Presented in Abstract Before the Dtadeniy. K'rbruary 7. 1910

(Presented in abstract before the dtadeniy. k'rbruary 7. 1910)

CONTErTS I'age 1. lntrodu&lon ...... 2 General prlnclples ...... 2 Acknowledgment8 ...... ci 11. Selectlon of a genotype for Cerithirrni RCIISU strlrto...... 0 Ill. Genus Cerith4uni Columnre ...... 10 11'. Ontogenetlc descrlptlon of specles...... 14 A. Recent specles ...... 14 1. Cerifhtum titberosittn proup ...... 14 u. European sperlrs ...... I1 b. Amerlcnn speclc.s ...... 30 2. Genera nnd species related to the Cerllhfurn Ittbrrosum group ...... 33 Vulgocerifhfum ...... Xi B. PlelRtocenlc specks of Vutgwcri/ttiuiii ...... 39 C. Pllocenlc 6pa.lrs of Cerffhirrwr...... 3!) D. Mlocenlc specles ...... 13 1. Cerlfltium ...... 43 2. Vulgocerithfsni ...... 4ci E. Ollgocenlc nnd Eocenlc ~pec'lrs ..... 47 1. Cerfthfum ...... 47 2. Vlchocerllhlrm 57 3. POtUmfdC8 .... 59 4. Potumfdopsh ...... (25 5. Valgocerithfrtm --I1 r r'retaclr rpecle8 of Ccrf/nit8m 79 81, 81 Vl, Phylogmrtlr table of certaln C'wltl,l\ri:c~ 8zi

WoT0. The aotbor alone Is responslblr lor the ie,rnit..,ia*j ~tuthrougboul this artlcle. EDITOR 2 A;Y.V.iLS SEIV YORK ACADEMY OP SCIENCES

I. INTBODUOTION literature of tIie genus Cerithium is already extensive, including papers which treat the subject from both the paleontohgical and the zoological point of view. The genus 1s treated to a greater or less extent in all general works on conchology, but such treatment is confined to descriptions of the genus and of the different specie referred to it, without any attempt to trace phylogenetic relationships, and the same is true, wlth e,wl)tlorlt;, of aleon ontological papers on the subject. Recently Id. Cossmann [1906] has published a monograph on the Cerithiidre, in which he takes account of the relationship between different forins arid IJrVWntS an elaborate classification of the various genera and sub-genera included within the family. B1. Cossmann's conclu~ionsare largely based on characters appearing late in the life history of the individual, and he lays especial stress upon the various features of the aperture. The present paper, being founded upon a different inethc~dof work, as explained below, necessarily reaches conclusions somewhat different from those of M. Cossmann. A complete bibliography of the works consulted in the preparation of this paprr is given on pages 86 to !)l. The principles of phylogenetic development discovered and formulated h,~Hiiclwl, lJ,wtt, ('ope and others haw bwn siiccessfully applied in studies of the pb!.logeny of several groups of greater or less extent, such as Il~att'*stii11rc.a on tlie ('~phalopoda,,Jackson's on the Echinodermata and Grabau'f; on the FIIPI~:P.The prwent papw is an attempt to apply these principlefi in working out the relationship^ of such species of Cmilhium as could be obtained. The fundamental law upon which all the work is bawd iR the law of morphnpenmis, which has been stated by Hyatt' as follows:

.4 natiir:il tl:i~slflr:itloii niay be made by means of a system of analysis In nlilcti thc 1ii1I1vl11u;i1 Is the unlt of romparlson, because Its life In all Its pha~ea. niorpliolopltal aiid phyfilologlcaL bealthy or patholog1c:ll. embryo. larva. ndolestcnt. ailnlt arid old (ontogeny), correlates wlth the morpl~ologlcai and phgslolopltal hlstory of the group to which It belong8 (phylogeny).

:Iceording to thiti prInc.iplc, a study of the life history of individual8 fiirnislie~a ready and mwt rcliahle means of tracing the development of the ~"11~to which thp\. hclong. Henae, in the present investigation, tl~ctartlne pmnt ha!: l~t+jri the study of individual development and a cnmjiBrison of the records thus obtained. Similarity in t]le character .- ___ -.

I A 13TA1-r "GPnrsls of lhc Arlrtlde," p. rlll. 1880. WOOD, PLIYLOaEBY OP CELlTAlY CERITBIIDB 3

and order of introduction of the various features of the shell are indica- tions of relationship, and the comparison of a sufficient number of life histories will furnish a phylogenetic tree whose completeness depenb upon the abundance and perfection of the material available for study. In making such comparisons, it is important to take account of parallelism in development, in consequence of which similar characteristics may appear for a greater or less portion of the life history in individuals belonging to divergent groups. An illustration of this is to be found in Vicinocerithium bouei DESK and V. parallelum sp. nov. of the Eocenic of the Paris basin. These shells are closely similar in the adult and have IJeen referred to the same.specIes, but they differ in developmental history. Both have, in the adult, one extremely prominent spiral around the middle of the whorl, with strong ribs crossing it and a less prominent spiral below. The remainder of the surface is covered with spirals of secondary, tertiary, and higher orders. In the young, V‘icinoceritkiurn boirci has three spirals, the lowest of which is the most prominent (plate VII, fig. 6). Later, in the growth of the shell, finer spirals are intercalated, and all are crossed by ribs. At a still later stage, the upper spiral of the three primaq ones hworncka the most prominent and finally ckvelops into the strong carina of the adult (plate ~111,fig. 6, :Ind platc IY. figs. 5, 6). Vicinocedhium paralldurn also begins with three spirals, of which the lowest one is the most prominent, but ribs are present as won as the third spiral appears (platr wr. figs. 4, 5). TAat(’r,the median spiral becomes as prominent as the lower, and for several volutions the two are equally prominent, while the uprm spiral diminislies in propor- tion, and additional fine spirals are introduced on the shoulder thus formed (pIate VIII, figs. 4, 5). The median spiral continues to increase until it forms the carina of the adult (plate IX, figs. 3, 4), a feature which was formed in the preceding species hy increaee in the ripper spiral of the three primary ones. These shells arc-parallel in the adult, but differ in developmcnt and are to be traced to different ancestors. The phylogenetic rrcord is obscured hy the fict that not all of the lii~toryof a group is expressrd in the ontogeny of a single specie,^. As npw characters are introduced in the evolution of the group the record hromes too long to br repeated during the lifetime of a single individ- rial, and each of the ancestral stages occupies a Rhorter and Rhorter portion of the length of the shell, until some stages disappear altogether. .In individual thii~ehows the adult characteristic^ of its ancestors at an early period of its life history. These facts are expressed as followvs in Jlyatt’s law of acceleration :*

‘A HIATT: “Genrals of the Arleflda II 18x9 4 J.V~ALSXBW YORK ACADEMY OF 6CIE-VCE6

AII modificationsa~,j variations in progressive serles tend to alWilr flmt 1" the adolewent or adult stages of growth, and then tO be inherlted in t3Wcessive descendants at earlier and earlier Stages according t0 the law Of ~cceler*tlon, untl] they either kcome embryonlc, or are crowded Out Of the orS;1uiz~t*on* and replaced in the development by characterlstirs of later Origin. This law is well illustrated in the development of two Paris Basin shells, Pohmidopsis tn:canymta LaafAacK of the Calcaire Grossier and Potamidopsis roissyi D~srr.of the Sables Moyens. In the young, the surface ornainentation of the latter species consists of two rows of nodes, the loner beiag thr more prominent. The lianle is true of the young p. trkarinata, but this stage lasts much longer in the latter than in the former species. The stage with two rows of nodes is followed by one in which there is an additional row of fine nodes intercalated between the two, and the lowest row is still the most prominent. At about the ninth volution of 1'. roiss!yi this ornamentation is fully developed, and it represents the adult ornamentation of P. tricarinata, which is found at a lower geological horizon. The adult characteristics of P. lricarinala last for hardly more than one volution on P. roiqi, which soon develops its own chararteristic adult ornamentation of three rows of nodes, the uppermost of which are largrst and transvemrly elongatcd. (See Deshages, 1824. plate L. fig. 13.) P. Irir.arinn/a is the anccstor from which P. roissyi drvrloped. and thc latter records this fact in its ontogenv. Two indioiduals belonging t.o the same phyletic series and living during the same time period frequently do not reach the same degree of complexity in structure. One may retain its primitive characteristice until late in its life hidory, only diverging from the ancestral type on bwoming fully adult, while another may pam through its ancestral stages early in life and fihow a long succession of characteristics of later origin. The former is retarded in its development in comparison with the latter. Cerithium tubcrosum is an illustration of a retarded shell, retaining, as it dorR, the two rqi~allystrong spirals until the tenth volution, the whorls only arquiring thrir acute angled outline on the twelfth volution. Ce- rithivm. adan,soni paws through the same ancestral stages as C. tubor- osum. but lofies the ohtuae angled outline of the whorl8 at about the sixth solution and aftrr that acqiiires nodes, blunt ppincs and numerolls ad&- ha]fipirala. Jt is a highlv accelerated rwent shell. Arceleration and retardation are expressed not only in the ontogeny of the individual as a whole, hut each character may be independently WceleratPd or retarded. Cerdhiurn gmciliforrne (Tryon, 1887, plate nI1. fig. 77) retains the obtusr anpled outline of the whorls to the ninth vollltion. white c. Pchinnhm (Rohelt, 1898, plate x;g, fig. 6) loRa 1V0017, PH YLOUENY OF CERTAIN CERlTfflfDrE' 5

this type of outline at about the seventh volution. C. graciliforme is therefore a more retarded shell than C. echinutum in this respect. In the acquisition of nodes, however, it is accelerated, for it acquires noda on the ninth volution, while C. echimtum does not develop them until the thirteenth volution. This differential acceleration and retardation often produces a wide difference in the appearancq of adult shells, without the introduction of any new character. Individuals having the same development for a greater or less portion of their life history, but differing in the adolescent or adult stages, mag be regarded as divergent descendants from the same ancbtral stock. A striking illustration of such divergence is found among recent species of Cerithium in thegToup of which C. tzcberosum may be taken as a type. In addition to the types of variation already noted, there is a kind of individual variation which seem to difkr from all, and that IS in the slight accentuation of the characters of the shell from their earlie& appearance to the lmt volution. This is seen in individuals of Cerithzum lamellosum, some of which show secondary spirals distinctly on all the whorls, while on others these spirals are but faintly indicated. This may be due to 6ome condition in the environment, possibly to more lime in the water or to better food supply in the case of the well-marked individuals, or it may be due only to an inherent tendency to variation. Acceleration and retardation and the introduction of new characters may cause divergence sufficient to serve as a basis for the separation of species, or they may appear to a less degree in individuals referred to the same species. Where many individuals Hro present, we find gradations in the various characters compelling us to establish varieties, and the more extensive the material the more inwnsible the gradations become, so that if our eollcctiom wire 8ufficicntI.v clxtcnaivc, it aou~t~c~ou~it~rss ~n: pofisible to establish a perfect gradational series among various epecies of Crrithivm,, :i~in the classic example of the Planorbis of Steinheim.s As might be expected, the greatest difficulty encountered in determining the phylogeny of Cerithium lie8 been due to the scarcity of material. Tt has been impossible to ~ecurespecimens of shells from the early Meso- zoic horizons which might be expected to furnifih the ancefitors of the forms occurring in siidi aI~itncIanc-c in the Eocenic. A siniilar cIifficultv arim in connection with late Tertiary and early Quaternary matmial in which we should expect to find the connecting links between Eocenic and recent Rpecies. Tn the absence of specimens of shells, figures and dc-, scription8 have bwn freclv iised, but the figures of the earlv portions of

' .4. IlrdTi. Ifern. Boston Soe. Net. Blst. 1880. 6 ANSALS ,VE’lf YOl

11. Sl

under the name of Cerithium erythrceonense and by Sowerby [1855] and Reeve [1866] 88 Cerithium tuberosum. Adanson [1767] described and figured a shell from Senegal which he believed to be identical with that of Columnae. His figure closely resembles Cerithium tuberosum, except in the aperture, which is more like that of the shell from Senegal described by BruguiGre as Cerithiurn adansoni. Adanson was describing a shell collected by himself at Senegal, and his description seems to indicate quite definitely that his shell is really C. adunsoni BRIJOUIBEE,since it mentions the strongly spinose tubercles not found on C. tuberosurn and gives the size as two inches, or about 50 mm. The youngest specimen of C. tuberosum seen in the collections studied was 67 mm. long, and full-grown individuals are 61 mm. or more in length. The similarity in the figures may perhaps be ac- counted for by a tendency on the part of the artist to imitate a figure already published and believed to be of the same species. Adanson named his shell siinply "Le Cerite," and this name woiild not stand, since it does not conform to the binomial nomenclature. The first published description of the genus Cedhiurn is by Bruguihre [1?92]. He divides the genus into three groups, the first of which corresponds to I.erlagus li~liixand the wwiid io Crrilhium pensu stricto. The first species of this second group is Cerithium nodulosum, which the author believed to be of the same species as C. tuberosum COLUYNX, since he cites the latter species in his synonymy. Thc description, however, corresponds with C. nodulosum. as the name is now applied. The second species of this group is C. udunsoni. the description of which cor- rwpontls closcly with that of "1,~ ('vritc," It! .Idanson, and Bruguibre fitates definitel? that he is describing a shell of the same speciea as Adan- son's shell. At a still earlier date Martyn [I7841 figured under the generic name of Clava four species which Dall [ 1907, p. 3661 now refers to Cerithium, as followe :

1. Clam rrrgata MABTYN= bl ttrrs n.-pi.r l,~sxE. 2. Clava herculea MAETYN = CeritLiirin ehetrlnum BRUQUI~EE 3. Clava maculata MABTYN= Cerlthirtm clava BEUQCIBEE. 4. ("nra rttbua MABTYN= Ceriihittnt acltinntrtm LAMAECK.

