.) Smith. PI. 51, fig. 14.
Shell resembling P. petholata in sculpture, but more elevated, longer, the mucro entirely terminal, produced. Dorsal ridge striped with white. Sculpture much more distinct, consisting of irregularly zigzag wrinkles all over, coarser at the sides.
Interior having 8 slits in the anterior, 1 in the median valves. Posterior valve with subplanate insertion plate ; the subjugal area punctate, teeth, sinus and eaves as in 7'. ji'tholata. Girdle having bunches of long horny hairs at the sutures and around the margin, elsewhere smoother.
Length 25, breadth 12* mill. ; divergence 120°. (Cpr.)
New Zealand (Cuming.)
PLAXIPHOHA. 327
ri<t.rii>hor« fernt in<i/i.< ( Vi:.. .)/>'. in M IH. ( 'inning. — f'liifnn ( Ttaxi- l»horn') trrminn/i* K. A. SMITH, \'.,y. Kn-biis and Terror, Moll., p. 4, t. 1, f. 13 (1874).— riajcljJiom t'TminnIi* Smith, HUTK-.V, Man. N. /. Moll. 1880, p. 116 (reprinted from Smith.)
Smith lias described this species in detail, as follows: "Shell elongately »>\ate, rather elevated, roundly angled along the top of the valves, black or bluish-black, with a white wedge-shaped stripe with a black one within it down the centre of the valves, forming a continuous white stripe divided by the black one along the center of the shell, in some specimens with a few short white dashes diverg- ing from the radiating ridges. The intermediate valves mucronated, bisected on each side by one raised radiating rib, the posterior mar- gins sinuated and thickened by coarse concentric lamellae ; the entire surface is covered with minute striate-wrinkiing, those near the ridge being coarser than the rest and radiating from it like the webs from the shaft of a feather. The posterior terminal valve has the mucro quite terminal. The anterior valve radiately eight-ribbed (at times one or two additional minor ones are present) with diverging oblique striations on each side of them. Interior of valves greenish- blue ; valve lobes whitish, the sinus between them deep ; the hairs or bristles on the mantle-margin are short, few and horny, those arising from the nine pores being thicker than the rest.
" Largest specimen (in a contracted state) 42 mill, long ; width of valves, 20 mill. ; an average specimen, length 25 mill.; width 11 mill.
New Zealand (Col. Bolton and Capt. Stokes.)
" Terminalis " appears to be but a manscript name attached to some specimens in the Cumingian collection. As I understand that Dr. P. P. Carpenter is engaged on a work on Chitonidcel retain the characteristic name he imposes. The central white stripe with the black one within it appears to be very constant."
Carpenter gave the varietal name zigzag, (in MS.) to specimens in the Cuming collection (no. 31) having stronger sculpture, one more anterior riblet, etc. It seems to be, merely an individual variation.
P. EXCURVATA Carpenter, n. sp.
Shell elongated, elevated, the dorsal ridge rounded, valves angled at the sides, obtusely beaked, the sutures indented. Irregularly maculated with coppery green and black.
Lateral areas defined by an obtuse curved rib ; toward the rib on
328 PLAXIPHORA.
each side closely concentrically sulculate. Anterior valve having about 7 or 8 ribs, sometimes with some intercalated subobsolete riblets. Posterior valve small, the mucro subposterior, swollen.
Interior blue. Anterior valve having 7-8, median valves 1 slit; teeth long, acute, scarcely thickened at edges of the slits. Posterior valve having an obtuse insertion plate, a little sinuated in the middle behind. Sinus broad, straight, spongy.
Girdle wide, thin, hardly sinuated behind, tessellated with brown and ashy, beset all over with sparse, delicate, short setae, longer at Ihe sutures.
Length 70, breadth 39 mill.; divergence about 110°.
Australia? (Haines Coll., and Coll. McGill University, Mon- treal.) .
Euplaciphora excurvata CPR., MS.
This shell has a general external resemblance in size and shape to P. cuprea, from which it is known at once by the color and sculpture outside, by having no posterior slit in the girdle, and inside by the smoothness and sharpness of the insertion-plates. It also resembles P. superba, but is entirely destitute of sutural pores.
P. CJKLATA Reeve. PI. 58, figs. 21, 22.
Shell oblong-ovate, somewhat attenuated anteriorly, terminal valves (the posterior of which is small and slanting) and lateral areas of the rest broad-ribbed and neatly carved with close-set waved lamina? ; central areas very minutely reticulated. Beautifully orna- mented with green and pink. Ligament horny, here and there bristly. (Reeve.)
New Zealand (Earl, Cuming.)
Chiton ccelatu* Rv., Conch. Icon., t. 17, f. 101 (1847).— Strepto- chiton cupreiis CPR., MS., olim. — ? Tonicia zigzag HUTTON, Trans. N. Z. Inst. iv, p. 181 (1872.)
The verdigris green and peculiar pink color-pattern is character- istic and singularly beautiful.
Von Martens has stated that Tonicia zigzag Hutton is a synonym of " Acanthopleura " ccelata Rv. (Crit. Cat., p. 49) ; a conclusion accepted by Hutton (Man. N. Z. Moll., p. 115, 1880). As in other cases of alleged identity, the original type of zigzag should be re-examined. Button's description is as follows :
Tonicia zigzag Hutton. Oblong; mantle slightly tomentose; valves slightly flattened on each side, but not keeled; posterior
ri. \\irn
margins >lopin«r harkwanU into a point, rrennlated on !. anterior valve with !' radiatim: rid -.:»•- >iie concc-i.
zig-zag stria*; lateral areas with two, on <-:i< I ulges
crossed by line zig-zag stria- ; pOtterioi and median ar«-;is with fine oblique stria- divrr-m'j- t'n.ni the dorsal line out ward ami tor
Md by others divrririni: outward and buekward forniing an en-ine turned pattern. Length 88 inch. ; breadth .'51 inch.
Color, mantle white; vakvs .irivyisli-blark with a white -tripe on each side of the dorsal line ; interior Lrreenish-Une.
A single specimen is in the ( 'olonial Museum, locality Dot st:r (Button.)
The following species probably belongs here, but I have seen no specimen, and it has not been figured.
CHITON (CH.ETOPLEURA) PLUMOSUS Gould.
Shell brown-ashy, valves concave scarcely beaked ; anterior valve ornamented with plumose radiating line; posterior valve small, the apex marginal and having a submarginal rib on each side. Central area large, ornamented with divaricating stria?, and lateral plumosely co-united striae. Lateral areas small, bounded by asutural rib, striae denticulated, interspaces clathrate. Girdle broad, leathery, furnished with (bristly?) tubules.
Length I'D, breadth '75 inch. (Old.)
Habit'tt tnil-n
Allied to C. ccelatu* Kv., which is said to be highly ornamented with green and pink. (7. collei and C. mmcosus G. belong to the same group. (Old., in Proc. Bost. Soc. Nat. Hist, vii, p. 165.)
Section Guildingia Cpr., 1893, n. sect. .
Guildwyia CPR., MS., and in Dall, Proc. U. S. Nat. Mus. 1881, pp. 284, 288 (type G. obtecta Cpr. MS.)
Shell and girdle like Plaxiphora, except that the valves are partly immersed by the encroachment of the girdle.
This section, like Fannettia in the genus Toniria, rests upon a character of very little taxonomic value ; but as it is useful in break- ing up a large genus for convenience in identifying, it has been retained.
330 PLAXIPHORA.
P. OBTECTA Carpenter, n. sp.
Shell large, broad, partly covered. Valves smooth, most minutely punctulate angulate in front ; sutural sinus large, produced forward over the jugum ; lateral areas scarcely defined except by an angle at the forward outer margin of the valves ; dorsal ridge rounded. Intense olivaceous, paler on the dorsal ridge. Mucro of posterior valve terminal hardly produced.
Interior : posterior valve with flattened insertion-plates. Anterior valve with 8, central valves 1 slit ; teeth very acute, long, smooth, a little thickened at the slit-edges ; eaves narrow, spongy. Sinus deep, very obtusely angular, with a spongy area. Sutural laminae long, separated. Girdle very broad, sinuated behind, with bundles of about three large, horn-like hairs at the sutures, and having smaller ones sparsely scattered all over more or less closely. ( Opr.}
Length 50, breadth 32 mill.; divergence 120.°
New Zealand (Mus. Cum., no. 45.)
This very interesting shell differs from the typical Plaxiphorw as Fanneltia does from Tonicia. It is, however, simply an exaggera- tion of P. terminalis.
Section Fremblya H. Adams, 1866.
Frembleya H. AD., P. Z. S. 1866, p. 445. Type F. egregia H. AD.— Fremblya CPU., MS. and in Proc. U. S. Nat. Mus. 1881, p. 284. — Streptochiton CPR., MS. olim.
Shell and girdle like Plaxiphora except that the former is short and broad, the tail valve very much reduced in size, strongly arched upward in the middle behind. Slits in intermediate valves poste- riorly situated. Girdle having more or less obvious sutural pores.
The sculpture of these forms is like that of the more elaborately carved Plaxiphoras of the same regions; but the considerable modification in the general form of the tail valve may be held to be sufficient ground for the retention of Adams' generic name in a sec- tional sense. The organization throughout is otherwise very similar to that of Plaxiphora. Two species only are known : P. egrcgia, in which the shell is of a peculiar cg.ir shape, wider behind the middle, and the insertion plates are much thickened outside at the edges of the slits, and P. ovata, in which the shell is widest at the fourth valve, rapidly narrowing toward both ends.
The following description of his new genus is given by H. Adams :
i. \ \ i
/ • , jni. nov. Testa ovali-, convexa. Valv:i- tran.-\-
cariiiata1; apex p..Mrrioris valva- terminal!-, produeta, : Limlms anirii>tiis, posticr H-sii-. srti- conn-is den-e ol».-itu-. The covering of the mantle, the form of the visible portions of the valves, and the peculiarity ot'tlie terminal valve, render thi- ftpecfol distinct from any form of Chitonidrc yet descril.ed. It lias the appearance ofa7,"nm with the mantle covered with long bristles instead of imbricate scales."
There seems to be no reasonable objection to the correction of the etymology of Frembly's name, which in H. Adams' article was incorrectly spelled through inadvertence or typographical error.
P. EGREGIA H. Adams. PI. 65, figs. 80, 81, 82.
Shell ovate, a little narrower in front, green-brown, paler at the sides. Anterior valve radially ribbed, the ribs pustulose, interstices obliquely lirate ; posterior valve and median valves subcarinate, the dorsal areas densely longitudinally lirate; lateral areas radially rib- bed, the ribs pustulose. Girdle moderate, furnished with short, corneous spicules. (H. Ad.)
Length 15, breadth 9 mill.
"Habitat unknown" (Ad.); Newcastle, Australia (Dieffenbach, teste Cpr.)
Frembleya egregia H. AD., P. Z. S. 1866, p. 445, t. 38, f. 9.— Streptochiton tortuosus CPR., MS., olim.
Of this species I have seen a single mutilated specimen, no. 36,638 of the Smithsonian Institution register. It is yellowish along the middle and at the side margins of the valves, pale green on the side- slopes. The species differs from P. ovata in being widest behind the middle. Carpenter describes the type as follows : Shell olivaceous, maculated with more or less intense ; ovate, broad, elevated ; dorsal ridge rather acute, much elevated, the side-slopes straight. Valves strongly beaked, each one eroded in front from the attrition of the next valve forward. The central areas have about 16 line on each side, about equalling the interspaces in width. Lateral areas elevated, bicostate, the ribs strongly granose, granules larger at the sutures, intermediate space obliquely costate or v-costate. Anterior valve having 10 radiating ribs, the interstices sculptured with v-shaped sulci, the v'-s meeting over the ribs and rendering them somewhat nodulous. Posterior valve with posterior elevated mucro and a single posterior rib on each side ; posterior area very narrow
332 PLAXIPHORA.
and smooth. The girdle has soft hairs, and a few larger, and there is some trace of pores. The posterior slit in the girdle mentioned by Adams seems to be an accidental tear ; H. Adams believes the same.
Length 15, breadth 10 mill.; divergence 133°.
P. OVATA Hutton. PI. 54, figs. 34-40.
Shell short-oval, very wide in the middle, rapidly narrowing toward the ends ; moderately elevated, the dorsal ridge carinated, side slopes slightly convex. Surface lusterless, sculptured in "herring-bone1" pattern. Color buff along the ridge, pale olive-green on the side- slopes, with a small curved dark spot or two on each valve.
Median valves broadly v-shaped, the apices of the valves elevated and acute. Lateral areas narrow, a little raised, the diagonal rib sculptured with a series of closely super-imposed v's, their apices directed toward the beak of the valve, one limb of each v direc- ted outward, curving, and forming the sculpture of the pleura, the other limb forming an oblique corrugation of the lateral area (fig. 40). Sutural margin of each lateral area obliquely, coarsely granose. Central areas having a nearly smooth band along the dorsal ridge, and numerous slightly curving and diverging riblets on each side. Anterior valve small, its width about that of one side- slope of the fourth valve, its apex elevated and slightly recurved ; surface having 8 strong ribs, besides those at the sutural margins, the anterior ribs strongest and wider apart; ribs nodose, intervals obliquely corrugated. Posterior valve (figs. 36-39) small, forming an extremely narrow crescent, strongly curved upward at the acute pos- terior mucro, the front (" central ") area narrow, concave ; viewed from behind (fig. 37) it presents the appearance of a wide inverted v.
Interior bluish-white. Sinus exceedingly broad, rounded, the sutural-plates widely separated. Insertion plates long, having the slit near the posterior edge of the plate. Anterior valve having 8, median valves 1 slit. Posterior valve (fig. 39) having a keel-like insertion-plate without slits on each side, and a broad sinus in the middle behind.
Girdle rather narrow, yellowish, bearing a pore-tuft of hyaline white bristles at each suture and a fringe of bristles at the edge.
Length 15, breadth 13 mill.; divergence 112°.
Cook Strait; Duwdhi, Xcw Zealand ; on seaweed.
Acanthochcetes ovatus HUTTON, Trans. N. /. lust, iv, p. 182 (1872).
ri. \\irii<
ovotui Hi PTCW, Man. N. X. M"1I., p. 177 -1880.) This species differs from / a in contour Bivalve
the widest, tin- .-ixth mueh n:irrnw.-r. whilst in t species the fifth and sixth valves are as wide as tin- fourth : i <»\-er the side teeth of ovafa do IK.I ieen to l)c thickened at the edges of the slits as they an- in f///vv//'./. The specimen described and figured was sent by Professor Iluttoii.
ERRATA.
Page 75, dele the word ISCHNOCHITON, in 8th line.
Page 97, 1. CURTISIANUS is not an Ischnochiton but a Liolophura,
see p. 242.
Page 110, For "7. regulatw" read " J. rugulatiu." Page 133, " I. PUSIO" is probably not an Ischnochiton, but a true
Chiton, and it is likely to prove identical with Chiton
murrayi Haddon, described on p. 161.
Page 151, line 11, for " indentification" read "identification." Page 182, last line, remove " C. scytoderma " from the synonymy
of C. rubicundus. Page 191. The authority for C. SULCATUS should be " Wood," not
" Sowerby."
Page 204, line 14, for "indentification" read "identification." Page 206, fifth line from bottom ; the reference to Savijrny should
read " t. 3, f. 6, 1-2," instead of" f. 4." Page 329. " Chiton (Acanthopleura') piceolus" Shuttlew., included
under Acanthopleura granulata as a doubtful synonym,
is probably referable to the genus NUTTALLINA, s. g.
Middendorffia, and it should be compared with JV.
rlnerea Poli, p. 283.
NOTE.
The Index to Chitons will accompany the conclusion of the mono- graph, to be contained in the next part of the MANUAL.
EXPLANATION OF PLATES.
NOTE. — The drawings credited to Foord, Smith and Emerton were prepared under the supervision of Dr. Carpenter, and were loaned by the Smithsonian Institution, for reproduction in the MANUAL.
PLATE 1.
FIGURE. PAGE.
1-13. Lepidopleurus benthus Haddon. Challenger, . . 9 14-22. Lepidopleurus belknapi Dall. Challenger, . . 7
PLATE 2.
23-31. Lepidopleurus alveolus Sars. Moll. Arct. Norv., 6
39, 40. Lepidopleurus pagenstecheri Pffr. Moll. S. Georg., 12
41, 43-46. Lepidopleurus cajetanus Poli. Ross del., . 15
42. Lepidopleurus cajetanus Poli. Conch. Icon., . . 15 47-50. Lepidopleurus grauoliratus Cpr. Pilsbry del., . 14 51-53. Lepidopleurus granoliratus Cpr. Foord del, . 14
PLATE 3.