On the strength of these figures, Dsll libid., p. 3681 claims for hlartyn the first recognition of the genus Cerithium, but Martyn published no descriptions either generic or specific. and it hardly peenis that thew fig- urea alone furnish a valid reason for changing the name of the genus from Cen'thium to Clava MARTYN. Clava has long been established as 8 ANN.~LS.y,!$lv WItK ACADEMY OF SCIENCES the name of a genus of hydroids, and the confusion that would arise in the literature furnishes another reason for avoiding such a change. In the first published description of the genus Cerdhivm by Bruguibre no genotype was designated, and the fiat to make a definite WlNtion hmarck [1799].‘ He chose Mufez duco LINN~,which waa described by BruguiCre wit11 the name of Cerite chenille. This shell belongs to the first of the three groups described by BruguiBre, and it might well remain the type of that group to which the name Pseudovertagw has since been applied. It doea not belong in the same group with the shell to which Columne gave the name of Cerithium, as will be aeen by comparing the life histories of the two species as given on plate III, figs. 2, 3, 4; plate IV, figs. 2, 3; plate v, figs. 1, 2; plate 111, fig. 6; plate IV, figs. 6, 7; plate v, figs. 5, 6, and plate VI, fige. 4, 5. Lamarck himself seems to have been dissatisfied with his own choice of a genotype, for two years later [1801, p. 851 he redescribed the genus and mentioned Cehthium nodulosum as an example of it. Later authors have adjusted the claims of their predecessors in various ways. Biost credit the genus to Bruguihre, but others refer it to La- rnarck or Adanson. A few of these may be mentioned: thus Montfort [1810] credits the grnus to Lamarck, choosing the genotype selected by him in 1799. Link [1807] and Schumacher [l817] solve the difficulty by dividing the genus into two groups, the former following Lnmarck, in 1 ;!)!I, for his first group, and Bruguih, with Ccrithiuni adannoni as an example of his secoDd group, to which he gives the name Atuco. Schu- rnac1ic.r rrtaim the name Ccrithivm for both his groups, crediting them to Lamarck, with C. ollrro as genotype for one and C. noddomm for the other. Among the author3 who refer the genus to Adanson are Deshayes 1IXY-l 1. ~I’OrI~ignyIlnlP-18.1.) I. Soa.rrl)y [IH55], Fischrr [I81177 and Trm 1181171. RrnpiiPrr, king the fint to describe the gem8 m Ruth, ig still more nidrlv recognized, and a few of the authors who have fol- Io\Vl~il h1111 Rri’ S\\mfisiiri I IfblOl. Ilrrrc [1S66], Cofisrnann []9()6] and Dall [1907]. Jn thP choicci of R pi~notvpeequal divemity is shown, for Fischer, while hr rc.fer6 the peniiri tr) Ailanson, choose8 C. nodulosm as the genotype. nrPha!.PS ifi consiptent in choosing for the type of the genus C. dansoni. ‘If fliopr ~h rrfrr th~ynus to Rniguikre, SwainRon and CofiRmann 1 h(ll)w ‘’. nljrl7/lowtj? RINI hll and Dautzrnhrrg and Dollfur! 11882- lsg.;] (~ll(~~~~i~1Ii:w.r ~///(o I,IYY~ 2s t)lp type of the genllA, Sllmmarizing the alreadv given, it appears that column= was . . .- __

‘7% mhnr ha8 hrm mnlh 1.. .CP rhh work. and la Inflphtd fo all l,~~,,D, 304, rsir IhP ri4prpnrp WOOD, PHYLOGENY OP CERTAIN CERlTHIIDl 9 the first to propose the name Cerithium, which he did in connection with 8 description and an easily determinable figure of a well-known speciw. He gave it a name which conforiiiv to the Linnrean system of nomenclature, and it appears to the writer that these facta are sufEcient ground for referring the genus to Columnre. Apparently the only reason for discrediting his work and referring the genus to a later author is found in the rule of the lnternational Congress of Z~Ol~gists,according to which the date 1768 is taken as the starting point of the binomial nomenclature. This rule is useful, but to enforce it indiscriminately would do great in- justice to the pioneers in science whose work conforms with the standards at present in use. This is especially true when, as in the present case, there are additional reasons for recognizing the earlier work. In actual practice the rule is not closely followed, since many genera described pre- vious to the year 1758 are still retained under the name of the original author. For example, among the Cephalopoda we have Belcmnites LIS- TER, 1678; Orthoceras BREYN,1732; Lituites BBEYN,1732, and among Oastropoda Planorbis OUETTAUD,1756, and Halwtb LINN~C,1735. Fur- thermore, the reference of the genus to Columnre would have the great practical advantage of settling at once the vexed question of a genotype, and this type is of such a character that it would, on the basis of phylogenetic studies, retain within the genus Cerithium a large number of the Rpeci& known by that name throughout the literature of the subject. ‘I’hc work of .ltlunson, like that of (’oliirnn;r, is pre-I,inn:pan, and it furthermore fails to conform to the binomial nomenclature. 1 f the rule of discrediting prv-l,innx~;iiiclcwriptinns IJC rigidly adhered to, the genus would Iir refrrred to Rruguihrv, and the clioice of Cerithium ??OdUkMUm 8s genotype seems to come nr:irrst to that author’s own con- crption of the genun. The choice of dlirrer aluro for a genotype, a8 at first fiuggeeted hy lmiarck [1799], wniild rrwlt in substituting the name Cprilhiunz for Pseudovertagus and the use of a new name for the group to which the former WBR originally applied. This would cause great confufiion in the literatiirr and rn:ik(J the pnus a different one from what mas intended h,v the early writers on the subject, Rince RruguiBre was nln-ioiidy trying to fnllow 1v)t 11 (*oIi~nin:~and Adanson in dcscrihing first, C. nodulosum, which he hrlirvrd to be identical with Columnac’s PJI~II, and wcond, C‘. nhsoni. whi~~hwas “I,? Ceritc” of Adansnn. He merely fell into the cnmmon errnr of including under one name piips of Fliells which he himself recognized tn he different. Ccri!hiim nodi/\o.w~i~Ifcar!: a siiperficial rewmhlancc to C. tuhrm,xvm and ha9 heen considerrd by snmc aiithorg to he of the aame Rpecieir. Tt i~,hnwcver, quite distinct. According to the youngest Rpwimens of 10 ANNdLS NEW YOllK ACADEMY OF SClE’.?”cE’8 C. n~dulosurnat first obtainable, it seemed that the two species belonged to the same phjletic series, Imt the absence of ribs on a somewhat younger individual, received later, throws some doubt upon this supposed relationship. The point can only be determined by a study of younger stages of C. nodulosum than are now available, and in cue the latter shell proves to be different in its development from C. hberosum, it must represent a very restricted group, for among species now referred to Cedthium the absence of ribs on individuals having a well developed shoulder is an extremely rare feature. In this case also, with C. nodulosum as genotype, the name Cerithivm would be used in a very restricted sense, and a

ncw name \sould haw to 1x4 given to the genus as understood by Coluinnm and Bruguibre. For the purposes of this paper, Cerithium tuberosum CoLvai?i,f: will be used as a standard of comparison for other species of the genus.

k 00 I G< rtlhtu.ra I*.<,.. (’opy of (~IUIIIII~~”, iriillai dr;ure 1

After the description of Humnum maxiin~umand mention of other speciea of Buccinum, Colurnna. refers to this species as followe : Sed rarlore~n hnnc parol HIIIY~IIIItiilwrosl cnndldl. ntl Ccrlthln referendam. or18 rnnrglnc supra tuhulun~14:it:i. PI Incunlhenn non lnuersn ut In nlljs mngnls WOOD, PHYLOGENY OF CEItTAfS CE~tlT€lIlD& 11 efflglem omittere noluimus, quanimus hulusmflL dlas dlfferentlas habeamus, Colore clnero orbltas depressloribus. m3gIs densls mfnutisque tuberculls nsperas.

While this description is meager, it is sufficient, with the aid of the figure, for the identification of the species designated. The character- ization of the shal as a small one excludes Cerithium nodulosum. with which it has been confused. The reference to the margin of the mouth as raised above the canal and resting upon it is like C. tuberosum and unlike C. adansoni. The figure also resembles C. tuberosuni in its high spire, in the character of the aperture iind of the ornanlentatinn, so far as this is indicated by the imperfect figure. Description of Cerithium by Bruguibre : Genre de coyullles untv:ilves, uiii1wui:iire. h splre regulic're, qul a Inour c*nr:ictPre. 1:ne roqullle turrl(wl(u. l'uuwrttirv oldiqiie. trriiiliiPe h I:! bane par un cnnnl etrolt, totalement recourb(S, ou uioyeiiiieuirut revourM. ou drolt et trc'scourt, rii:ils jamals @chancre.

Genotype selected by Lamarck, 1 ;!I!), .l/ure.c uluco IJNNB; 1801, Cerithiurn nodulosum BRUQIXEI~E. The protoconch of the genus Ccrttkium has been observed in many, fipecies and is found to be miforin 111 chirwtor. It forms a low, regular spiral of usuollv about one and onr-half volutions. The limits of the protoconch are not sharply defined, as tlie ornament begins faintly at first and becomes gradually fit rongrr, I)nt for convenience the protoconch has been assumedyo end where the first tracw of ornament appear. I'rac- tically the only &firrekc found in tlw wrliest whorls of the specie8 studied is in the extent of the mooth portion of the shell, which varies from one and one-fourth to one and one-half volutions. This is due to difference in degree of acceleration, the more accelerated forms having thr ornamentation cro\vrlrd IJ;l('li to ;III ~*;irl\st;lgr in shc~llgrowth.

The fiurfacr omainrntation of ('f,/,i//iii/m i.IInsists of spirals, ribs an(] nodee, the great diversity ohservahle in tlir ornarnrntation of tlie different specie8 being due to the relative dcwlopmrnt which each of these features attains. In forms suficientl! rrtartlrd to show the order of introduction of the various features of tIw ornarnrntation, it appears to begin as one spiral, or in accelerated forms ali more than one, additional spirals coming in ahove the first. Ribs next apprar anti nodes are formed Iy the concentration of matrrial whrre thr rihp and fipipls cross. ln a few cases ribe appear after the first and hefore the formation of a wmnd ~piral,but in nn caw Iiav~riIjc Iwn olwrvrd I)dorr thc apprarancr of at least one spiral. Intercalatrd qpiral5 ma! come in either before or aftrr 12 A&K.~L~XBIV I'OItK SCdDEIY OF SCIENCE" the introduction of ribs, and they often become extremely xmmmus- mile the order of introduction of the types of surface ornamentation i8 fairly constant, the precise volution at which a new feature will appear is dependent on the degree of acceleration which the shell has attained and ofkn shows considerable variation within the same Linman species. In highly accelerated forme, both spirals and ribs may appear together at the close of the protoconch stage. This is seen in Cen'thium adansoni, plate III, fig. 3. The amount of embracing of the whorh in shells of this genus varies within considerable limits, but as a rule the body volution is shorter than the remainder of the spire. The aperture is oval, with an oblique, more or less widely open anterior canal. Primitive forms have no posterior tooth, but in some E;ocenic and later fornis a projection of the callus of the inner lip forms a dlstinct tooth which defines a short canal between itself and the outer lip. In the earlier Iiteruturc~of the subject, the name Certthium was applied to all forms having in conimon the characters of a high spire, a short bodv whorl and a short anr(mw canal, although Rruguih himself recognized the heterogeneous character of the genus, for he separated it into three goups which are now properly recognized as distinct genera. Fur- ther siihdivisinn has Iicc*n foiind newssary from time to time, until in If. Cossmann's Essajs de Pal~oconchologie, volume 7, after the separation of several groiips of fitniilv rank, we find seventeen genera, thirty- ~icwl)gcnera ~rndforty-fiw rwtionp. ('hoo~ingCwithium nodulasunz RIKG~~IFSREas the grnotype, lf. Coss- mann lays efipwial atresfi upon the projecting tooth on the anterior portion of thr outer lip, and he restricts the genus so as to include those forms in which thip tooth rrosfies the opening of the canal. This ena- hlrs him to place onlv two spwies within the genus, the genot>v and Ccritlitiim crythmonmsc (= C. tirhcrosum), hut a close study of the anfirior tooth wems to indicate that its importance as a baRis for classification has hrrn gnwtlu wrrwfjmated. It appears on the last portion of the body whorl. a position in which the hiphrst depree of variation in the +ll ip to II~i~pc~r.trd. nn~l fv:ltnrrr: appearing at thiR dage sho111d srrve as rCaROnR for qarating ml rnemhrm of evolntionarv txriefl, but not for llnltlilg pp(+p as rrnrw. if thr (XlnaFification ifi to he A natural on+ that iF, had an cnmmnnit,v nf desrent. The tooth is formed hy the mnrp rapid wwth of thr antcrior part nf the outer lip, and when a 'PimI is present on thip part nf thr shell, it often determinm the point at which an extra RmOllnt of ralcareouA material is deposited. The de- WOOD, PHYLOGEXY OF CEltTAlY CEItlTHllDA3 13 velopment of this tooth is extremely variable among individuals undoubtedly of the same species; for example, among six adult individuals of C. 1 nodulosum showing no trace of fracture, two develop this feature to a very slight extent and do not form a tooth which crosses the aperture. C. echinatum is referred to a difleriAnt section on account of the less development of this tooth, but certain individuals have the tooth developed to a greater extent than some specimens of C. nodulosum. Not only is the tooth variously developed in species which are shown by their ontogeny to be related, such as C’. tuberosum and C. echinatum. but it is strongly developed in species undoubtedly of different descent ; for example, Pseudovertagw aluco and related species have such a tooth very strongly developed, yet the wide difference between the ontogeny of Psedovertagus aluco and Cen’thium 1 uberosum will be readily appre- ciated by comparing the figures of C. tciberosum in the first column of plates 1x1 to VI with those of Pseudovertagus aluco in the fourth column of the same plates. Of the genera,and subgenera of Cerithiidc alreadi established, therc will he considered in this paper only the Cerithium tuberosum group and others closely related to it. In the description of species which follow no attempt has heen made to give a complete synonymy. In each case the original description or a refercnce to it is given, and also a reference to a good modern description. Where necessary to make the identification of the species clearer, additional references are given. Descriptions arc lmed on one individual which may he considered tvpical of the gperic.s, hut where variations such afi differences in color, in the nunihcr of variccs and tho like are cl~rac- terifitic featurea, other individuals are considered. Measurementcl are also from one individiial, ufiuallv the largrst of those referred to the species. The method of taking mea~ureinrnt~of the apical angle is similar to that described hy d’0rhigny [1812-1843, pp. 10-141, with the exception that in the case of convex or concave shells two measurement8 are given rqmwnting the extreme anples ohtainrd. and. aR nearlv as possi- ble, the volution at which thr chango takrs place. The ~iitiiralangle is measured a8 drscrihed hy d’Orhignr. hnldinp the apertilrr of tho shell downward and taking the iipper anplc nlad~I)! the ~iitiirewith the right side of the shrll in deitral fnrnw 2nd thr. ivft cidv in sinistral forms. 14 ANNALS XEIY YORK .4CAUEUY OP SCIENCE8

IV. ONTOQE~ETICDESCRIPTION OF SPECIES

d. =CENT SPECIE8

1. Cerilhium tuberosum Group

a. European Species

Cerithium tuberosum Colionn@

Plate I; plate 11, fig. 4: plate III, fig. -I : plate IV, fig. 1 ; plate VI, figs. 1, 2.

1616. Cerifhfum [Uuccfnuni J futmosuni FABIICOLUMN&, De aquntlllbua, pp. 53. 57. IM3. Cetifltiut>~eryfttraunc.rrsc IAMARCK, Bnlni:~ur sans vertebres, 6d. 2, IX, %2. 1S5. Crrifhiani tubero8rriri SOIVEIIBY.T11es:iorus Conch., 11, 855, pl. 178. Rg. 49. 1866. Cerifhiuai fuberosum I~EEVL.Conch. Iconlca, XV, pl. I. Rg. 5, No. 6. 18!r8. Cerithiuftt et’vihrtrr,i,(.J,nc ICOBELT. Syst. Conch.-Cabinet von Martlni u. Chemnitz, IM. I. Atith. 26, 78. pl. 15. figs. 2. 3. 1887. t’eritkiuni eryfIrrcrotirii,vc TRI’ON,Manual of Conch., IX, 123, p1. 20, Rg. 16. 1WG. Cerilhium rryfiirro~ieiizeCOSSMA~X, ESS:IIS de I’al&conch.. VII, 67.

The original description II~Falii (‘olmmp is given under the discus- sion of the genus.

.\lrani.HelicmTs : Imgtti. fs 111111. : Krwtest di:inieter. Z3 mm.; apical angle, 34”. rhn~i~igon ttie 9th vo~urionto ‘Hr.5’; wtur:il angle, 91”. (‘orun : 1’:iIr brow or brownisli yellow.

‘The protoconch is not preserved on any of the specimens obtainable. The first volution retained is .7 mm. in diameter, and this corresponda in size with the first volution beyond the protoconch of Cerithium adansoni. The surface features arc entirely obliterated on this volution, but the next shows traces of the ornamentation, which is apparently the Bame as that of C. adansoni at thc same age. The fourth volution has two fitrong spirals, the uppvr of which definee the shoulder, with one spiral intcrralated between them. There are also four equal ~piralsabove and two below the primary onvs. :\I1 the fipirals are crofified by ribs, of which there are nine on this volution. On the eucceeding volutions more spirals are added on the shouldrr and the lower dope of the whorh, and their nnmber is also incrcwed hy intercalation between those already ex- iRting. At ahout the eighth rollition the spirale become much crowded, and are raisrd into a strong ridge just below the suture. The same tpe of ornamentation persids for eleven volutions, but on the twelfth the Inam of the tao equal spirals herornee weaker, and the outline of the WOOD, PHYL00E.I'Y OP CERTAIN CERITHllDl 15 whorl changes from an obtuse angle to one both of whose sides stand at angles of about 45" with the axis of the shell. This tendency increases until, on the body whorl, the lower primary spiral is inconspicuous, and the upper forms the most projecting portion of the strong nodes into which the ribs have become contracted. The sub-sutural ridge above described is, on this volution, raised at short intervals into a row of smaller nodes, and on the lower portion of the body whorl there are three strong nodose ridges formed, like the subsutural ridge, of groups of fine spirals. On the under side of the body whorl ribs and nodes are nearly obliterated along the surface upon which the animal rested when with- drawn into its shell ; but just beyond this area, on the side of the volution opposite the outer lip, the surface is raised into a strong varix. The aperture is oval, with a strong posterior tooth. The outer lip is slightly flaring, with its margin crenulated by the spirals of the outer surface. .The lower portion of the outer lip grows more rapidly than the upper portion, and the lowest of the nodose ridges is produced into a toothlike process which, in some individuals, crosses the opening of the anterior canal. The length of this process varies considerably in different specimens of the species. The inner lip has a strong callus. The anterior canal is long and comparatively narrow.

IIOBIZONAND IDCALITIEB : Recent. Red Sen find Indlan Ocean. So. 20124, Columbls Unlrersltp collertlon.

REarAaKs: Cerithium tuberosum is especially well adapted to serve as a type of the group of shells to which it belongs, since it is a retarded form pasaing through the various stares in its development slowly and retaining primitive characteristics until a late period of its life.

Cerithium 7 nodulosum RritguiEre

Plate 111, fig. 5; plate IV. figs. 4, 6.

1792. C?r{tRlum i?nda/onsm RRi'GviDRF. Illst. n:iturelle des Vera, Encycl. With., 1. pt. 2. 47R. 1887. Cerlthfvm nodirlonirni Tn~ox.JI~IIU;II of Conch., IX, 122, pl. 19, figs. 13. 14: pl. 20, flg. 15. IRRR. CrrWtllcm nodir/ostm 1Consl.T. SyPt. ('onch.-Cabloet von Martlnl u. Chem- nits. Rd. 1. Ahth. 26, 76. pl. 1.5. flc. 1. I!Kl6. Cerflhfrmrtndirlostmm COSRMAISN.Easnl~ de Pal&xo~ch.Comp.. V11. 66.

M~ABUREMEXTB: Length. 95 mm.: grentest dlameter. 47 mm. ; aplca) angle. 37'; sutural angle, 84". COILTI: GrnylRh alilte, more or lwi closely covered wlth lntermpted bands 2nd patrhea of dark brown. 16 ,4.v.vr1Ls X~~IV)'01t1i .1C.iI)E.if 1' OF SCIE.\CES The youngat volution avaifable for study is 1.9 rn.in diameter, and it is probable that several volutions have been broken away above this. It has a sharply angled outline, with the most pr0JWtjng portion Sligbtlg above the middle of the whorl. It is ornamented with three strong, eon- tinuous spirals, the uppermost of which is stronger than the others. Two firier spirals are present 011 the shoulder, and one is visible just above the suture. The entire surface is roughened by exceedingly fine, thread-like costie crossing the spirals at right angles. They are too fine and too closel? set to appear like ribs, and ribs of the usual kind are entirely absent at this stage. The ornamentation remains similar in type, with the intercalation of finer spirale between those already existing, until the sixth volution, on which widely spaced ribs appear. At this stage the volution is about 6 mm. in diameter. The fine spirals increase rapidly in number, and on the later volutions the primary spirals seem to be made up of clusters of finer spirals with the clusters separated by deep, smooth grooves. At about the ninth volution the median of the three spirals becomes almost as strong as the uppermost spiral, so that for two or three volutions the obtuse angled outline of the whorl characteristic of Ceritkium is suggested. The upper spiral, however, soon becomes again the most prominent one, and thiA tendency increases until, on the I~od,v volution, this spiral forms the margin of Very large, blunt, flat- topped nodes, with the ribs nearly obsolete above and below them. On the late whorls the finer spirals are sometimes confluent and the former cluster becomes a broad, flattened ridge defined by a narrow groove on either side. The body volution below the nodes bears three broad nodose spirals. The api~tureis oval, with the outer lip flaring and thrown into Rtrong folds by the coarse spirals of the outer surface. The lowest of the spirals on the bodv whorl is cometimes produced to FUC~an extent that it forms a projecting tooth which crosses the opening of the canal. The inner lip bears a Rtrong callus with a prominent tooth near the posterior portion of the aperture. The fiiphonal canal is broad and deep and n lightly hrnt backward.

rfoIII7.oN AND II)CAI.ITIT.R I{cwnt. Moliirrns. Phlllpplnm. Iodlnn Orenn. No. 40203, Columbln I'nlrerdty collection. Tl~ryonng Indlvldunl flmired Is from tbe erhlbltlon rollcctlon of the MUR~UI,, of Compnrntlve 7kdlOgy.

REWRKB: Although the adult of thiR spwies bears some resemblance to CeAthkm ihbefosum.. its drrclopmrnt is unlike that of any species of hithiids studied. Thr formation of a distinct Ahoiilder 80 long before the appearanre of ribs and lhc prrsence of the fine costa crossing the WOOD, I’Iil’LOOBA‘l’ OF C‘EIL1‘Al.Y CEXlTHllDb 17 spirah are features which have not been observed elsewhere. So far aa the information at present available goes, it would appear that C. ? no&- losum ie the sole representative known of a dietinct genus, but it ia left for the present in the genus Cerithium, awaiting an opportunity to etudy still younger stages of the shell and to obtain other ahella which will throw light upon this peculiar type of development.

Cerithium adansoni Bruguibre

Plate 1 ; plate 11, fig. 3; plate 111, figs. 2. :$, 4 ; plate IV, figs. 2, 3 : plate v, figs. 1, 2. 1757. “18 (‘erlte“ ADANSON.Illstolre S:iturelle du Sen6gal. 152, p1. 10, flg. 2. I i!]?. C‘erifhiim adonsorii BRL.OI.IBBE.flist. Nat. des Vers, Ency. Metbod., I. pt. 2, 4i9. IN%. (’er{thinni adotraorii SOWERBY,‘I’liefiaurus Concb., 11, pl. 178, flg. 45. I 8!B. (’crlfkltrni odonscmi I