54-57. Lepidopleurus cancellatus Sowb. Moll. Reg. Arct., . 3 58. Lepidopleurus cancellatus Sowb. Ross del., ... 3 59-63. Lepidopleurus arcticus Sars. Moll. Reg. Arct., . 5 64-66. Lepidopleurus asellus Speng. Ross del., . .13
67-70. Lepidopleurus rugatus Cpr. Pilsbry del., . . .11 71-79. Hanleya hanleyi Bean. Moll. Reg. Arct., . . 17
PLATE 4.
74-77. Hanleya hanleyi var. abyssorum Sars. Moll. Reg.
Arct 18
|78-81. Lepidopleurus curvatus Cpr. Emerton del., . .16 82-84, 85. Hanleya mendicaria M. & A. Emerton del., . 18 83. Hanleya mendicaria M. & A. Inv. Mass., . . .18
86. Lepidopleurus rarinotus Jeffr. P. Z. S., . See Appendix.
87. Lepidopleurus catillus Rv. Conch. Icon., . . .10
88. Lepidopleurus fuliginatus Ad. & Rv. Conch. Icon., . 10
PLATE 5.
89-100. Hemiarthrum setulosum Cpr. Challenger Rep., . 20
(334)
i \i-i \- - 335
1 :;. iromiarthnini srtulosuni Cpr. Moll. > ' . . 20
4-8. Qemiarthrom wtolotum Q>r, Kmrrton <!.•!.,
I'I.MI. •;.
9-11. Mirroplax «^rayi A«l. A' An-. K. A. Smith del., . 21
12-H). Ilanli'va ti-MpHMlis Dull. Km.Tton del., . . .19 17, IS. II:uilry:itr..picalis Dall. ' I5l:.k«- ' Moll., . . . !'.»
19, 21. Trachydrrmon sU-im-nii I'liV. Moll. S. (ieorg., . 22-24. Trachydermon lividus Mi<ld. Mai. Ross., . . 76
25-27. Trarhydennon cincreus L. Moll. Reg. Arct., .
28. Trachydermon cinereus L. Ross del., . . . , 6fl
29, 30. Trachyderinoii cinereus L. Pilsbry del., ... 68 31. Trachydermon cinereus L. Hist. Br. Moll., . . .68 32-34. Trachydermon allms L. (head and tail valves badly
drawn). Emerton del., 70
PLATE 7.
35. Trachydermon albus L. Moll. Reg. Arct., . . 70
36-38. Trachydermon albus L. Pilsbry del., . . 70
39-45. Trachydermon exaratus Sars. Moll. Reg. Arct, 71
46-49. Trachydermon exaratus Sars. Tr. Conn. Acad., 71
50-56. Trachydermon ruber L. Moll. Reg. Arct., . 80
57. Trachydermon cinereus L. Pilsbry del., . . 68
58. Trachydermon cinereus var. variegatus Phil. Moll. Sicil. 69 59-60. Trachydermon cinereus var. variegatus Phil. Moll
Rouss., 69
PLATE 8.
61-65. Trachydermon dentiens Gould. Pilsbry del., . . 73
66-68. Trachydermon scrobiculatus Midd. Mai. Ross., . 76
69, 70. Trachydermon pusillus Sowb. Conch. Icon., . . 80
71. Trachydermon stramineus Sowb. Conch. 111., . . 79
72, 73. Trachydermon virgatus Rv. Conch. Icon., . . 78 74, 75. Trachydermon virescens Rv. Conch. Icon., . . 7s 76, 77. Trachydermon puniceus Couth. Expl. Exped., , 81 78, 79. Chsetopleura cullierti Rochebr. Moll. Cap Horn,
[See Appendix
80, 82. Callochiton fulgetrum Reeve. Conch. Icon., . . 83
81. Cal loch i ton fulgetrum Reeve. Cpr. del., . . . .83 83-85. Callochiton lobatus Cpr. Emertou del., . . .53
PLATE 9.
86, 87, 91. Callochiton castaneus Wood. Conch. 111., . . 52
88, 89, 90. Callochiton castnneus Wood. Pilsbry del., . . 52
92. Callochiton illuminatiis Rve. Emerton del., . . .51
93, 94. Callochiton illumiuatus Rve. Conch. Icon., . . 51
336 I :\1 I .A NATION OF PLATES.
95, 96. Callochiton lievis Mont. Pilsbry del., ... 49 97, 98. Callochiton Irevis Mont. Hist. l*r. M..11, • 49
PLATE 10.
1, 2. Callocbiton platessa Gld. U. S. Exped., ... 49
3, 4, 5. Callochiton platessa Gld. Emerton del., . . 49
6. Callochiton versicolor Ad. (^platessa Gld.). P. Z. S., . 50
7. Callochiton crocinus Rve. (probably distinct from versi-
color). Conch. Icon., 50
8. 10-15. Tonicella marmorea Fabr. Moll. Reg. Arct, . 41 16-21. Tonicella submarmorea Midd. Emerton del., . .42 22-24. Tonicella subnmrmorea Midd. Mai. Ross., . . 42
PLATE 11.
25, 27. Tonicella lineata Wood. Ross del., . . . .42
26. Tonicella lineata Wood. Emerton del., . . . .42 28. Tonicella lineata Wood. Pilsbry del., . . . .42 29-31. Tonicella sitchensis Midd. Mai. Ross., ... 44 32-34. Schizoplax brandti Midd. Sib. Reise, ... 47 35-37. Schizoplax brandti Midd. Emerton del., . . .47 38, 39. Leptoplax coarctatus Sowb. Emerton del., . . 25 40, 41. Ischnochiton interstinctus Gld. U. S. Ex. Exped., . 119
PLATE 12.
42. Chsetopleura peruviana Lm. Ross del., . . . .28
43-46. Chsetopleura peruviana Lm. Emerton del., . . 28
47. Chsetopleura hennahi Gray. Conch. Icon., . . .29
48, 49. Chsetopleura hennahi Gray. Ross del., . . .29
50. Chsetopleura parallela Cpr. Ross del., . . . .34
51. Chaetopleura columbiensis Sowb. Conch. Illust., . . 34
52. Chsetopleura columbiensis Sowb. Conch. Icon., . . 34
53. 54. Chaetopleura lurida Sowb. Conch. Icon., . . 33 55, 56. Chsetopleura scabriculus Sowb. (=lurida). Conch.
Ill, . ... . 33, 34
PLATE 13.
57, 58. Chsetopleura isabellei Orb. Voy. Ame"r. Me>id, . 35
59. Chsetopleura janeirensis Gray. Conch. 111., . . .37
60. Chsetopleura janeirensia Gray. Pilsbry del., . . .37 61,62. Chiton segmentatus Rv. Conch. Icon.(=Chsetopleura
janeirensis), ... .... 37
63, 64. Chsetopleura spinulosa Gray. Conch. Icon., . . 38 65, 66. Chsetopleura dieffenbachi Rve. Conch. Icon., 67, 68. Chsetopleura sowerbyana Rve. Conch. Icon, . . 39 69, 70. Chsetopleura gemmea Cpr. Emerton del., . . 31 71-74. Chsetopleura gemmea Cpr. Ross del., . . .31
i \ri.\\ \ i [OX Of i'i \
PLATE i i.
80. Chaetopleura Dobilis Rve. ( ouch. Icon.,
81. Cyanoplax hart uviri < '|>r. Original, . . . .45 82,83. Cyanoplax hart wriri < '|>r. Kiin-rton del., . . . 1-0 84,85. Cyanoplax bartwegi Cpr. Ross del., . . . l."» 86-81*. Ischii.,rliit«.n acrior Cpr. Ross del., . . . «:i
90, Cyanoplax hipunrtatus Sowb. Conch. 111., . . .46
PLATE 15.
91, 93. Ischnochiton conspicuus Cpr. Ross del., . . . J63
92, 96. Ischnochiton conspicnus Cpr. Piisbry del., . . 63 94, 95. Ischnochiton conspicuus Cpr. Emerton del., . . 63
97. Ischnochiton conspicuus var. solidus Cpr. Emerton del., 64
98, 100. Ischnochiton magdalenensis Hds. Ross del., . . 62
PLATE 16.
1, 2. Ischnochiton alatus Sowb. Emerton del., . . .60 3, 4. Ischnochiton alatus Sowb. Piisbry del., . . .60 5. Ischnochiton alatus Sowb. Ross del., . . .60
6-8. Ischnochiton juloides Ad. P. Z. S., .... 55 9, 10. Ischnochiton limaciformis Sowb. Ross del., . . 57
11, 12. Chiton productus Rv. (=1. limaciformis). Conch.
Icon 57
13, 14. Chiton sanguineus Rv. (=1. limaciformis). Conch.
Icon., 57
15, 16. Ischnochiton limaciformis Sow. Conch. Icon., . . 57
17, 18. Ischnochiton fallax Cpr. Emerton del., . . .59
PLATE 17.
19, 20. Ischnochiton floridanus Pils. Ross del., . . .58
21, 22. Ischnochiton floridanus Pils. Piisbry del., . . 58
23, 23. Ischnochiton purpurascens Ad. Ross del., . . 58
24. Ischnochiton purpurascens Ad. Emerton del., . . 58 25 26. Ischnochiton pectinatus Sowb. Ross del., . . .64 27, 28. Ischnochiton pectinatus Sowb. Emerton del., . . 64
29. Ischnochiton pectinatus Sowb. Piisbry del., . . .64
30. Chiton acutiliratus Rv. (— I. pectinatus Sowb.). Conch.
Icon., . 64, 65
32, 33. Ischnochiton viridulus Couth. U. S. Exped., . . 141
39. Chsetopleura hennahi Gray. Piisbry del., . . . 29
PLATE 18.
35-39. Ischnochiton tridentatus Piisbry. Piisbry del., . 140
40. Ischnochiton trifidus Cpr. Cpr. del. (see appendix), . 141 41-46. Ischnochiton regulari^ Cpr. Emerton del., . .142
22
338 EXPLANATION OF PLATES.
47,48. Ischnochiton dispar Sowb. Conch. Icon., . . .111
4'.), 50. Ischnochiton inquinatiu Rve. Conch. Icon., . . 90
51-55. Ischuochiton adamsii Cpr. Pilsbry del., . . .111
56, 57, 59. Ischnochiton australis Sow. Pilsbry del., . .144 58. Ischnochiton australis Sow. Conch. Icon., . . .144
PLATE 19.
60, 61. Ischnochiton tigrinus Krauss. Siidafrik. Moll., . 143 62, 63. Ischnochiton tigrinus var. unicolor Pils. Pilsbry
del., . . 143, 144
64-66. Ischnochiton hakodadensis Cpr. Pilsbry del., . 147
67. Ischnochiton novoehollandiit Gray. Pilsbry del., . . 145
68. Ischnochiton noviehollandite Gray. Ross del., . . 145
69. Ischuochitou novBedollandirc Gray. Conch. Icon., . . 145 70-74. Ischnochiton albrechti Schrenck. Amurl. Moll., . 147
PLATE 20.
1-4. Ischnochiton rissoi Payr. Bull. S. Mai. ItaL, . .102 5-7. Ischnochiton rissoi Payr. (young). Bull. S. Mai. Ital., 102
8-10. Ischnochiton rissoi var. meneghinii. Journ. Conch., . 103
11. Ischnochiton yerburyi Smith. P. Z. S., . . . . 101
12, 3, 14, 15. Ischnochiton oniscus Kr. Siidaf. Moll, . 100 16, 17. Ischnochiton reticulatus Rv. Conch. Icon., . . 101 18, 19. Ischnochiton pertusus Rv. Conch. Icon., . . . 103 20. Ischnochiton striolatus Gray. Conch. Icon., . . . 105 21-24. Ischnochiton striolatus Gray. Ross del., . . . 105 25, 26. Ischnochiton caribreorum (Cpr.) Smith (=1. striola- tus). J. Linn. Soc., 107
PLATE 21.
27, 28. Ischnochiton pruinosus Gld. U. S. Expl. Exped., . 109
29-34. Ischnochiton imitator Smith. P. Z. S., 116
35, 38. Ischnochiton punctulatissimus Sowb. Conch. 111., . 115
36, 37. Ischnochiton punctulatissimus Sowb. Pilsbry del., .115
39. Ischnochiton interstinctus Gld. Pilsbry del., . .119
40, 41. Ischnochiton papillosus Ad. Ross del., ... . 114 42-46. Callistochiton shuttleworthianus Pils. Pilsbry del., . 273 47, 48. Ischnochiton catenulatus Sowb. Conch. Illust., . 110
49. Ischnochiton roseus Sowb. Conch. Icon., . . .113
50. Ischnochiton roseus Sowb. Conch. Illustr., . . .113
51. 52. Ischuochiton colubrifer Rve. Conch. Icon., . . 95 •r> •'). Ischnochiton rugulatus Sowb. Beechey's Voy., . .110 54-56. Ischnochiton rugulatus Sowb. Couch 111., . .110
57. Ischnochiton rugulatus Sowb. Conch. Icon., . . .110
i. \I-I\N \ i [OH OF PLJ
I'I.M i: 22.
58, [sohnochiton loDgioymba Q. db Q, K'"- del., . . 87
[•chnochiton loDgicymba Q. <& G. A-tn.l.. . . .87
<;o-i;»;. Isrimorhit.m longicjmbfl o. A GK I'iUi.rv del., . 87
Kshnoohiton huddoni I'ik I'ilsb.-y del., . 88 68,70,71. C. longicrmba Sow. ( I. haddoni I'ik;. Conch. 111.. . . ...
69. C. loiiLrirymhu live. (=1. haddoni I'ils.). Conch. Icon., .
74. Ischnochiton divi-ri^'ns Rve. Pilsbry del., . . .90 75,76. Ischnochiton divergens Rve. Ross del.,
77. Ischnochiton divergens Rve. Conch. Icon., . . .90
PLATE 23.
78. 80. Ischnochiton fruticosus Old. U. S. Ex. Exped., . 91
79. Ischnochiton fruticosus Gld. Pilsbry del., . . .91 81, 82. Ischnochiton contractus Rve. Conch. Icon., . . 93 83, 84. Ischnochiton decussatus Rve. (=contractus). Conch.
Icon.. ......... 93, 94
85. Ischnochiton exiguus Sowb. Conch. Illustr., . . .98
86. Ischnochiton exiguus Sowb. Conch. Icon., . . .98
87. 88. Ischnochiton castus (—contractus). Conch. Icon., 93, 94 89, 90. Ischnochiton sculptus Sowb. Conch. Illustr. . . 92 91. Ischnochiton pallidus Rve. Conch. Icon., . . .89 92,93. Ischnochiton petaloides Gld. U. S. Exped., . .118 94, 95. Ischnochiton carinulatus Rv. Conch. Icon., . . 96 96, 97. Ischnochitou pallidulus Rv. Couch. Icon., . . 95
PLATE 24.
98, 99. Ischnochiton crispus Rve. Conch. Icon., . . .89
100, 1-4. Ischnochiton ustulatus Rve. Emerton del., . . 96
o. Chiton granulosus Frembly. Zool. Journ., . Appendix.
6. Liolophura curtisiana Smith. ' Alert ' Zool., . . . '24-
7, 8. Ischnochiton adelaidensis Rve. Conch. Icon., . .136 9, 10. Ischnochiton muscarius Rve. Conch. Icon., . .132
11, 12. Ischnochiton ustulatus Rve. Conch. Icon., . . 96 13-15. Ischnochiton tessellatus Q. & G. Astrol.,
16, 17. Ischnochiton arbutum Rve. Conch. Icon., . .139
18, 19. Ischnochiton milleri Gray. Conch. Icon., . . . 137 20-22. Ischnochiton cariosus Cpr. var. subcariosus Pils.
Pilsbry del., ....... 65, 67
23. Ischnochiton cariosus Cpr. typical. Emertou del., . . 65
PLATE 25.
1-10. Ischnochiton dalli Haddon. Chall. Rep ..... 133
11-19. Ischnochiton dorsuosus Haddon. Chall. Rep., . . 135
340 i:\l-LANATION OF PLATES.
PLATE 26.
20, 21. Ischnochiton mertensii Midd. Ross del., . . . 125
22, 24-26. Ischnochiton mertensii Midd. Pilsbry del., . 125
23. Ischnochiton mertensii Midd. Emerton, . . .125 27. Ischnochitou cooperi Cpr. Ross del., . . . .127 28-30. Ischnochiton cooperi Cpr. Pilsbry del., . . . 127 31-33. Ischnochiton clathratus Rve. Pilsbry del, . . 128 34. Ischnochiton clathratus Rve. Emerton del., . . . 128
PLATE 27.