The following is Adanson’s description of “TR Cerite” : F:iblur Colutniia s’est rrrvl du iitot grec I:itluise Cerlthluni pour deflgurer une rspre du genre des t.oc~ulll:igrsque je v:ils dkrlre WUAle nom roinmun de Cerlte. ],:I twlullle de rette rspiw n‘:i guPrvw que tleux poures dr longneur rt une fiiis itiolns de l;trgeur. OII ti’g cmnpte clue doozr splres. renfllw d:iiis Icur tiillleu. qul eRt g:trnl d‘un r:itig dr bussettes nswz grosses. Flcv&s sur une cote parallel n sa longueur. IR restr de lenr surfavo est etitonrP rtr dlr ;1 tiorize prtlt fllcts lwii CIPVFH. La swoitde splre Imrte quelqorfols uit K:I’OR 111~1irreIrtmr la gauche. [,:I longueur dii soiiiiiirt surp:isfie prrsqnr unr fols sn lnrgeur rt In premIi?re slvlre. I.’oitwrttirr (.st rx:trtrnient ronde. et pnrolt henucoup plus evn& que la Iirfd4rntr. pnrcr qri’rlle fie portr prwqu’ rittfPrenient bore de In coqullle, aur S:I qlrolte. soti ~~:in:ilIiiffriritr est rreusE eii d~~iiil-ryllndre,rmuwrt en pnrtle 11:tr IIIIP ci)te :ISSW grosw. rlrvfie sur I:I h:ise de In IEvre gnurlie. IR canal wphirur rnt rrserrf. et dr nioltif plus profond que Inrge. I.;] IPV:I’P droit n’rst p:is SPlIS~~~~CJillPlitprolonpCe dnns s:i p:irtlr fiupbrleurr. ,.I dlr nr fornir p:tw t’:tnvrtit roninie dnii~In preinlPre esNre. 1,:i li.vrr g:iti~~li~~tt’rut 1):is no11 liltis rrplliv ~~oii~iiicI:I slrnnc :.cllr est rmu- > NIV sritlrntc~iitp:ir nnr hnir mnrt<~.ii1:iIe f~~:ilsse.et rrlrrCr en IMN d’un Blet ;~SSI*Y. crns qnl tournc eri dd:ins de I:\ roquille. S:I w~il~iirrat 111:i ncliv. s:ins 111~1:iiip~tl:in?i lrti jeiiorn. rt ICgFrc~n~enttwbh *P vlt :IUSP~d:tnr; 1:) T’I’IPC iii:iI* on nr In volt qu.Pn prtlte qiinntlt8 (IAIIG lr tleiive (;:it~il~l~.vis-21 ~lslr voniptoir 4‘AIhrdi 18 A .v.~AL,~XBW YORK ACAIIEM Y OF SCIENCES Tfie &cription of this species given by Bruguihe is closely similar to that of Adanson, and much of it is even worded in the same way. Prac- tically the only addition made by Bruguibre was in giving the species a binomial name. - .-

~~~CASL'HEMENTS: )anpill. 4:: IIIIII. : greatest dlmeter. 3 mm.: apical angle, ,yy to the ejphtll volutioIl. r~t:ingiiigto 31.5" : sutural mgIe. 72.5". Corm: White. sparingly dotted with pale brown. The protoconch of Cerifhium adansoni consists of about one and one- fourth volutions. The ornamentation begins as two spirals crossed by distant ribs on the first volution beyond the protoconch (plate HI, fig. 2). The second volution bears three fine spirals on the shoulder. These are increased by a fourth fine spiral on the third volution, and an intercalated spiral appears between the two primary ones. Tertiary spirals and those of higher order are soon developed, and these hespirals do not inellease greatly in size, but thev become extremely numerous, so that the entire surface of the adult is covered with thread-like cosh. On the fourth voliition, just below the upper suture, there is an elevk'tion of the surface to form a coarse spiral which carries with it the fine spirals already existing. J,atrr in the life of the shell other coarse spirals arise in a similar manner on the Rhoulder and below the two primary spirals. The lower of the primarv spirals becomes gradually weaker and the upper more prominent, until at about the Rixth volution the outline of the whorl has lost its vertical element formed by the two equal spirals and has become nn acute angle. On the next volution the center of the rib becomes fin prominent that it might almost he cnlled a spine, and on this volution also rows of large nodes are formed bv the breaking up of the coarse spiral8 jud helow the upper suture and above the lower one. On the rlevcnth roliition there are three coarse spirals above and thrw below the central extrcvnrly prominent one, all of which are irregularly nodose. The median spiral of the body volution is spinose on the dorsal side, ht on the ventral sidr the Rpines are reprmrnted bv low node8 onlv. Below the prnrninrnt qiiral on the bodv rolution there are Rix or more cnarw spiral!: with finw inti~rcalatrdoncs. and thc n~holci!: cnvered, likr the rest of the siirfa~~.with the fine cogtz described above.

The apert~~reiR a broad oval in outline. The outer lip i8 thick, eome what flaring, and rrennlated bv the spiral# of the outer ~iirface. The inner lip has a thick callii~.raised into a Ptrnng hhint tooth mhich. with the olh~lip. forma a short canal at the poderinr end of the aperture. The anterior canal ip short and dightlv ciirved, and its opening je nar- rowed h!. the rapid prnath nf the lower portion of thr outer lip. ThiR lYOOL), PEYLOQE'KY OF L'EItTAIS CERITHIIDA' 19

growth d&s not, however, form a distinct tooth as in Cen'thium tuber- owm and some fomof C. echinutum.

HORILONAND ~CALITIEB:Recent. Senegal, west coast of Afrlca and spar. lngly near the mouth of the Gambia Rlver. 1M. Cossmann [1906, p. 661 as- sumes that this shell Is a fresh-water form, but thls Is hardly borne out by the statement of Adanson, who collected the animals in thelr natlve locality. Accordlng to his account of the habltat quoted above, It seems that the animal is typlcally marine, and comparatlvely few lndlviduals have rnlgrated up the Gambln Rlver. No. 20125. Columbia Unlverslty collectlon. Museum of Comparatlve Zoalogy, museum collectlon.

REXABHS: This shell, from the protoconch to the seventh volution, corresponds exactly in development with Cerithium tuberosum. It is, however, a more accelerated shell, since the stage with two equal spirals persists in C. tuberomn for ten volutions, while in C. adansoni this feature is lost on the sixth volution. The adult of C. tuberosum corresponds approximately to the seventh volution of C. adunsoni, but the correspondence is not exact, for at this stage C. adunsoni has not acquired a sub-sutural row of fine nodes, while its ribs have become even more spinose than those of C. tuberosum. C. adanso& is not to he regarded aa a descendant of G. tuberosum, but rather the two are desrended from a common Bncestor, C. adunsoni passing through its ancestral Atages rapidly and adding new characters, while C. tuberosum is rrtartled in its development and never attains the high degree of ornamentation rharac- terifltic of the adult C. adunsoni.

Cerithium echinatum I,om,ir(-A 1843. Cerflhfvm ~chfnatumLAMARCK. Anlmnux snm pert.. ed. 11. 1X. 201. 1887. Cerfthfum echlnatunt Tn~oxv,hlanrinl of Conch.. IX. 123. pl. 20. flp. 25-27. 1898. Cerlthium tchtnatitm KOIIELT,gnt. Conrh.-Cnblnetvon Martlnl u. Chem- nltz, Bd. I. Abtb. 26. 100. pl. 20. flm. 5-8. 1m. Qovm~fnechhatum COBSMANN.Essnls de PnlQronrh.. VT1, 69.

Mmsi:Rnfnns : Length. 49.4 nim. ; pre:itrst dlnmeter, 27.3 mrn. : nplcal nngle to the nlnth volutlon. 48". rlianplng to 37.5": sutoml nngle. 82.6". Omm : GrnylRh whlte. Rometlrnes marked nlth tranmerae pntctwn of brown. whlh 1s deepest on the spirals.

The protoconch of Cerithium echcmtum is much worn on the only available Rpecimen Rhowing that fratiirr, hut SO far as ran hr determined, it is precifiely like that of C. adunsoni. and the fht four volutions are indistinguishable nn the two shells. On the fifth volution there is lee contrast between the primary spirals and those of higher order than on 20 .49:\.ILS SBlV YOHK .ICAUEYY OP SCIENCES

C. adansoni. In other wordu, the primary spirals are not 60 highly developed, and spirals of higher order are coarser. This difference persists throughout the remainder of the shell growth. On the sixth volution, beyond the protoconch, the upper of the two primary spirals becomes more prominent. This tendency increases until, on the body volution, the ribs have become contracted into spines, of which the uppebprimary spiral forms the most projecting portion. The spirals of higher order increase rapidly in number until they become so crowded that they coalesce, fol'ming broad, flattened ridgea which are in places finely striated, indicating the orignal spirals of which they are composed. On the body whorl the uppermost spiral breaks up into fine nodes, and just before the end of this volution three spirals on the shoulder become similarly no- do%. On the lower slope of the volution there are also three strong spirals which become nodose toward the end of the whorl. Spines are absent from the under side of the body volution, as in C. adaptso&. The aperture Is hroadly oval. The inner lip bean a strong callus, with a well-developed tooth forming, with the outer lip, a short canal at the posterior portion of the aperture. The anterior canal is short and slightly curved. The outer lip is flarjag, its margin being crenulated by the spirals of the outer eurface. The lower margin of the outer lip grows more rapidlv than the upper, forming a projection somewhat as in Cerithium LiibPromm, hut not so strongly developed &B in the latter species. There is considerable difference in the degree to which this featiire is developed on several individuals of C. cchinatum.

IIORJLON ANI) IOCAI.ITY : Ilecent. Zanzlbnr. So. 401x1. ~oliinihln1:nlrerdty collectlon.

REMARKS : ThiA shell bears a drong resemblance to C. adansoni, but differ8 in the coalcscencr nf the fine spirals, which on G. adunsoni remain distinct throughniit thr life of the ehell, covering all the coamer features with finr thrratl-like lines. On 6. echinatum also nodes are developed to n lew dpprcr. apprariy only on the IateRt portion of the body volution. The more rapid growth of the lower portion of the outer lip on C. echina- turn i~ an important distinguishing feature, Rime it does not OCCTI~on C.adansoni. (1. echinahrm ao Rhown IIVitR early development, is closely related to C. tuberosum. hut it iR a more accelerated shell, since it loses the vertical elemmt from its outlinc nri the sixth volution, instead of the tenth, a8 in C. tubpromm. n'hilr more nccelerated than C. tuberosum. it is marc retarded than C. a/lnn,soni, Rince it dm not acquire nodes until near the end nf its life histo? WOOD, I'HYLOQENY OP CEIZTAIN CERITHIID& 21

Cerithium menkci Deshayes

Plate VII, figs. 2, 3; plate VIII, fig. 3; plate ix, fig. 2. istFi ('cri/hium trrarr/,ei Ussiiayes. Jioll. Rtunloii, p. 97. yl. 9. Ug. 15. I,%i. C'witltirirrr colurrtrra TH~N,Jlanual of Conch.. IX, 123, p1. 20, Ug. 19. lsw C'eriflrirc~rr mertkei KOUELT,Sytit. Conrh.-Cablyet voii Jlartlul u. Chem- nit% Ikl. I. Abth. 26, 208, pl. 37. Ug. 1.

.\IeAsLkt~IENm: Length, Y! uu.; greatest dlameter. 16.5 ~UJ.; aplcal angle to the eighth volution, 47, rbanglog to 36" ; sutural angle, 566'. ('oiue : I'iilfomilp crearuilolorect, or owaslouslly liavlng a few pale brownish qwtu scattered lrregulurly over the surface.

This shell is thin and delicately sculptured, with all the features of the surface ornamentation distinctly shown. The protoconch is not preserved, but the first volution remaining, which is probably the first beyond the protoconch, is ornamented by two spirals and faint ribs only. This volution has a diameter of .6 rm. On the next volution three fine spirals appear on the shoulder. Intercalated spirals are first developed on the third volution, and they Lnerease rapidly during subsequent growth until, on the body whorl, those of the fifth order may be counted. The two priniar, spirals remain of equal strength for eight volutions, but on the later volutions the lower spiral hecoiued weaker, until it is retluccd to thc size of' a secondary spiral, and the outline of the whorl is changed from an ol)tuse angle to approximately a right angle. At intervals on tlr~1;iter volirtion3 of the slirll one rib id slightly stronger than the others, and on the body whorl there IH one strong varir. A sub-sutural band, as in ('. luberosurn. ie developrd on the ninth and later volutions. Toward thc end of the body whorl this band becomes tuberculate, and on the lowcr slope of this whorl two strong spirals are developed. The aperture is elongate oval, witti a posterior tooth on the narrow c~llusof the inner lip. The outer lip is flaring, crenulated by the spiral3 of the outer surface. The antrinr ~811illis romporatively long.

I~onrzo~AND I.OCAI.ITY : Rerwt. 1ndl;iii OCWIII No. 20126. Columbln IJnlverrrlty collertlon.

I~MARKS: Cen'thium rnenkei diffen from (; cu~uItII1uI,, I.~VII,~~0 thinner shell, finer and more delicate sculpture, hroader ad1~9.9 widely ymed ribe. The development of the ornamentation of this Rhell IR so closelv par- fill~lto that of C. t?ihmo.wrn that. takm in twnncction with the siniilaritv in the form of body and aperture, it IcaveR no rnnm for dniiht that the 22 ~~Sw.~LsSBlY YORK ACAUBIIIY OF SCIBNCES two are developed from a common ancestor. This is clearly brought out by a comparison of the figures of young whorls on plate VII, figs. 2, 3, and plate III, fig. 4.

Ccrithium columna Sowerby

165. Cerithiunr colunitia SOWEBBY.Thesaurus Conch., 11, 855, pl. 178, Bga 55-58. Ifiwi. Ceritkiuni cvtrt?trrru I~EEVE,Conch. icon., SO. 2, pl. 1, 6g. 2. I&,7. Cwithiif/jt colztniita BYON ON, blanual of Conch., IX. 123, pl. 20, flgs. 17, 18. 18'~s.Ccrithiirm cdrtvinu KOBELT, Syst. Conch.-Cnblnet von blartlnl u. Chem- ultz, Ud. 1. .4btl1. 26. 8.5, p1. 16, Bgs. 7, 8.

SfsnsuxehcenTs : Imgth. Zj.2 rum. ; greatest diajneter, 17.1 mm. ; aplcal :iuple, 41' ; sutural :111;1e, 87". ('01~)~: (;rouiitl. n.liiie 01' wwni white, wlth Irregular patches of dark reddlsh brown, the amount of brown on different Indivlduals varying greatly.