35-39. Ischnochiton lindholmi Schr. Amurl. Moll., . . 85 40-43. Ischnochiton cyaneopunctatus Kr. (=lentiginosus
Sowb.) 8uda£Moll., 135
44. Ischnochiton lentiginosus Sowb. Conch. 111., . . . 135
45, 46. Ischuochiton versicolor Sowb. Conch. Illustr., Appendix. 47, 48. Ischnochiton pulcherrimus Sowb. Conch. Icon., . 130
49. Ischnochiton constant! Velain. Arch. Z. Expe>., Appendix.
50. Ischnochiton coreanicus A. & R. Conch. Icon., . .129
51. Ischnochiton bergoti Velain. Arch. Z. Expe*r., Appendix. 52-54. Ischnochiton inca Orb. Voy. Amer. M£rid., Appendix.
PLATE 28.
1-4. Chiton sulcatus Wood. Ross, del., . . . .191 5-8. Chiton goodalli Brod. Ross, del., . . . .191
PLATE 29.
9. Chiton goodalli Brod. Conch. Icon., .... 191 10. Chiton barnesi Sowb. Conch Icon., .... 190 11,12. Chiton barnesi Sowb. Pilsbry del., , . .190
13, 14. Chiton (?) dimorphus Rochebr. Miss. Cap Horn.
(See appendix). 15-21. Chiton murrayi Haddon (?— C. pusio Sowb., p. 133).
Chall. Rep., . .161
PLATE 30.
23. Chiton magnificus Desh. Ross del., . . . .160
24. Chiton magnificus Desh. Emerton del., . . . .160
25. Chiton stokesii Desh. Conch. Icon., .... 165 2(>. Chiton stokesii Desh. Original, 165
27. Chiton granosus Frenab. Pilsbry del., . . . .167
28. Chiton granosus Fremb. Zool. Journ., .... 167
29. 31. Chiton cumingi Fremb. Conch. Icon., . . .164
30. Chiton cumingi Fremb. Ross del., .... 164
i MM. \N \ i IMS .,i i-i • :;il
PLATE 81,
!. Chiton PUftidU D.'-h. Moll. K.'iiri., . . 186 8, ( 'liiton lyratns Sowb. C-.nch. Iron 184
37, 38. Chiton anguttiooftatai Q. v -1 187
:;•.», in. Chiton mftorititnafl Voy, Voy. Astro].. . . 188
II, I'J. Chiton oaptMisis Gray (— nigroviivns I>lv.). Conch. Icon., ...... .
43. Chiton cymbiola So\\l>. ( tulipa (,).). Conch. Icon.,
44, 46, 47. Chiton tulip* Quoy. KOSH del., . . . .185
46. Chiton tulipa Quov. Voy. Astrol. 185
48, 49. Chiton cymbiola Sowb. (^tulipa Q.) ... 185
PLATE 32.
50. Chiton patulus Brod. (—stokesii Brod.). Conch. Icon., !•;."> 51-52. Chiton stokesii Brod. Pilsbry del., . . . . I'M
53. Chiton stokesii Brod. (1 sq. mm. of girdle indicated),
I'.lsbrydel., 165
54. Chiton virgulatus Sowb. Conch. Icon., .... IHO
55. 56. Chiton virgulatus Sowb. Pilsbry del., . . . 166
57. Chiton albolineatus Sowb. Conch. Illustr., . . . 160
PLATE 33.
58, 59, 60. Chiton tuberculatus L. Ross del., . . .153
61. Chiton tuberculatus var. assimilis Rv. Conch. Icon., . !">">
62. Chiton tuberculatus var. assimilis Rv. Ross del., . . 155
63. Chiton tuberculatus var. assimilis form ater. Ross del., 155
64. Chiton foveolatus Sowb.) (•— viridis Spengl.). Conch.
Icon., . . . 156
65. Chiton viridis Spengl. Ross del., !•">»>
66 67. Chiton viridis Spengl. Pilsbry del., .... 156
PLATE 34.
68. Chiton lievigatus var. arfciculatus Sowb., ventral view.
Emerton del., 1">9
69. Chiton laevigatus var. articulatus Sowb. Conch. Icon., . 159
70. Chiton Isevigatus var. articulatus Sowb. interior. Pilsbry
del., . . . . . . . . . 169
71. Chiton Isevigatus Sowb., typical. Conch. Icon., . . 159
72. 74. Chiton marmoratus Gmel. Ross del., . . .158
73. Chiton marmoratus Gmel. Conch. Illustr., . . . l.~>s
75. Chiton marmoratus Gmel., interior. Pilsbry del., . . 1">*
76. Chiton marmoratus Gmel. Conch. Icon., . . . 158 77-79. Chiton canariensis Orb. Moll. Canar., . . .184
PLATE 35.
80. Chiton marmoreus Rv. (=squamosus L.). Conch. Icon., 155
81. Chiton s«iuamosus L., one-half valve. Pilsbry del., . !">">
342 i:\ri.\NATIONOFPLATE8.
82. Chiton squaruosus L. Ross del., 155
83,84. Chiton insularis Rochebr. Nouv. Arch., . . . 183 85, 86. Chiton hamyi Hochebr. Nouv. Arch., . . .183 87, 88, 90. Chiton o'livaceus Speng. Pilsbry del., . . 180 89, 91,92. Chiton olivaceus Speng. Ross del., . . .180 93. Chiton affinis Issel. Savigny, 181
PLATE 36.
91. Chiton jugosus Gould. U. S. Exped., . . . .178
92. 94, 95. Chiton jugosus Gould. Pilsbry del., . . . 17K
93. Chiton jugosus Gould. Ross del., 178
96, 97. Chiton jereus Rve. Conch. Icon., . . . .179 98, 99. Chiton marquesanus Pils. Pilsbry del., . . . 170
100. Chiton marquesanus Pils. Ross del., . . . .170
1. Chiton sinclairi Gray. Erebus & Terror, . . . 174
2, 3. Chiton sinclairi Gray. Pilsbry del., . . . .174 4,6. Chiton canaliculatus Q. Pilsbry del., . . .177
5. Chiton insculptus Ad. (—canaliculatus Q.). P. Z. S., . 177
PLATE 37.
6. Chiton quoyi Desh. (color var.). Ross del., . . .172
7. Chiton quoyi Desh. (sculpture) Pilsbry del., . . . 172
8. Chiton quoyi Desh. Conch. Icon., . * . . . . 172
9. 10. Chiton caliginosus Rve. Conch. Icon., . Appendix.
11. Chiton dissimilis Rve. Conch. Icon., .... 184
12, 13. Chiton muricatus Ad. P. Z. S., . . . .175 14, 15. Chiton pellisserpentis Q. Ross del., . . .173
16. Chiton pellisserpentis Q. Astrol., . . . .173
17. Chiton pellisserpentis Q. (1 sq. mill, of the girdle indicated).
Pilsbry del 173
18. Chiton pellisserpentis Q. Emertou del., . .173
PLATE 38.
19. Chiton subfuscus Sowb. typical. Conch. Icon., . 162, 163
20. Chiton subfuscus var. mesoglyptus Pils. Conch. 111., . 164
22. Chiton subfuscus var. mesoglyptus Pils. Ross del., . 164
21. Chiton subfuscus var. mesoglyptus, valve of same specimen
as fig. 22. Pilsbry del. 164
23. Chiton bowenii King. Conch. Illustr., . . . .164 •J4-26. Ischnochiton sulcatus Q. & G. Voy. Astrol., . . 138 27, 28. Chiton tenuistriatu* Sowb. Conch. 111., . . . 188 29, 30. Chiton cingillatus Rve. Conch. Icon., . Appendix. 31, 32. Chiton luzonicus Rve. Conch. Icon., . Appendix. 33,34. Chiton aquatilis live. Conch. Icon., . 169
PLATE 39. 35. Tonicia disjunct:! Fremb. Conch. Icon.. . . . 212
\ N \ TIMS 01 PI LTBB.
36—11. Tonicia disjunct* I-'n-mh. Kmcrton <ld., .
42— '1. < 'r:i-|irdi'diili>n l:i<| uc;it u> Sli ul (. Kinrrtoii del.,
52. [iohnooniton ragulatui Sowb var, Condi. Iron., . . no
PLATE 40.
1,2. Tonieia truncate Sowb. Condi. Icon., . . . LMI
.3,4. Tonioia fortilirate Sowb. Condi. Icon., . . . _<>7
5,6. Tonirin j»ii'ta So\vh. Conch. Icon., . . . .211
7. Tonicia carpenteri Angas. P. Z. S., .... iio.s
8-11. Tonicia lamellosa Q. & G. Voy. Astrol., . . ,209
12. Tonicia /sdumi I'flr. Moll. S. Georg., . . . ,204
13-15. Tonieia tehuelchus Orb. Voy. Ame>. Me*rid., . . 205
16, 17. Tonieia suezensis Rve. Conch. Icon., . . . 206
PLATE 41.