The shell is thick and heavy, with relatively coarse spirals and narrow, sharp ribs. The youngest volut~onpreserved is 2 mm. in diameter. It bears two strong, equal spirals with intercalated spirals of two higher orders ilnd hespirals on the shoulder. All are crossed by ribs, which on the later volutions of the shell become narrow, with wide interspaces. The ornamentation retains the same character, with an increase in the number of intercalated spirals for the three succeeding volutions, after which the lower of the two primary spirals becomes weaker, changing the outline of the volution, as described above, from an obtuse angle to a right angle. Variers occur on the later whorls to the number of about two to the volution. The spirillfi become closely crowded just below the suture, and there iH a tcndency toward the formation of a sub-sutural band, but it never beconies well drveloped. On the later portion of the body volution small nodes arc dcrrlopetl on the stronger spirals. The aperture is hroadlv oval, with a welldeveloped posterior tooth and short, oblique anterior (.anal. The callus of the inner lip is thick and rather narrow. The outvr lip iH flaring and crenulated.

lloninm A311 I1lI'Al inrh It~.c.cwf. lndlan Ocean. Japan, Oceanlca. So 20127. ('oltiiiihia I'nlrtw4ty collectJon.

~~h.ll.4HKs: 'lhls sprclc's is R near relative of c. menkei, differing th, c.llsradcrP cBniirnrretril ahtI\t. antl. like that spwies, reveals in it8 development its relationship to C. luheroosunz. Ccrithium citrinum Sowerby

C'cr'ithium citrivuitt Wwm~r,Thesaurus Conch., 11, 855, pI. 179, tlg. 66. le(tjCi. C'critRiui~rcitriiiuw ICEEVE,Cunch. Icon., No. 1, pl. 1, fig. 1. 181;. Cerithiunr cttrfnunt TB'~oN,Manual of Conch.. lX, 123, p1. 20. fig. 21. 1898. Cerithrum citrinum KOBELT,Syst. Conch.-Cabinet YOU Murtinl u. Chem- nitz, Bd. 1. Abth. 26, 110, p1. 22, flg. 23.

~~I~A~~IXEMENT~: Length, 30.5 mu.; greatest diameter, 113.5 urn. ; aplcal angle, 37" ; sutural angle. 8i". ('OWH: Crexu white, with streaks and patches oP pale browu.

'I'he youngest volution preserved on this shell IS 2 IUUI. IU diameter, and its ornamentation is similar to that of the fourth volution on C. n~enkez. It has two strong equal spirals, one intercalated spiral and five fine spirals on the shoulder. One spiral is on the lower slope of the whorl. The ribs on this species are broad and, for the first five volutions, broader than the spaces between them. The two primary spirals remain equal in strength for seven volutions, after which the lower spiral is weaker, but the outline of the volution never becomes sharply angular, as in the preceding species. The secondary spirals of the shoulder and the lower elope of the whorl become as strong a~ the primary ones, and the outline of the volution becomes regularly curved. Extremely fine spirals of higher order are rapidly introduced, while the priinary and secondary spirals are raised into ridges carrying the finer spirals with them, 60 that the whole surface appear8 to be covered with bundles of fine spirals having deep grooves between them. The ribs disappear on the body volution, with the exception of one strong varix on the side opposite the aperture, as is usual in shells of this group. Yodes are ahsent from the entire surface. The aperture is broadly oval. The callus of the inner lip is thick and narrow, with a prominent pnsterinr tooth. The anterior canal is long and the margin of the outer lip thick and crenulated.

I IORIZON AN11 I1lCAI.ITY : Recent. Bird 1!4:I11dS, kldfic OCean To. 20125 Coluiuhla I'nlyerslty collwtlon.

UEMARRS:Cerithiu7n ritrinum diffew from f' (o/urrln,L 11, m,,rc

Ccrithium citrinum mut. bicolor Ho?nbroti et Jacques

lW-18;,3.(‘wi//tiiii/i bii.olui lioMUBOR et JAW. Voyage IIU I’ok Sud., iJl. a, tigs. 14. 15. 1%~. (‘withilitti utti/iw lhwx .\l;inual of (‘onch.. 123, pl. 2. fig. 2. 18%. C‘tvi/hitttji vi/t i)i~ojiI

.\lsasr.mxExr& , Leiigth. 2j.i iuiu. ; greatest diameter. 16.3 uiu. ; uplcal nr~gir,go. ~I:III~III~ to :W VII rile kist three rolutions ; sutural nngle, 86’. COWS: ~~IIII~liite Ith p:rtches of :I slightly darker yellowlsh tone.

?‘he first two of the vulutions preserved are precisely siinilar to those of Cerithium citrinunr. On the third volution the ribs Income contracted, leaving broad interspaces, a8 in C. columna, but the spirals retain the characteristic developirient of C. citrinum-that is, bundles of spirals with deep grooves between them. This type of ornamentation is carried still farther on the mutation bidor, until, as early as the seventh volution, the intclrsl~:ic-c~sare smooth and ~iearljor quite as wide as the groups of spirals themselves. The upper of the two primary spirals become3 slightly stronger than the lower as early as the fourth volution, and the two rcjtain the saiiw rvliitivv strcqtli for sewn wlutions. ‘l’lie eighth volution attains the angular outline characteristic of C. r,olumnn. All the spirals of this form ore prominent and sharply defined, even niore so than on vit1it.r (’. (ilritrurir or (‘. cduiwia. On the Iiii~Iyvoliition all the strong spirals brcalc up into fine nodes. The aperture ifi hroadly oval, with ;1 posterior tooth and short, oldiquc anterior canal. ‘I’lie outer lip is strongly crenulated. The callus of the inner lip is Rtrong and not closely applied to the surfaw of the diell.

Ilonrmx AY~LOCALITY . Ikwnt. Plillfpphes, So. 2012). Coluriih1:i I’nlverslty collwtlon.

REMAIIKS: ThiR ~li~llha8 the promincwt ~houlderof C. rolltmna. while rcbtwining ttiv tliiri iliidl. fino s(,iilptiiril ;rid di~c~loprii~~ntof .rpir:ils (,liar- acteristic of C. citrinum. WOOD, PH YLOOBX Y OF CE'RII'A1.V CBI1lTEIIID& 25

The youngest volution preserved probably correspond8 with the fourth volution of C. nenkei, being 2 mm. in diameter. This volution has two strong, equal spirals and three intercalated ones. The shoulder has five and the lower slope of the whorl one addItIonal s~~iral.hbs are present to the number of eleven on this volution. The ornamentation resembles that of Cerithiiirn citrinum in being inade up of bundlea of fine spirals, but the depressions between the groups are less deeply carved than in that species. The two primary spirals remain equal for five volutions, after which the outline of the volution becomes angukdr, but not sliarply 60 as in C. menkei. On this shell, as usual in this group, it is the upper of the primary spirals which is most prominent. The ribs become weakei on the body volution and disappear on the later portion of it. On this portion of the shell, also, all tlie coarwr spirals break up into rows of small nodes. A large varix is present on the side of the body volution opposite the aperture. The aperture iR hroadly ova!, with :i wll-cieveloped posterior tooth, narrow callus and short antvrior (.iiii;iI. 'I'lic. tiliter tip is firwlv criwu- lated by the spirals of tlie outer surfacx] iiiid not flaring.

Iloiixzoa AND IXWAI ITY : l~ir~i~irt.1h)tIi I~IWP ;iiid Kobrlt report the locsllty of the spwlert nfi iiiil~iinirii. Tlic q1~~~4iir~irs111 t11e c-ollrrtlon of Columhla Unl- wrsltg referred to tliln spcrles :ir? froiir tlrr Hlrd Isl:i~id~.I'nc-IBr Orean. 90. 20130. (hluii~l~h('iilverslty rollectlori.

REMARKS:This little slirll is nc'arwt to f'. drinum. hiit it differs in its sinallrr Rizr. wliitci color. IWC iliv~~~l~~t ;ir11~1 wrfiwe ornariicnfntrori, tti(1 iiiorc' wnpilar oiitlini, of tIi(1 \~~Ir:~i~iri-iiiiil this short ;iiltmor c.:inal. From tlic mutation bidor, it dilTcJr.: in ciz(~and cwlor and in the less prominently drreloped shoulder.

Cerithium mediterraneum i,erirori h lM:\.('rrifhlrrni inrcfitm-rmcriiit IAMAIIII(. .\irliir:iii\: s:im vert.. IX. 313. 185.;. ('cri f It firm nmlil rrrniir irm Smv F iiii) 'l'lrc~n:~iiriis ( 'nnvh.. I I. H65. pl. 178. tlK. 50: pl. 101. figs. 128. 131.133. IHBR. Ccrfthdurn medflerranermi I~EVI.('~III~.II. Iivnlra, XV, Si) 53 1W7. Crrifkhtni rirpcsfllv TRYOK.~lirrriiiil #if ('onrh., IX, 126 [)I. 21. HK. tri.

.\ILARIXLMEXTS . I.ivigtli. 25 irrrri. , imvitrst d1:iiiirtrr. 12.4 iiiiii. ; ap1c:iI iiiiplr :RJ.H". c.Ii:inglng to 25" on tlir srwiitll viiliitliiil , ~11tilr:iIrlnglr. i7.8". COI~R: (hwiii \vlilte. iirottlrd wltli rtrr:rl~sof yc4low nr 1)rown. ('olor h;rnd* tisii:\lly p:ixsiiiE tr:\nwersrIy ;ICIW.R tlir q>lr:jIR. Imt wiien pnr:illel with thrtii wmmhg to nwiiliy the drliwssloris Iwtn twi tlir splr:iIs rntlirr tlirin tlirlr rrior~ rnnrer portinnu.

The youngrat vi~liitit~iilti,.-i.o \,..I I,- :I iiiiir in ~linirir-tc-r 'I'hls ~.,IIIII~,II 26 .4,~~.4~sJEW )01tfi -4CAL)EdlY OF SCIENCES

is ornamented by two atrong, equal spirals, with two finer spirals on the shoulder and all the spirals crossed by ribs. The succeeding volution has a fine spiral intercalated between each two of the three already existing, and more spirals are rapidly introduced on the later volutiom. The spirals on the adolescent and adult whorls of this shell are all flattened, their limits being defined only by the exceedingly fine grooves between them. The lower priiuarj spiral begins to decrease in strength on the sixth volution, and the seventh has a sharply angled outline. On this volution a row of fine nodes is formed just below the upper and above the lower suture. On the body volution the shoulder is lost, and the surface is ornamented by five or more row8 of low nodes. The aperture is oval. The callus of the inner lip is thick and has a strong posterior tooth. The outer lip is thick and smooth. The anterior canal is short and slightly bent backward.

IJOHIXON AND U)CAIJTY . I

l{r:v.iiiKs 1 ~w~/tiut/~rudt/rrrurtcur/i lias its nearest relative in C. cilrt nuia inut. bitolor. It d~ffersin having flattened spirals not grouped in trundles, as in the latter species. On the whorls having an angular outline the reduced primary spiral becomes so much flattened that the outline of the lower as well as the upper slope of the volution is nearly a straight line. In the preceding species, which are similar to C. me&- /rrruii~uin.the Iouu prriiiar! SlJIrijl IP iilwii\< stronger and easily distin- guiShalJk from the wcondary ones. From C'. cdumna this species differs in h:ising finvr surfiwt ~lrnanit~ntilti~~ii,with flattenrd fipirals and broader ribs and in tlie los~of the shoiilder on the body volution. The last five fipecies and one variety, namely, C. mcnkei, C. cohmna, ('. ri/rinutrt and its mutation bic-olur. ('. srabridurn, ('. mediterrancum, constitute a group of closely related forms. They are evidently all developed from a common ancestor and for the early portion of their life history follow the same path of development. The divergence observed in the neanic and ephellic Etages of growth are all due to differences in the degrcc of cle~~clopmentor in the grouping of the varioua features of the surface ornament. In I'. rnenkei the development of the ~piralsand the sharply anglrd oiitlinc~of the whorls are emphaflized; in C. columna tlie development of the dioulder and of the ribs are distinctive, and in c. cil~in~mand its variety the grouping of the RpiralR in clunters is no- tlcml)le. They might all he rrgarded as varieties of one species, a8 sug- ppsted by Tryon, or thrir divergence in the adult stage might be consl&rd pat enoiiph rntitlt them to rank s distinct species. The latter method seems to the writer best to represent the degree of development which these shells have reached.

Cerithium dialeucum Philippi 161. Ceritkiurti diuleuciiirr I'winP& Abbllduiigen, 111, 14, pl. 1, Bg. 5. ~hWj.('wif/tiu/it diulcrccuat REEVE,Conch. Iconlca, SV, No. 18. 1SXi. ('et'if/tiuat diulCUCit//l TBrorv. hlallual of Conch., lx, INU).pl. 23, figs. 87. 88. ih!~i. C'e/.cthiu,il diuleucum KotreLr, Syst. ('ouvh.-Cablnet von Martlnl u. Chem- nltz, Bd. 1, Abth. 26, 167, yl. 31, flge. 8, 9.

.\IEASCKEMERTG: Leiigth, 31.4 UUI.; grrutest diuieter, 15 LUN.; uplcal angle, 4~".chuiigiiig to 25.2" 011 the lust two volutlurrs; sutural angle, 59'. I'OLOB: Grayish white ou the spirals wlth :ilternatlng ban& of dark reddleb ur purldisli browu in the grooves ktnren the spirals. The youngest volution preserved is 1.5 mm. in dameter, but it reveals nothing of the development at this stage, for the ornamentation is nearly obliterated on the first three volutions. The third volution, however, indicates the presence of two strong spirals crossed by ribs. The fourth volution has an oblique-angled outline formed by two primary spirals aiid three intercalated onw Spirals of the first, second and third orders are present on the shoulder and all are crossed by prominent ribs, with \Brice8 tu the uiiinlt1,r of abuut three 011 a voliitinn. The different orders of spirals on this shell are clearly indicated by a marked difference in, size. The two primary spirals remain of equal strength for about six volutions, after which the lower becomes somewhat weaker and one of the spirals on the shoiildrr 1wc.omc.s stroiigvr, so that on the httwo volutions the shell has thrw Ptrong qirals, of which the median one is the most prominent, and intercalatcd fipiralv to the fourth order are aleo Ilrcwiit. 'J'h whorl* of tlw ncarirc. sIit4l iirc roirncled in outline, and only the later portion of the body volution IJ(?'Om?Ysomewhat angular. The lower Jope of the hody whorl haw RIX or inore strong spirals with intercalatcd'oncs, all of which tcntl to hecwinc nodose toward the end of the whorl. The aperture is oval. 'I'he ~all~ia4,f thv inner lip is narrow, with a Imminent posterior tooth. T11r entcrior csnal is oblique and of moder- ate length. The intwinr of thc m1vr lip ifi deeply grooved to correspond with the ~piralsof thr outer wrfaw The grooves of this surface are white like the ~piral~,and the Ildgw arr colored to correRpond with the hprrssions of thr oiitrr siirfei~. .I narrnw margin of the outer lip is thick. smnoth and whitr.

I~oRIkON AKD 11)TAi.lTY 111~.t-1tI i'l~lll~~~)llirn.