19. Tonieia chilensis Fremb. Pilsbry del., . . . . l'.»7
20. Tonieia chilensis Fremb. Conch. Icon., . . . .197
21. Tonicia fastigiata Sowb. Pilsbry del, . . . .199
22. Tonieia elegans Fremb. Pilsbry del., . . . .196 Betw. 22 and 24. Touicia elegans Fremb. (color-pattern only).
Pilsbry del., ........ . ]S6
24. Tonieia elegans Fremb. (second valve). Pilsbry del., . 196
25. Tonieia lineolata Fremb. Conch. Icon., . . . .198
26. Tonieia lineolata Fremb. Zool. Journ., .... 198
27. Tonieia lineolata (var. connecting with elegans). Ross
del., .......... 198
28. Tonieia atrata Sowb. Conch. 111., . . . .201
29. 30. Tonieia atrata Sowb. Conch., Icon., . . .201
PLATE 42.
31. Tonieia elegans Fremb. Ross del., . . . .196
32. Tonieia elegans Fremb. var. Conch. Icon., . . .196
33. 34, 35. Tonieia elegans Fremb. (not typical). Emerton,
del., ....... . . .196
36-39. Tonieia fastigiata Gray. Conch. Icon, . . .199
40. Tonieia chilcensis (=fastigiata). Conch. Icon., . .199
PLATE 43.
41. Tonieia swainsoni Sowb. Conch. Icon., .... 201
42. Tonieia swainsoni Sowb. Pilsbry del., .... 201 4.'>. Tonieia swainsoni Sowb. Ross del., .... 201 44, 45. Tonieia granifera Sowb. Conch. Icon., . . . 200 46, 47. Tonieia grayi Sowb. Conch. Icon., .... 200 48, 49. Tonieia (?) martieli Rochebr. Moll. Cap Horn, . 203 50, 51. Tonieia horniana Rochebr. Moll. Cap Horn, . . 203 52, 53. Tonieia lebruni Rochebr. Moll. Cap. Horn, . . 203
344
EXPLANATION OF PLATES.
54,55. Tonicia sch ram mi Shuttle w. Pilsbry del., . . 205
56, Tonicia schrammi Shuttlew. Journ de Conch., . . 205
PLATE 44.
57, 60. Chaetopleura watsoni Sowb. Conch. Icon., See appendix.
58, 59. Chsetopleura watsoni Sowb. Conch. 111., See appendix.
61. Chaetopleura castanea Q. Voy. Astrol., . See appendix.
62. Chaetopleura fulva Wood. Ross, del., . . See appendix.
63. Chsetopleura fulva Wood. Conch. Icon., . See appendix.
64. Chaetopleura fulva Wood. Pilsbry del., . . See appendix.
65. 67. Tonicia rubridens Pils. Pilsbry del., . . .202
66. Tonicia rubridens Pils. Ross del., 202
68. Craspedochiton laqueatus Sowb. Conch. Icon., . . 285
PLATE 45.
69, 70. Tonicia crenulata Sowb. Conch. Icon., . . 195 71, 72. Tonicia crenulata Sowb. Ross del., . . . 195
73. Chiton rubicundus Costa. Catal., .... 182
74, 75. Chiton pulchellus Phil. (=rubicundus Costa). Enum. 182 76, 77. Acanthopleura borbonica Dh. Pilsbry del., . 230 78, 79. Acanthopleura borbonica Dh. Moll. Reun., . 230 80, 81, 83, 84. Acanthopleura spinosa Brug. (valves i, ii, viii)
Emerton del., 220
82, 87. Acanthopleura spinosa Brug. (valve iv). Pilsbry del., 220
85. Acanthopleura spinosa Brug. Conch. Icon., . . . 220
86. Acanthopleura spiuosa Brug. (girdle spines). Emerton
del., .... 220
PLATE 46.
88. Eudoxochiton nobilis Gray (type). Erebus & Terror, . 193
89, 90. Eudoxochiton nobilis Gray (valve vii). Pilsbry del., 193 91. Eudoxochiton nobilis Gray (interior). Emprton del., . 193 92-94. Eudoxochiton nobilis Gray (valve viii). Pilsbry del., 193
95. Eudoxochiton nobilis Gray. Pilsbry del., ; . .193
96, 100. Eudoxochiton huttoni Pils. (valve vii). Pilsbry del., 194
97. Eudoxochiton huttoni Pils. Ross del., .... 194
98, 99. Eudoxochiton huttoni Pils. (valve viii). Pilsbry del., 194 1-5. Chiton miles Cpr. Emerton del., . . . 188
PLATE 47.
6-9, 11-14. Acanthopleura echinatum Barnes. Emerton
del., 218
10. Acanthopleura echinatum Barnes. Zool. Journ., . . 218 15-17. Acanthopleura echinatum (young). Emerton del., . 218 18-20. Acanthopleura brevi>pin<»>:i ><i\vli. Kmerton del., . 231 21. Acanthopleura brevispinosa Sowb. Ro&s del., . . 231
EXPLANATION OF FLA1
PLATE 48.
22. Acanthoplruni spinier Sowl). Charlc.sworth's Mag. Nat.
Hist., . . . . . . 221
23. Aoanthopleara ipiniger Sowb. Conch. Illustr., . . L'LM •J I •_''',. AcaiitIi(>|)l(Mira spiniger Sowb. (Interior, and posterior
valv,-). 1'ilsbry del., . .221
27. Acanthoploiira spiniger Sowb. Conch. Icon., . .221
28. Acanthopleura spiniger var. granata Rv. Pilsbry del., 224,
[225
29. 30. Acanthopleura spiniger var. granata Rv. Conch.
Icon., . . . . . . . . . 224, 225
31. Acanthopleura spiniger var. (Viti Is.) Ross del., . . 223
32. Acanthopleura spiniger var. (Viti Is.). Pilsbry del., . 223
PLATE 49.
33,34. Acaiithopleura spiniger var. cunninghami Rve. Conch.
Icon 225
35, 36. Chiton linter (Chemn.) Rve. Conch. Icon., (See
appendix.) 37, 38. Chiton piceus Rv. not Linn. (=A. spiniger var. obesa
Shuttl.) . .226
PLATE 50.
39. Acanthopleura granulata Gmel. (St. Thomas). Ross del., 227
40, 41. Acanthopleura granulata Gmel. (group of white and
of dark spines). Pilsbry del., 227
42. Acanthopleura granulata Gmel. (occidentalis Reeve).
Conch. Icon., 227
43. Acanthopleura granulata (Key Vaccas, Fla.). Ross del., 227 44-47. Acanthopleura granulata Gmel. (St. Domingo).
Pilsbry del., 227
48. Acanthopleura granulata Gmel. (St. Thomas). Ross del., 227
49. Acanthopleura granulata Gmel. Emerton del., . . 227
PLATE 51.
1. Schizochiton incisus Sowb. 235
2. Schizochiton incisus Sowb. (half of head valve). O. J.
M. S., . 235
3. Schizochiton incisus Sowb. (eye, x 200). Q, J. M. S., . 235 4-5. Schizochiton incisus Sowb. (valves i and ii). Emerton
del., 235
6-8. Schizochiton incisus Sowb. (valve viii, ventral, profile
and posterior views). Emerton del., .... 235 9-12. Lorica angasi Ad. & Ang. Emerton del., . . . 238
346 I : X I -LANATION OF PLATES.
PLATE 52.
14. Lorica cimolea Rv. (=volvox Rve.). Conch. Icon., . 237
15. Lorica volvox Rve. Ross del., 237
16. Lorica volvox Rv. (1 sq. mill, of girdle). Pilsbry del., . 237
17. 18. Lorica volvox Rv. (posterior valve). Pilsbry del., . 237
19, Lorica volvox Rv. (anterior valve). Pilsbry del., . . 237
20, 21. Lorica volvox Rv. (intermediate valve). Pilsbry del., 237 22, 23. Enoplochiton niger Barnes (posterior valve). Emer-
ton del., 252
24, 25. Enoplochiton niger Barnes (intermediate valve).
Pilsbry del., . . . . .252
26. Enoplochiton niger Barnes. Ross del., .... 252
27. Enoplochiton niger (surface). Q. J. M. 6., . . . 252
28. Enoplochiton niger (surface). Q. J. M. S., . . 252
29. Enoplochiton niger (girdle of a young specimen). Emer-
ton del., 252
PLATE 53.
30. Liolophura iucanaGld.(=L. gaimardi Blv.). U. S. Expl.
Exped., 240
31. Liolophura gaimardi Blv. (girdle spines). Pilsbry del., . 240
32. Liolophura gaimardi Blv. Ross del., .... 240 33-35. Liolophura gaimardi Blv. Pilsbry del., . . .240 36-40. Liolophura georgiana Q. & G. Voy. Astrol., . . 241
41. Liolophura japonica Lisch. (Girdle spines). Pilsbry del., 242
42. Liolophura japonica Lisch. Ross del., .... 242
43. 44. Liolophura japonica Lisch. Jap. Meeres-Conch., .242
45. Liolophura japonica var. tessellata Pils. Ross del.,
46. Liolophura japonica var. tessellata Pils. Pilsbry del., . 243
PLATE 54.
21, 22. Nuttallina scabra Rv. Pilsbry del., . . . .280 •2 :;, 24. Nuttallina californica Nutt. Pilsbry del., . . 279 25-27. Nuttallina alternataSowb. Conch. 111., . . .281 28-30. Nuttallina cinerea Poli. Emerton del., . . . 283
31. Nuttallina cinerea Poli (edge of girdle x 100). Pilsbry
del., 283
32. Nuttallina cinerea Poli. Test. Utr. Sic., . . . .283
33. Nuttallina cinerea Poli (girdle x 50 ca.) Pilsbry del., . 283
34. 35. Plaxiphora ovata Hutt. Pilsbry del., . ' . .332 36-39. Plaxiphora ovata Hutt. (profile, posterior, dorsal and
ventral views of posterior valve). Pilsbry del., . . 332 40. Plaxiphora ovata Hutt. (sculpture of intermediate valves).
I'ilsbrydel., 332
41-45. O. caliginosus Cpr. (=Liolophura japonica Lisch.)
Emerton del., . 244
46. Onithochiton amicorum Bd. Voy. Curacoa, . . .249
i \I-I.\N M i«. N MI- PLJ
*
l'l.\ I !
1. Onjthocbiton lyellii 8owb. ('..ndi. IIIu*tr 247
2. Onitbocbiton lyelli) Sowb. Condi. Icon., . . . LM? 3-7. Onitbocbiton lyellii 8owb, Bmerton del., . . .247
8,9. Onithodiiton iiidi IIv. ( lydlii S.»w!).). Conch. Icon., 248 10, 11. Onithudiitoii srmisnrlptus Pils. Koss del., . ,247 12, 13. Onithudiitoii <|iirrdmis(;l<l. I'. S. Kxped., 14, 1."). ( )nitlmdiit<m undulatus Q. & G. Roes del, . .245 L6. Onitbocbhon undulatas Q. ft G. Voy. Astrol., . .240 17, 18. Plaxiphora wahlbergi Kr. sndaf. Moll., . . .322
19. Onithoehiton ragulotns Anff. P. Z. S., . . . .249
20. Onithoehiton maillardi Desh. Moll. Reun., . . . 250 21-23. Onithoehiton literatus Kr. Sudafrik. Moll., . . 251
PLATE 56.
1, 4, 6. Pallochiton lanuginosus Cpr. Ross del., . . 257
2, 3. Pallochiton lanuginosus Cpr. Pilsbry del., . . 257 5, 7-11. Pallochiton lunuginosus Cpr. Emerton del., . . 2~>7
12-16. Nuttallina californica Nutt. Emerton del., . . 279 17, 18. Nuttallina californica Nutt. Ross del., . . .279 19, 20. Nuttallina scabra Rve. Ross del., . . . .280
PLATE 57.
21. Dinoplax gigas Gmel. Conch. Icon., .... 255
22. 27-31. Dinoplax gigas Gmel. Emerton del., . . . 255 23-26. Dinoplax gigas Gmel. (young). Siidafrik. Moll., . 255
32. Dinoplax gigas Gmel. (young). Ross del., . . . 255
33. 35. Tonicia confossa Gld. Pilsbry del., . . . .210
34. Tonicia confossa Gld. U. S. Expl. Exped., . . .210
PLATE 58.
1, 2. Callistochiton crassicostatus Pils. Emerton del., . . 264 3-6. Callistochiton crassicostatus Pils. Pilsbry del., . . 264 Fig. below 1, and 7, 8. Callistochiton palmulatus Cpr. Emerton
del., . . . . . . . . . .262
9-11. Callistochiton palmulatus var. mirabilis Pils. Pilsbry
del., 263
12. Callistochiton palmulatus (typical). Pilsbry del., . . 262 13-16. Callistochiton palmulatus (typical). Emerton del., . 262 17. Callistochiton decoratus Cpr. Ross del., . . . 269
18-20. Callistochiton decoratus Cpr. Pilsbry del., . . 269 21, 22. Plaxiphora ccelata Rve. Conch. Icon., . . .328
PLATE 59
21-26. Callistochiton pulchrior Cpr. (=pulchellus Gray).
Foord del., . . 272
348 EXPLANATION OF PLATES.
27, 28. Callistochiton elenensis Sowb. Conch. 111., . . 267
29, 34. Callistochiton antiquus Rv. Pilsbry del, . . . 274
30-32. Callistochiton antiquus Rv. Emerton del., . . 274
35. Callistochiton antiquus Rv. Conch. Icon., . . . 274
36. Callistochiton coppingeri Sm. ' A'lert ' Zool., . . . 275 •".7-42. Callistochiton infortunatus Pils. Foord, del., . . 266 43, 44. Callistochiton bicostatus Orb. (=pulchellus Gray).
V,,y. Am. Mrr., 272
45. Callistochiton adenensis Smith. P. Z. S., . . .278
PLATE 60.
1. Callistochiton pulchellus Gray. Spicil. Zool., . . . 271
2. Callistochiton pulchellus Gray. Conch. Icon., . . 271 3-6. Callistochiton pulchellus Gray. Pilsbry del., . .271
7-10. Callistochiton gabbi Pils. Pilsbry del., . . ,270
11-15. Callistochiton (?) heterodon Pils., . . ... 276
16. Callistochiton (?) heterodon var. savignyi Pils. Savig.
^Egypt, . 277
PLATE 61.
17-22. Callistoplax retusus Sowb. Emerton del., . . 288
23, 24. Callistoplax retusus Sowb. Emerton del., . . . 288
25. Callistoplax retusus Sowb. Conch. Illustr., . . . 288
26. Callistoplax retusus Sowb. Conch. Icon., . . . 288 27-32. Angasia tetrica Cpr. Emerton del., .... 287
33. Ceratozona rugosa Sowb. Conch. 111., .... 290
34. Ceratozona rugosa Sowb. (Santa Cruz). Pilsbry del., . 290
35. Ceratozona rugosa Sowb. Pilsbry del., . . . . 290
36. Ceratozona rugosa Sowb. (Jupiter Inlet). Pilsbry del, . 290
37. Ceratozona guildingii Rv. (r=rugosa Sowb.) Conch.
Icon., 290
38. 39. Ceratozoua setosa Sowb. Emerton del., . . .292 40. Ceratozona setosa Sowb. Conch. 111., . , ... 292 41-45. Ceratozoua rugosa Sowb. Emerton del., . . . 290
PLATE 62.
84, 85. Placiphorella stimpsoni Gld. (tail valve). Pilsbry del. 307
86. I'hiriphon-lhistimpsoiii Gld. (girdle- hair). Carpenter del. 307
87. Placiphorella stimpsoni Gld. Ross del., . . 307 88-92. Mopalia middendorffii Schr. Amurl. Moll., . 301
93. Mopalia mii.-c<>-a var. porifera Pils. Pilsbry del., . 297
94. Mopalia muscosa var. porifera Pils. Ross del., . 297
95. Mopalia sinuata Cpr. (girdle). Emerton del., . 303 96 (upper fig.). Mopalia sinuata Cpr. Ross del., . 303 96 (lower three figs.'. M"|»;ilia sinuata Cpr. (tail valve)
Emerton del 303
i AIM \v \ i [OH OF I'LVTES. 349
97. M«»pali:i >imint:i < 'pr. < intrnin-di:it»- v;,lvr ). I'iUbry d«-l . J».S. Mopalia imporcata ('pr. (intermediate valve). i'ilsbrv
del ...
99. Mopalia muscosa var. liindsii I'.d. I'iUhry del., 100. Mopalia muscosa var. liindsii P,d. Ro.ss del., . . . li'.MI
PLATE 63.