yo 20132. Coliirnhln [yuiwrsity I ollwtlon. 28 ‘4h’h’AlA A‘BIV I’OllK ACADEMY OF SCIE’NCES REMARKS:l‘llis shell is distinguished from aii membera of the Ceh- thium colvmna group IJ! the strong and regular variation in the width of the spirals to correspond with their order of introduction. The regular banding in color is also a distinguishing feature. The general form of the shell, its earl! developlent and the form of the aperture all jridicatv its relationship to the C. tuberosum group.

Centhiurn album !loiribron rt Joiqircs

]%A:! I%-,:{. f’rr///////m /i//,/ii/t IiohlllKUN et .IACI&. \U,Vage I’Uk Sud.. \’, 101. 111. ?% figs. 2.3. IYS: f’,,jrr//d/rl,l ((,//ir,rl/~l~,’I’ICSON. ~1:111u:ilof (‘oiii~li.. IX. 1%. pl. 20. Bg. 26. In!tn. (‘O,.I//II~IIII (I Lr~~~r/ltnlI{OIIEI.T. syrt. ~‘u~~~~lt.-~.’~l~li~etvon Ilartlnl u. Chem- nit%. Iki. I. Abtb. 26. 102.

>I~.,,sI I

;III~~(~.52 ,-,O, ~11:111ging:ibrtiptIy to 23” 011 t11e I;wt two volutlons ; wtural angle.

L. ,~l..i0. (‘UUJB \VIllte or (.renu) wlilte I\ ith oc~c~;c~ioii:ilstreitkfi of dark brow.

Youngest volution, 3 inin. in diameter, bearing the two strong spirals always found in the young stages of this group, with three intrrcalated spirals. Fine additional spirals are present on the shoulder and the loper slopes of the whorl. The ribs are numerous and nearly as wide as the spaces between them. Fine spirals are rapidly introduced, becoming so crowded below the suture that they form a broad sub-sutural band which, unlike that of Ccrithiurn tubcrosum, retains the slope of the remainder of the shoulder. On the fifth volution preservrd, which is probably the ninth of a complete shell, this Rub-sutural band breaks up into a row of ~rnallnodes, and the ribs hrrorne ill-denfincd, giving place to a row of strong nodes on the upper of the two prirnarv spirals. The angle of the shoulder, except in the youngest stages, is very wide, and on the body volution it disappears altogether, being replaced by strongly nodose spirals, of which there are five on this volution with fine rows of nodes between them. The aperture is oval, with a well-developed posterior tooth and short. llhlique anterior canal. l’hr outer lip is strongly flutrd, anti the callus of the inner lip is narrow.

11flR170N ARI) IAM’AI.ITI Ilr. f-1~1 Ihhvr’m Inlni~d l’ii<.lflc ()

HEMAHKS:This epecier has hen considered nyllorlylltoll~lvIttI ~’snth turn cchinaturn, hut it diffvrii from the latter species in fieveral important rrspcc’ts. Beyond the young Ptaps, the ehoulder of (7. album iR never well defined, and the neanic whorls lack altogether the strongly spinose character of C. echimlum at the same age. The apical angle of C. album 1s much wider, and the abrupt change in the slope of the sides on the last two volutions is not found on C. echimtum. The youngest stages of this shell are closely similar to those of the species already described, but in the adult the ornamentation develops rows of small nodes instead of the diuu1dt.r angle present on many species of the group.

Cerithium graciliforrnc Sonserby

IXM.('crrtkrrrw !/roc.i/iforwe Sowe~sr.apnd I~EEYII.Conch. Iconlcri. XV. No. 49. Isxi. ('(~rrthiirnrc4urrrctrni '~'HYOR.Maiiiiiil of I'onc.11.. 111. 129, pl. 22, Bg. i7. Is!N ('c.ritliiuiir groci/ifrm,rc KULIEI.T.Swt. ('oiic+~.-Cablnet VOII Jlartlnl u. ('heriiriltz, Ud. 1. Ahtli. 3;. 124. pl. 21. flg 9.

>ILAPVREMENTY : I~iigtli.24.2 iiiiri. : yrcvitrst cliaiiieter, 0.7 riiri~.; nplcul angle, :i%:io,chiigiiig or1 the iiiiitli volutioii III 3;"; sntriral augle, R6.i". ('oim~ \Vlilte alth oi~c~:irluii:ilqwts IJP pile Iirown.

The youngest volution presrrrrd is .5 mm. in diameter, but it is too much corroded to show its form. Thp next volution is also much worn, but shows that it has two equal spirals crossed by ribs. On the third volution the fiame type of ornamentation continues, with three fine spirah on the shoulder. A single spiral i.c intercalated between the two primary ones on the fourth volution, and tlierr are four fine spiral8 on the shoulder and one on the lo\rc*r shiw of thr whorl. On the fifth volution, three rarices are developed, while the ribs hvtwen them become much narrower. Varices continue to he formed throiighorit the life of the shell and constitute a striking featir?~of its ornammt. 'The shoulder becomes nearly nt~snl~te.and the rilis l)renli up into ni~ilwuntil, on the tenth volution, the surface is marked by a strone varix and four row8 of nodes, of which the eecond below the Ruture ifi weakrr than the others. This type of ornamentation continues for the remaining thrw vohitions. The aperture i8 hroadly oral. .A pnsterior tooth ia present, hut in nnt drongly tlerrloped. Thc 1,alIiis of thv inner lip is thin, and the outrr lip is nearlv fimooth The canal iH qhnrt arid @lightlyreflexed at the margin.

111mr7n~ASI) 1111 AI IT) I~W~III T~II.I,~~.;II!~.V of thlw spwle~IR not glwn in ,,II? of Ilw decrrlptlons of it rIi;1i h;iw 111v~iipnhlldied, and the Fpecliiirn In the Colurnhin I'nlrersitp rnllwtii~ii IB :ilw unlnheled. Sn. 20134. Cnliinihln Cnlrerslty roliwtlnn.

REMARKS: This species resenittles rnmt closely L'crtthttrm c61~rrir10n dnd is considered onlv a vsrirtv of that fipecies I,! Tryon; bijt it diffrrs in its rnorp ~I~ndrrforin. iwsrI~,JmIvtr htioiildvr 2nd in thr grmt tlcwl- 30 .1".4L8 !lk,.\$' )ONK \('il~k;lf\~OI.' S('IE\'C'ES opment of varices. It differs also in color, being nearly white. The few pale brown spots are visible only with a lens.

b. American Species

Cerithium eburneum BricguitTre

1792. Caritltiurrr c,brcr,rc'vnr I$HI (~~'I&HE,Hlst. Nat. des Vers, Encyclop. Method., 1. pt. 2. 433. 1&9i. rrrithf~c?)~c.hvrneani 'I'RYON. B1:lnu:Il of Conch.. 1% Im, p1. 22. flg. i5. iH!)s. ('e,.ii/tfrnr ebrrr,rc,rcnr I

~ILA~CI~EMENT~~.I~igtli, 25.7 om. : prwteat dI:iiiieter, I1 nini. : apfcal angle, 3'.ch:~i~~lng to 2j.5' 011 the iiiiifli volutioii : sutural angle. 85.5'. Comrr: Wpte, Irregiii;irly iu:irkrd wlth patches of color whlch vary from golden brown to dark rcddlsh brown. The youngest volution preserved, which is probably the first beyond the protoconch, is .5 mm. in diameter. It has two equal spirals, which remain the only ornamentation of the shell for about one-fourth of a volution. IRSS accelerated individuals retain this ornamentation for a complete volution. The next features to appear are ribs and two fine spirals on the shoulder. Intercalated spirals are first introduced on the fourth of the solutions preserved, and the same type of ornamentation continurs, with the addition of hespiral8 for eight volutions. Beyond this the rib8 become ill defined and gradually break up into rows of nodes, which are drveloped on all the strong apirah until, on the volution before the lad, there are five such rowR. At about the ninth volution the lower of the tmo primary spirals hrcomes weaker, while the upper remain3 strong and defines a slight fihouldcr at about the middle of the volution. Yarices are irreplarly developrd with not more than two on a volution, and frequently lefis than two. The aperture is oval, and a posterior tooth ia well drveloprd The anterior canal is short and rather widely open. The outer lip is crrnll- leted, and the rallua of the inner lip is thick and narrow.

IInRrzox ANT)11)CAl.lTlER Itrcmt. West lndles. k<.lnrld;l So. 201.15. Cdiirnbln T'nI~(~rsltrcnllwtlon. .

REMARKB:The development of thi8 Rpecies and itr, gcnc-ral furnr art. 3q, closely similar to those of C~rifhiamtderosum as to leave little dou\)t of their degcent from a common ancestor, in spite of the fact that the two RhrIla come from such aidplv separated IocalitieR aa the West Tndies and the Red Sea. The Amrriran species of other gmrra, as well as Cerilhium, WOOD. I'HYLOGESY OF ('EIW,41.V CERITBIIDR 3 1 show such strong evidence of relationship with European forms that we must assume some at present unexplained means of intercommunication between species of the east and west shores of the Atlantic. This connection probably existed at 6ome earlier geological period, since Miocenic species show the 6ame similarity to European forms as do the recent species.

Centhiurn caudaturn So:, crby

IM5. Crrfthfum cotrdotunr SOWEBBY.Tliesaurus C0nc.h.. 11. 856. p1. 179. Bgs. 71, 72. 1868. Cer{thfffm caffdatffmREEVE, Cunc.11. Ivonlcs. XV. No. IG. 1898. CcrftAium coirdotttni KOBEI.T. Ryrt. Con~~li.-C;itilnet yon 3I:irtlnl 11. Chem- nlts. IM. I. Ahtb. 26. 112. pl. 2. Rg. 1.

MEASL~BEMENTY: I.engtIi. 31.5 iiiiri. : giwitvst d1:inieter. 11.2 mm.; :iplcal :iiigle, 41". ch:ingliig to 2!V on tlir 1:ist tliwr rolutlonP; sutur:il angle. i5". (XJI~.Golden tirowii. IAgIitrr In color. :it the npex and on the vurlres. Jlnrgln of the outer llp wlifte stre:iked wltli 1il;ic.k.

The apex of the shell is much corroded. The youngest volution to filiow the surface is 2 mm. in diameter, and has the ornamentation, characteristic of this group of ribs and two strong spirals. At this stage intercalated spirals are already introducrd between the two primary ones. and ~piralsof at least two orders are present on the shoultlrr and on the lower slope of the wlior). The surface ornamentation remains of the game type, with the introduction of more spirals, until the viglitli volo- tion, after ahich the rills Ileromcl cIisr.oritiniions and tlir stronpv spiral9 break up into nodes. On this voliition there is a ~uh-siitiiral row of nodefi, and each of the two primary fij)ir:iIF also forms a row of nodes. The outline of thr volution iR an ohtnsr anglv, with a slnpinp nr vnnv;iw upper surface and wrtical R~~PA.On tlir ninth vnlutinn prvsrrwl tlw fin& of the t3piraIP have Irecome ohsnI(~tc.a1111 hct\vrrn thc row nf nn(1os the fipirals arc compar~tiwlyfrar and ('oiirsr, with narrow intcrspiic,c.;. On the body volution thr nndra of the lnwr primarv +rill I)rromr \wrv si~~all,no largrr than thncr of tlw swmri(l;irv SpiwI!:. Th~awillition IIAL: on? rnw of strong nndr!: ---thnsrof thi. firct primarv qpir:il R row of riiI)- ciitii~lnodvs snmrwl~iitsn~all~r ant! thri~r~rinw of finv nr~il~iwci~iriil~. (111 the lower Rlnpe of the whnrl Ttw intcwnrdiatr spirals iirr c.rrniilstcd. but not dktinctlv nodose. The aperture k oval and thr (.alllt*: of thP innrr lip iR thin, with n wvll- developed pofiterior tnnth. The oiitrr lip ip didinrtly flaring and finelv crenulated along its outer marfin Thr antrrinr canal is Rhnrt and delyopen. 32 ,d.y.$.llas .\ t;\I’ ) OI

IjoR]ZoN AND LOCALITY : ihwit. Island of Gundelourie. NO. %13fJ, alulubla Ciiiwislty cokCtloD. The &ells of the Cerilhiunn tuberosum group, although differinggreatly in size, have a general similarity in form and in the essential characteristics of the aperture. Their variation is expressed most strongly in the features of the surface ornamentation. These features consist of spirals of the first and higher orders, ribs, nodes which may develop into spines, and a shoulder varyiDg in extent of development and in form. In order to bring out more clearly the relation between these shells as expressed in their surface ornamentation, they have been plotted in diagrammatic form, arbitrary signs being chosen to represent certain features of the ornamentation. On plate I the numbers at the left of the page indicate the volutions, the protoconch being numbered one. The protoconch, when present, is represented by a circle. The spirals are represented as horizontal lines, for while the! are actuafiy longitudinal elements, on the shell thev appear horizontal, and the diagram being intended merely to represent certain features in graphic form, It retains the line most readily awoeiated in the mind with what is seen on the shell. For a similar reason ribs are represented as rertical lines. Secondary spirals and those of higher order are represented by two horizontal lines. Nodes are indi- catrd I)\. dnts, and the outline of the volution is represented hv the lines which would be used in drawing its two upper slopea-that iR, an obtuse angle changing to a right angle to agrrr with the development of certain shclls. The diagram is intended to represent resemblances and differ- mw in ii pc~ner:iI \vny nnlv. It rrcwrds the introduction of spirals, ribs and nodeP. hut does not attempt to shorn the different kinds and depw nf cIc\~doprnrntwhich thev attain or siirh features RR size, degrw of rm- hracing nf the whorls, etcetera. More cnmplete details are given in the dcscriptinns and figures of the different species. The diac.rarn hringa out the fart that fiomr aprries are more retarded than others: for euamplr. prrifhiiim mPnliPi iR a mnrr rrtarded shell than p. nhsoni. AR shown hv the fad that on thr former apeciea the change

III IIw oiitlinv d>f 11w $\!l:)rl I~OPP not 1:rkv ph~rinfil thp ninth vo]1ltjon, and ndm arc. not aqiiired iintil the lad volntion, while hoth thae chanp ocuir much carlivr rm P. adnn.soni. A Fjmilar CompariRon has nlrradv hren madr hdiwrn I‘ h,hcmsvm and P. ndansoni. The diaeram fihow diffrrmtial sccelrration and retardation of re- htPd sppcies as in p. cchin(ifllm and C.gradiforme. On the fomer the ohli(ilie-an”Frdniitlinp is htnn thc wvrnth voliition. while retained until the tmth on the latter. Sodcfi arr, however, acquired on the ninth volutinn of f‘. grmiliformp and do not appear until the twelfth volution of IYOOD, l’HYLOOE1‘Y 01.’ CEICTd1.V CEk1~’1iLlL)& 3 3

C. echinatum. As compared with C. graciliforme, therefore, C. echinutum is accelerated in the acquisition of the sharply angled outline of the volution, but retarded in the development of nodes. A marked similarity in the early development of these species is well illustrated by the diagram. If a card be placed over the lower part of it the eye is at once struck by the uniformity of the figures; moving the card downward, differences begin to appear, becoming wider as repre- sentations of the adult stages are reached. The divergence would be even more marked if all the features of the shell could be indicated, instead of the mere presence or absence of the five features represented.

2. Genera and Species of Recent Shells closely related to the Ceritliium tuberosum Group

Genus Vulgocerithium Cossmonn

lWi. BulgorrrlfhfrrmCDBBMANN Essais de I’nlbconcb. Comp.. \’I 1. 75

Genotype Cerithium vu.Igatum 13nrai~iEn~;: This genus is closely related to (‘critliium sene. str. The early stages of the genotype Cerilhium v~ilgatumare clo~elysimilar to those of C. /r/hrro.sum. The atlult differs in a niimlwr of rather constant fratures and therefore may he considered di~tinct. The surface ornamentation of the adult fihell is>characteriacd In thc clrvelopment of rihs or large nodes, a auh-sutural row of ~mallernodes, and by the coaleficence of the fine spirals into flattened bands defined hv extremely narrow proovm. The margin of the anterior canal iR ii~iiallyslightlv reflexed. 11. CIosRmann’R main poinh of difference from Csrithium wna. atr. are not only tho elongate form of the shell and characteristic surface oma- mcnt. hiit csperiallv the form of the apertiire. The abRenre of the more rapid prowth on the anterior part of thc outrr lip, which forms a projecting tooth in Fnme specie3 of Prrithium. iR considered of most importance. and the ahnrter siphnnal ranal and Icas flaring outer lip are also mentioned.

Vulgocerithium vulgatum HI t~~iir,’r~

1137 I.r fivrrmh AI)ANNOY. Iilstolrv S;tt~~r~lledu S(mPp:tl, 1757 1, lncl pi 10, flu. 3. 17!12. f’r-rithiaiii r-rrl~~rrttrmliiciw~~iitii~., ~)h~thnaIrc=. No. I.?. IXX. f’wilhfrm ~rtlonluni RIWICRII~.Thrs:iliriis (’onrh , 11. Sfi.# 1’1 IiS, nr: 43; pl. 179. flg. 67. I VN f’o~ilhiirw vttlgnltrni KonF.1 r S? st (’or1c.h. .Tnhlnet Ton Mafllnl u Chem. nltx. Rd. I. Ahth. 26. RS. p1 IS AFR. 1-8: pl. 18. flp. 14. I!“lfi l’f!/gfiwvI/hirit~r’rrlf/attrrrl (’ttsn~i~~N.E‘.s~nls de Palbronrh Con)l), VII. . -- 6 I. 34 A~~ALS.~~lv YOHK ACADE'UY OF SCIENCES

Jj~B~~ME~T8:Le~q$h. 12.7 UJUI. ; greatest diameter. 21.4 WIl. ; liPfCU1 angle, 26.5'. changi~lgto 23" on the twelfth volutiou ; sutural angle, 88". Bnckgrourld bluish white, ruarlied by numerous si)lml bands of reddish bro\\.n, ahivh vu the young shell is deeiJest In the groove8 betffeen the but on the later and adult whorls Irregular patches of cdor cover most of the surfnce.

The only specimen etuhed which retains the protoconch is somewhat worn at the apex, but the protoconch appears to be like that of Cedhiurn adansoni. The second and third volutions are so similar as to be well illustrated by the drawings of these two whorls on C. adansoni (plate 111, figs. 3, 4), but the shell at this age is about twice the size of C. adansoni .at the same age. The fourth volution is like that of C. adansoni, except that about every third rib is much larger, forming a strong varix. These varices occur at gradually wider intervals up to the eleventh volution, when they disappear from the specimen described. The presence o$ varices is a variable feature, since in a series of specimens otherwise aim- ilar the varices are more prominent and persist for a longer time on some speeimens than on others. Except for the presence of varicee, the surface ornamentation is like that of Cerithium tuherosum to the seventh volution, when small nodes appear on the sub-sutural band, one at the end of each rib. Beginning u-ith the ninth volution, the lower of the two primary spirals becomes gradually less prominent and the ribs become less 0 well marked, until on the twelfth volution the uPP er of the two primary spirals only is prominent, forming a row of nodes slightly above the middle of the volution. The ribs, a8 such, have disappeared, being replaced by the two rows of node8. Spirals of serondary and higher orders increase rapidly in number, and on the later whorls the finest spirals become confluent, producing broad, flattenrd banda, with extremelv narrow depressions hetween them. On the bodv volution below the lower row of strong nodes from three to five large spirals are faintlv nodose. The aperture is elongate oval, with a distinct but not very prominent tooth defining the poderior canal. The oiitrr lip iR elightly flaring and Rhowe faint crrnulatinns. Thr calliiR of the innrr lip is thin. The anterior canal is wide and .ihort, with its margin slightly reflexrd.

Iloirimn ARII IIM AI r.irvh I{awrI >lwllterr:~wr!rlSm. n-rst roast of Afrlm. arid southward ttr Svne.yr:iI so. 2nl37. ~olllnll~l~lI'III~ rr.ll$ ~UllPrtI,,Il

IhfARKs: Tndiriduah of this Fpwien var! pt,~llrwt,n~ ltr[t,,. wl&h the apical angle. in thp strPn:

Vulgoccrithium breve sp nov

~~EASUBEMENT~: Length, 34.1 mm. : greatest diameter, 15 mm. ; aplcal angle, 43". changlng to 25.5" on the last two volutloiis ; sutural angle, 76.2'. C~LOB:Graylsh whlte, mottled with dark brown. Bands of dark brown occupy the depresslons between the spirals.

The apex of this shell is much worn. The youngest volution to show the surface ornamentation is 2 mm. in diameter and has the two strong spirals, as in the young of V.vulgatum. At this stage intercalated spirals arc! present, both between the primary spirals, on the shoulder and on the lower slopes of the volutions. On the sixth volution of those preserved the ribs become especially prominefit at the level of the upper primary spiral, and a sub-sutural row of nodes is also developed. On the whorl before the last the center of the rih becomes very prominent, and on its lower slope the spirals have a tendency to coalesce and become flattened, but this tendency is never carried very far on this fipecies. On the body volution the ribs become weaker and the sub-sutilral row of nodes stronger, until the two are of about equal strength. The aperture is broadlv oval, and thr c-alliis of the innrr lip is thin, with a prominent p~sterio~tooth. The outer lip is slightlv flaring and faintly crenulated. The anterior canal is short, with its margin slightly re- curved.

IIORIZON AND ILWAl.ITY : Ikrent. The ~~J~~~lll~~l~~111 the COllWtlOn Of a)lUm- Ma I:nlverrrity were rollwted by D. hf, Ritikrj- In dwp water OR the mo~ithof Grand Rlrer, northwest Msurltlus. NO. 201,%. Columbla Unlvers1t.v c*ollwtlou

REMARKS: The species is distinguished from 1/u/yutrrtlhfum i:u/pturn it8 fihortrr form, wider apiral ariple arid heavier and in~irr~)rorninc~~t nodrs, which make the outline of the volutions sharply angular. The fihell is also thicker and the spirals are more rounded than is usual with V.uulgatum. 36 A,%.\ 1I.H \/:I)' YOllK .1CADh'UY OF 6ClENCE6

Vulgocerithium plicatum Ph rlrpPi

1836. Ccfjt/iIflff, p/irUfu I'HJIJPPI. ihUU. h1011. SiCll.. p. 1%. 1887. C'erifhiuni cu/yufunr 'h~m,31:inual of Conch.. p. 126.

J~EASVRENEXTB: Ix~~gtIr. 25.1 IIIIIJ. : greatest dlnmeter. 1.4 mm.; aplcnl angle, 4"".cholrgiilg to 24O 011 the hst three volutlons; sutural angle, iso. c:o~urr,Ikickgrouud \t hire. tlikkly Ilrottled wlth yellow and golden brown.

?'he apex of the shell is much corroded, but a volution 1 mm. in diameter shows that It possesses ribs and two spirals. The fifth volution is the first to show the ornamentation plainly, and on this the spirals are broad, but not grcJatly flattened, and the oblique-angled outline is still retained. The embracing of the whorls is 60 great as to nearly cover the lower slope of the whorl. The succeeding volutions develop a sub-sutural row of nodes and the ribs are strongly defined. The upper primary Spirals remain alaa!r the mnre prominent, and the vertical element in the outline of the shell disappears at about the eighth volution. The adult ornamentation consists of strong ribs, whIch are most prominent at the level of the first primary spiral, and a sub-sutural row of nodes. The spirals are broad and Komewhat flattened, with narrow depressions between thrin. On th~hod? volution the ribs become narrow, crowded and SO low a~ to be nearly obsolete. The sub-Gutural row of nodes is here the most prominent feature of the ornamentation. The apertirrc is oval, and tho callus of the inner lip is thick, with a well-defined posterior tooth. The outer lip is thick and smooth, with an entire marg.in. The anterior canal is Rhort and widely open.

I~~IZONAND I~CAI.ITY: I{event. I~n~lltpunknown. So. 44,237. ~olui~il~l:~I'nlrersity dlwtlon.

Hr\r \IIKS' I'fi/~/f~f/,rr~//ii/i7~1p/i

~~t.~slil~AlKSTS: Lellgth. :w.8 ltllu. ; gretltest dlnnieter. 11 Ium. ; apkal angle, :

111lR170N AND IM'ALITY . k'lY'llt. ~All7l~~l.l'III~~III,WII So. 21)1.39. Colunihln 1:nlwrslty 1~ol11wtIim.

I~EMAI~E~: The Rpecies has hren rrfvrrrii I.'u/yoc.ertthiurr&vulyrhm, hiit it is distingiiished by its srnal1r.r rim. prynrtionallv rniirwr and rnorr roiind~~tspirals and h! ttw rnorr sliiirIiI\ p~)intcclforin of t11v main row of nodra. 'rhe spirals Bclow thv slight s\iouIdrr Iierornr rounded and irregularly nodose, inRtead of llattvnrd and iriconfil~ic.iir)it~,RR in 1'. iid- gatum.

The shell bear3 a close resrrnhlari~.t~tti the last spi~~esdiwrihrii~ hiit It (Iiffm in several important rrsprrta. The drvrlopment ia much more rrtarded thnn that of T-. /,li, otrrm CIIII-I. thr ~~~~~I~wI~IIITof thc 5pirals dow 38 d.1’SALS .TEW YOItK ACADEMY OP SCIENCES

not begin until the seventh volution, rn compared with the fourth volution on the preceding species. The embracing of the whorls is not so close as on V. plicatvrn. The adolescent and adult stages are distinguished by the much smaller nodes of the present species and by the form of the node, which is sharp and pointed at the apes in V. gracile, as compared aith the blunt but more prominent and more elongate nodes of V. plk tu.m. The anterior canal also differs in being longer, narrower and slightlv recurred. Vulgocerithium adenense Sout-rby

IXM. Cerilltiunt odrtresse SOBERBY.spud REEVE,Conch. Iconica, XV. No. ED. 18x7. Cerilltiirni odrnrnde THYON.Manual of Conch., IX, 124, PI. 20, Ug. 30. ItfiIH. (‘withiitni adrnenscj KOHELT,Syst. Conch.-Cablnet von Martlnl u. Chem- nlts. Bd. 1. Abth. 26, IN, pl. 39, fig. 12.

~JEAGUREMENTS: I,e.rigth. 3.2 UIIII. ; greatest diameter. 8.4 rnm. ; uplcal angle, X2.5”. cbanping to 21” 011 the last four volutions; sutural angle, 83.5”. C~L~R:Yellowish or grayish whfte, wlth illdeflned sluuous llnes of reddlsh broaii crosslug the 8ylr:ils.

‘rhe apex of the shell is broken away. The youngest volution studied is 1.4 mm. in diameter and has the usual two strong spirals, with one intrrcalated spiral and one or two spirals on the shoulder. Rell-drveloped ribs cross all the spiral*. The ornamentation remains of the same type, with the addition of spirals for the nest three volutions. On the fifth of the volutions preserved a sub-sutural row of irregular, low nodes is developed, and the iippw primary spiral forms Fharyointed node8 where c.rnssed tjy rilis. On the htrr rollitions the coarser spiral8 become hroad and flat. with fine proovc’s between thcm, and the finer Rpirals berome ohsolctc.. ‘I’hr adlilt ornamentation i8 that of widclg Rpacrd rih, which are almnr;t r;~i~nosvII(W crossed by the uppcr primary spiral. The upprr slopr of the rill is concave and the lower slope straight or slightly convex, which rives thp wntcxr of the rih thr appearancr of an upward-pointing, lllrint spine. ‘l’l~rr(har(1 tlirw row4 of finrlv nodose Rpirah on the lowrr slope of the hoily rollitinn. Thr apertiirr is rlongatr owl. The callw of the inner lip is moder- atcly thick. with a arll-drveloped posterior tooth, and the outer lip is thin. The anterior C~MI is Rhort and widelv open.

Ilonrzri.u ARI) IncAi.tTij.8 Iicrcrlt, I~li~ndof Rarak. PerRlHn Onif, Gulf of hdm. YO. ?f)14!), ~’O~llJ~~hkl[.111\?F%1!? dlprtlon.

8. PLEISTOCENIO tiPEClE9 OF VULQOCERITHIUM

Vulgocerithium vulgatum

11. Cossmann figureu, on plate 3, fig. 14, of his Essaie de PalCconcho- logie, a specimen from the Pleist.ocenic of Saix, which he refers to this speciw. It is smaller than the normal recent individuals, and the nodes of the principal row are prominent and somewhat widely spaced.

C. I'LIOCENIC YPECIEY OF CEBITHIUM

No specimens of the Cerithium tuberosum group from the Pliocenic of the Eastern Hemisphere are available for study, and the information furnished by the literature is meager. Ccritltium crenatunz BI~OCCI~I,figured in Quenstedt's Petrcfaktenkunde Deutachlands, plate 204, fig. 46, is of a small specimen from the Pliocehic of Asti, which may belong in this group. It has the oval aperture, poa- terior tooth, and crenulated outer lip of Cerithium gem. str. It also has in the young stages two row8 of nodes which are stronger than the othera, but in the absence of specimens it is impossible to be sure that it is correctly placed here. In the American Pliocenic several Npeciea occur which apparently belong in this group. Of theee only two actual specimens were obtainable, but good figures and descriptions aid in determining the relationaship of others. Ccrithium callisorna Doll

Plate 1111, fig. 1 ; plate ~111,figs. 1, 2; plate IX, fig. 1 lNI2 Crrifhlirni colliwnio DALL Tr;iiiR. Wagner Free InRtItute of Srl., 111. pt 2. 282, pl. 14. flg.'8. 't

.\IKASI.REMENTR : Imgtli. 20.8 iiiiii , grmtrst cllnmeter, 8 rnm. ; nplrnl angle, :{5". dinnging to 26" on the kist tliw voliition~;fiuturnl angle, 80".