46. Mopalia musi-osa ( ild. (typical). U. S. Expl. Exped., .
47,48. Mopalia museosa Gld. Ross del., .... 295
49-50. Mopalia muscosa Old. Emerton del., . . . 295
57. Mopalia muscosa var. hindsii Bd. Conch. Icon., . . 296
58, 59. Mopalia lignosa Gld. Ross del., .... 299
60. Mopalia lignosa smooth form. Ross del., . . . 300
61. Mopalia lignosa smooth form. Pilsbry del., . . . 300
62. Mopalia lignosa (vespertina Gld.). U. S. Ex. Exped., . 300
63. Mopalia insignis Newc. (=lignosa Gld.) 300
PLATE 64.
64-68. Mopalia ciliata Sowb. (Monterey Bay). Ross &
Pilsbry del., . . . . . . . .303
69,70,71. Mopalia ciliata var. wosnessenkiiMidd. Mai. Ross. 305
72. Mopalia ciliata var. wosnessenskii Midd. Pilsbry del., . 305
73. Mopalia ciliata var. wosnessenskii Midd. Ross del., . 305 , 74. Mopalia muscosa Gld. Emerton del., .... 295
75. Mopalia acuta Cpr. Ross del., 297
76-79. Mopalia acuta Cpr. (tail valves). Pilsbry del., . . 297 80, 81. Mopalia plumosa Cpr. (=racuta Cpr.). Foord del., . 298 82, 83. Mopalia lignosa form elevata. Ross del., . . . 300
PLATE 65.
73-75. Plaxiphora atlantica V. (tail valve). Pilsbry del., . 313 7H. Plaxiphora setiger King. Conch. Icon., . . .316
77, 78, 79. Plaxiphora setiger King. Emerton & Ross del., 316 80-82. Plaxiphora egregia Ad. P. Z. S., ... 331
PLATE 66.
6, 7. Placiphorella velata Cpr. Emerton del., . . . 306 8-10. Placiphorella velata Cpr. (posterior valve). Pilsbry
del., .... ..... 306
11. Placiphorella velata Cpr. (intermediate valve). Pilsbry
del., 306
12. Placiphorella velata (Insertion-plate, seen from end of
valve). Pilsbry del., 306
13. Placiphorella velata (girdle-hair). Pilsbry del., . . 306
14. Placiphorella borealis Pils. (intermed. valve). Pilsbry del., 309
.0>.")n i:\ri.\NATION OF PLATES.
1 .", Placiphorella borealis Pils. (Insertion-plate seen from end
of valve). Pilsbry del, 309
16, 17. Placiphorella borealis Pils. (posterior valve). Pilsbry
del, 309
18-24. Placophoropsis atlantica V. Tr. Conn. Acad., . . 313
25. Placiphorella petasus Rv. Conch. Icon., . . .311
26, 27. Placiphorella blainvillii Sowb. Conch. Icon., . . 310 28-32. Placiphorella blainvillii Sowb. Emerton del., . .310
PLATE 67.
33-36. Plaxiphora carpenteri Had. Chall. Rep., . . 325
S8. Cha-topleura hahni Rochebr. (=Plaxiphora fremblyi)
B. Cap Horn, 39, 40. Chietopleura frigida Rochebr. (=Plaxiphora setiger,
young). Miss. Cap Horn, 317
41, 42. Chietopleura savatieri Rochebr. (= Plaxiphora setiger)
Miss. Cap Horn, 317
43-46. Plaxiphora simplex Cpr. Chall. Rep.,
PLATE 68.
.">l-54. Plaxiphora biramosa Q. & G., Voy. AstroL, . . 319
55-61 . Plaxiphora superba Cpr. (=biramosa Q.). Emerton del. 319
62, 64. Plaxiphora petholata Sowb. Pilsbry del., . . 323
63, 66. Plaxiphora petholata Sowb. Emerton del., . . 323 65. Plaxiphora petholata Sowb. Ross, del., . . . 323 67. Plaxiphora petholata Sowb. Conch. Illustr., . . . 323 68-72. Plaxiphora glauca Q. & G. Voy. AstroL, . . 326
NOTE.— The Parts of Vol. XIV of the MANUAL were issued to subscribers upon the following dates :
Part 53, including pp. 1- 64, plates 1-15, July 25, 1892, Part 54, " " 65-128, " 16-30, Nov. 25, 1892. Part 55, " "129-208, " 31-40, Feb. 25, 1893. Part 56, " " 209-350, " 41-68, June, 1893.
The Title page, Preface and Introduction to Polyplacophora, accompany Part tffl. J"^ &
END OF VOL. XIV.
POLYPLACOPHORA.
PLATE 1
o'o k> t>t»"\ , >>>* o j >
:J: J
J
,***
io»>««~r'1" »***> ^J
90 <*""*
POLYPLACOPHORA.
PLATE 2
POLYPLACOPHORA.
PLATE 3
POLYPLACOPHORA.
PLATE 4
POLYPLACOPHORA.
PLATE 5
POLYPLACOPHORA.
PLATE 6
POLYPLACOPHORA.
PLATE 7
POLYPLACOPHORA.
PLATE 8
84
POLYPLACOPHORA.
PLATE 9
91
POLYPLACOPHORA.
PLATE 1O
POLYPLACOPHORA.
PLATE 11
POLYPLACOPHORA.
PLATE 12
POLYPLACOPHORA.
PLATE 13
POLYPLACOPHORA.
PLATE 14
86
POLYPLACOPHORA.
PLATE 15
POLYPLACOPHORA.
PLATE 16
POLYPLACOPHORA.
PLATE 17
19
POLYPLACOPHORA.
PLATE 18
POLYPJLACOPHORA.
PLATE 19
1
63
POLYPLACOPHORA.
PLATE 20
.;]
24-
POLYPLACOPHORA.
PLATE 21
POLYPLACOPHORA.
PLATE 22
74-
POLYPLACOPHORA.
PLATE 23
PLATE 24
POLYPLACOPHORA.
I
POLYPLACOPHORA.
PLATE 25
POLYPLACOPHORA.
PLATE 26
I
34
POLYPLACOPHORA.
PL. ATE 27
POLYPLACOPHORA.
PLATE 28
POLYPLACOPHORA.
PLATK
Ib
POLYPLACOPHORA.
4^1
PLATE 3O
POLYPL.ACOPHORA.
PLATE 3!
POLYPLACOPHORA.
PLATE 32
56
POLYPLACOPHORA.
PLATE 33
63
67
POLYPLACOPHORA.
PLATE 34
74
POLYPLACOPHORA.
PLATE 35
POLYPLACOPHORA.
PLATE 36
91
POLYPLACOPHORA.
PLATE 37
POLYPLACOPHORA,
PLATE 38
33
POLYPLACOPHORA.
PLATE 39
POL.YPLACOPHORA.
PLATE 40
•JkJ^JLi-.m^*
14
POLYPLACOPHORA.
PLATE 41
...•••
• - .. ..-•-• .
POLYPLACOPHORA.
PLATE 42
J3J
5R»
34
37
POLYPLACOPHORA.
PLATE 43
POLYPLACOPHORA.
PLATE 44
63
POLYPLACOPHORA.
PLATE 45
|P
POLYPLACOPHORA.
PLATE 46
POLYPLACOPHORA.
PI-ATE 47
POLYPLACOPHORA.
PLATE 48
POLYPLACOPHORA.
PLATE 49
37
POLYPLACOPHORA.
PLATE 5O
48
POLYPLACOPHORA.
PLATE 51
POLYPLACOPHORA.
'-:'i.:i:j.
28
POLYPLACOPHORA.
PLATE 53
1mm
POLYPLACOPHORA.
I -
PLATE 54
.!
Imin
POLYPLACOPHORA.
PLATE 55
POLYPLACOPHORA.
PLATE 56
POLYPLACOPHORA.
POLYPLACOPHORA.
PLATE 58
u ^
POLYPLACOPHORA.
1 mm
* i
31
3E
PLATE 50
26
/27
i lia
POLYPLACOPHORA
PLATE 6O
'*
1mm.
POLYPLACOPHORA.
PLATE 61
PLATE 62
POLYPLACOPHORA.
F
96 N
&
^flf
POLYPLACOPHORA.
PLATE 63
POLYPLACOPHORA.
PLATE 64
POLYPLACOPHORA.
PLATE 65
78
POLYPLACOPHORA.
PLATE 66
?.(T
POLYPLACOPHORA.
PLATE 67
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44
45
41
J 46 ^U
POLYPLACOPHORA
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58':
59", 60
51
68
61
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PLATE 68
54-
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