The poungeat volntion pre~rrvrdnn thr Aptximen8 stiidird is .4 mm. in diameter and hae three spiral^, nf which the two lowrr are eqiial in FIT and stronger than thc upprr onr. Rih are alfio present at this st;igi 40 AX:\.ILS 5E14 YOlUi ACADEUY OF SCIENCEX On the fourth of the volutions preserved one spiral is intercalated between each pair of primaries and the upper primary spiral becomes weaker, making the shoulder more pronounced. The sixth volution has three fine spirals intercalated between the two strong primary ones, with one above and one I~lowthe third primary spirai. The lower slope of the vohtion has at this stage two spirals, one stronger than the other. ’ik same type of ornamentation peI’616tS throughout !he growth of the .AeIl, with an increase in the number of spirals, which vary in strength according to the order of t)ie,r iutroductjon. TII~third primary sprai on the shoulder remains always stronger than any secondary spiral, IJUt not HO strong as tlie other two primaries. The latter become very yrorninent and produce the well-defined oblique-angled outline of tlie voliition so characteristic of C’crilhiunt tuberosum. The aperture has the uslial oral form of the shells of this prOlllJ. uith a narrow, thick callus and prominent posterior tooth. The anterior canal is short and widely open.

HIIIU~NASIJ IAN AI.ITY l’Ii~i~ei~l~*of the C:ilwsshiiLchle Ma, Florld:i, so. 1256!), Allll?ri4~:lll MUSl~UUl c~ollec~tloll.

Ik,fARKs : The first three volutions preserved on this shell rerall the sc~vcqith.eightti ;riiil tiinth voliiticins of tli~I.h.~~nt(. +IK?(~IIJS. (‘rri//iiuni returdalum (plate IV, fig, 10; plate v, fig. 9). On the 1att.c.r shell thee spirals are developed, the two lower of which are stronger than !he upper, and the first intercalated spiral appears hetwecn the strong sprrals. A similar drvelopment is seen on C. cnl2isom.n. but it is more acccleratrd than (’. rc/arrlofi/rn,pincr it8 ~11~1uIeIrriR distinguisliahle from the first, while C. retardatum never acquires a distinct shoulder, but rrtains the primitive rounded outline of it8 volutions throughout life. C. cnlliwma is most rloselv related to the recent fiprcies (’. fubrrosuni. Itlit it is inorv priiiiifiw thn thc lattw ,~pvws.~inw it rrtajns th~oItIiqiip- angled outfine of thr roliitIons throughout life WithfJllt a trace of weakrn- tng of tlw Iowrr spiral, while on C. lubrronm thr lower primary spiral becomes gradually lrss pminrnt, r~ntilon the hod? volution thr oittlinr Is sharply angular. Thr resemblancr of the adult C. ra2lisom.a to thr ping C. tiibcrosiim IP mnrf Ptriking, and if the lattpr spcri(As werp froln

a IIW di~tantIoc.alit\. up illrelit st on1.e’ assiirn(’ it to lw tllr Plioc.rnlc, ancestor of C. tubrronrm. As it iP. wr mag Riippose that (‘. ia//i.soinn ;* the Amrrican represrntatlrc. of this ancwtor. which exiatrd in thr vlcinity of the Red Spa nr thr 1ndi;in Orran. hilt has not rrt hwn recnrdrcl from that localitr. 41

Cerithium floridanum Morch

Itliti. C'errrhiutrr ffuridanunr 3loRcij. .\I:I~;Icw~o~~~IUiiitter. XXIII, 114. IWL. Cerifhiiini puridutrunt I)ALL 'I~IIIS.\\':i;.ner Free Institute ol Scl.. I'hlla., 111. IJt. 2, DW.. 282. Id. 14, fig. 10.

MLASUHEMYNTY: L~gtl~.34.2 IIIIII. . grv:itc*'st di:iii~eter,I4 IIIUJ. ; al~l~ilangle. YJ". cl~aiigliigto 22' 011 the t\\t.lftli 101u1itm ; sutural angle, 86".

The protoconch of the speci~iienstudied is much worn, but is apparently of the same form as that of ('erithiurn ahansoni. The succeeding three volutions are too much worn to show the ornamentation. Tlie first volution on which surface features appear distinctly is the fifth, wliicli has a diameter of 1.9 mm. It bears ribs and two strong spirals. The shoulder is long and has three fine spiralu, with a sub-sutural band composed of two elevated spirals A single spiral is intercalated between the two stroiig onvr, arid the Io\w SIII~01 lire \elution is very short. 'I'lie earlier whorls of the shell bear an irregular number of varices averaging about two or three on a volution. On the sixth and seventh volutions the sub-sutural band gradually IJrvalis iip 111111 ;I row of nodes and the spirals become larger, but do not increase rapidly in number. On the eighth and ninth volutions the larger spirals becorne nodose where crossed by the ribs, and 011 the next rollition the nodes n1' tliv sul~-siitural row and those of the first primary spiral become larger than the others and of equal strength. At the same time the nocIc!s of the second primary spiral become weaker. On the two mweding volutions the large nodes just bvln\v the suture and those of tlitt lIp[JlT ~riiriiiryrpiral arc in line verti- cally, forming distinct ribs. mhrlr the. nibs of the lower primarv spiral are Rrnall and twice afi niimeriiu~a$ thow of the upper row. 'I'hc fipirals on both the shoulder and lower slopes nf the whorl alternate in strength according to their ordrr of introdiictioii ;iiiiI are strongly dcfinetl hy thr deep, narrow grooves between tlie~ri. On tlir tliirtwnth ant1 last volution the nodm of the loner primary spiral l~cwrncwry srnall and niirnerous-- a mere line of heading around the slid1

The body volirtion and the apertiirc. aria inii~hIirokcq I~rtthe. iniirr lip IA prefierved, Rhowing that it has ;I thick callir~with n blunt postchr tnoth, and the anterior canal is short ;lid rather tvidelv op(w.

F~oRIZoN AN11 IOfAI IT11 ti ~'~1~1~~~~111~l~;il~~~i~:l~l:lt~~~l~~~ tWIx ;Illti O%ltry! ~1;lii atrr Cmnty. Florlda. So. 12568. Ain~rli.:in MIISCIIIII,Y~IW.IIWI

I~MARKR:7'hr adult ornanimtatitm of thrri little stwll sl~tm- *~itiw variation from thc fiprc pirrrr 11.v Dall [Is$?. plate 13, fig. 101 ia thv 12 ANBALO .IEW IOBK ACADEMY OF SCIENCE8 marked difference in the strength of the subordmate spirals and in the more angular outline of the adult volutions, but the shell agrees with the description and figure in essential respects. Its early development and the general character of its adult features show it to belong undoubtedly to the Cerithium tuberosum group.

Cerithium glaphyrca Dall

1892. Cerithium glaplytca DALL,Trane. Wiigner Free lnstltute of Scl., Phlla., 111, IJt. 2, p. 283, PI. 14, fig. 4. MEASU~EMENTB(DalJ) : Length. 16 mm. ; greatest dfameter, 6 mm. ; REMAIZ- mu MUBUBEMENTB FWM FIOCBE: Apical angle, 2%'; sutural angle, 88'.

No specimen of this species has been obtainable, but from the original description and figure the following features of interest in this connection may be determined. From the figure it appears that the shell has two spirals stronger than the others, with fine spirals between the two primary ones and on the shoulder. A third'strong spiral on the shoulder becomes nodose, but is not so strong as the two main spirals. All the spirals are crossed by numerous closely set ribs. The two strong spirals remain of equal strength and continue to form an oblique angle for the whorl until the body volution is reached, when the lower of the two becomea weaker. The aperture is of the type wual in the Cerithium tuberosum group, with a narrow callus and strong posterior tooth, flaring, crenulated outer lip and short anterior canal.

11oRlZr)x AND IOOTAI.ITT: I'IIOI~CIIIC of the (':ilousnlintchle Ma. Florlda.

REMARKS: This species has a strong fundamental resemblance to Ceri- .!hiurn callisoma in the form of the body and of the aperture, and in the persistence of the oblique-angled outline of the whorls formed by two strong spirals with a weaker one on the shoulder. The most striking difference is in thr very numerous ribs of C. glaphyren, which are so closely 8et afi to Rppear like rows of nodes where crossed by the coarser spirals. C. glapkyrea appearfi to have the essential characteristics of the C. tuber- mum group, but prohahly represents a lateral branch from the main line, expresfilng its divergence in the development of numerous ribs.

Cerithium glaphyrea milt. litharium Dall iX!C!. I'~.rtfhlrrmnlnphi/wtr v:ir. lifhnrirtm DALI,Trans. Wagner Free InntlNte of Pvl.. 1'lllI:l.. I 11. pt. 2. pl. 11. Ag. 9.

>l~.~htIILMLRTS i1hIl I lmxlh. I9 mnl. : Crentest dlanwter. 6.5 mm. WOOD, PHYLOOEN Y OP CEllTdlN CEl117'HIlDR 43

The mutation Zithurium evidently belongs to the same phyletic seria 8s the species to which it is related, differing only in minor features of the ornamentation, such as more prominent nodes and additional rows of fine beading. Cerithium algicola ADAMBand C. musearum SAY,from the character of their apertures and the general appearance of the shells, seem to be related to this group, but in the absence of specimens and with very im- yerkvt figures, it is impossible to be certain of their position.

D. MIOCEXIC BPECIEB

1. Cerithium.

So far as can be determined from the literature, the Miocenic of the Eastern Hemisphere furnishes few specimens of the Cerithiurn tuberomn group. This is due doubtless to lack of preservation, rather than to a paucity of species existing during that period. ('rrilhium bronni PAIITSCII.of the Iliocenic of the Vienna Basin, may possibly belong here. [See HORNESand PARTBCH,1856, plate 42, figs. 12a, b.] The figure, which gives no clue to the ornamentation of the young shell, is imuBcient evidence for placing the shell definitely, but the aperture corresponds with that of C. tuberosurn, and the ornamentation of the adult is similar in type to thnt of other species of Cen'thiurn sens. str. An unnamed variety of C. crenatum BROCCHIis mentioned by HOENES and PARTSCHJ1856, p. 4091 as occurring in the Miocenic of the Vienna Basin. Accorjing to tlirir figure# [lor. fit.. plate 42, figs. 13, 141, the hell hathe ~dultcharacteristics of this group, but the features of the yoiing shell cannot be determined from the figures. Cerithium mediterraneum, described with recent speciea of Cerithium, iR recorded by HORNERand PARTRCH 11856, p. 3931 from the Miocenic of the Vienna Basin.

Cerithium calculosum Hoslrrot

iVP5. f'rrflhiwii rn/r.tr/onwn RARiTmin. .\lPni ~601. Rur les rovlnms dc Ror- deaua. p. M, pl. 3, flg. 5.

JleifitxnimTR: I,cv~gtli. tl.3 11~111, grr;itest dlarnetcr. 14 1 IUU. ; 11plca1 iinclr. 3i.2" : wtur:il an&. 79.3".

The protoconch iR absent froill thin shell, but the youngest volution prrwrred is prohahlv the fird heyond the protoconch, and it is 1 mm. in diameter. This voliition iR ornamented hv ribs and two equal RpiralR. 44 AX?:Y.~LSSEIY IOR~~ACBDEJ~~’ OP SCIENCES

The second volution is like the first, except that it has a third weaker spiral just below the suture and numerous ribs are present at this stage. On the sixth volutlo~lof those preserved tlie sub-sutural spiral beconies nearly a8 strong as the two primary spirals, and all three become strongly nodose where crossed by the ribs. On the next two volutions the shoulder practically disappears, and the volution seem to be ornamented by three rows of strong nodes with intercalated spirals between them. Varices are irregularl! tle~eliiljc~j!‘rim the fifth volution onward aid on the latrr whorls become estreiiiel! prominent, forming a conspicuous feature of the ornamentation. Both ribs and varicea are set at an angle with the vertical axis of the shell, go that thej appear to twist in passing from whorl to whorl. On the tenth volution of those present tlie two lower spiral^ again I~~iiinemore prominent than the sub-sutural row, giving an oblique- angled outline to the volution, which has vertical sides and a row of strong nodes on the shoulder. Jhther coafse intercalated spirals corer all tlie surface between the rows of nodes. Just above the suture a row of fine nodes is partially concealid by the succeeding whorl. On t.he body volution the shoulder is nearly ohsolete, and there are six rows of nodes, of which the t%o upper are the strongest. A very ttrong varix is prcsent on the aide opposite the outer lip. The apertnre is elongate oval, with a narrow, thick callus and well-developed posterior tooth. The outer lip in some individuals is extremely thick, and the aperturr in these specinwns IS soiiwwhat constrirtcd I)? tlir addition of material to the inner margin. Other specimens do not $how such thickening of the lip. The Riphonal canal is short and slightly reflexed at the margin. At an earlier stage of growth the canal was Imt toward the left, but the animal has abandoned thiR position and continued the canal in a downward direction, the earlier growth being left as u curious knoh on the outside of the tube.

IlanmN ANn IXWAI.ITT’ ~~ltrenlc.hlnrtlllar nrnr Bordrat~x. To. 2f11-i1. Cot ti 111 bki 1.nf rrrsitv collwtlon.

RElfARKs: This ~pccieshxars a Rtriking refiemblanre to the Florida splkries, C. glaphlyrro. in tlw clnsrly set rih. the numhrr of tllr spirals and the form of the aprrturr; hut it differs in being a more closely roiled form and in haring niimrroii~very Rtrong varicrfi. This species ha8 hrcn madr the type of a new genus, Chondrocerithium,. the diRtingui AhinFr charactrrktics lieing the prefience of a polumnellar plication and #light diffrrmcrn in thc aperture. The development of the RPccieR fihon-9 it8 cloar rrlationahip to Cwithium. and the aperture does not differ in anp MRPntial rrsprrt from many species of that genus. A faint 1VOOD. PI1 YLOUE 1 1 OF CEltT,llX CERlTiiiiD& 45

trace of columnellar plication was found on only one of the seven specimens studied, and this barely distinguishable feature seems insufficient ground for the establishment of a new genus.

Cerithiurn calculosum, inut globulus n. rnut

Like Cerithium ylaphyreu, C. calculosurn has a variety which differs from the type in having finely nodose spirals intercalated between @e stronger ones and in having the row of fine nodes just above the suture fully exposed rather than covered by the next whorl, as in the case of the original species.

Ito8rzolu AND IMAI.ITY : Mlawtir. M:tr~ill:i~~ttenr Bordeaux. So 2001.12. Cdunibls 1,’nireraltg (.oiiw~tioii.

Cerithium chipolanum Do11

1X!12. f’rrithiuui dripolorrirwi DAII.. Tr:iiis. \V:igiwr Free Institute ol &I., Phila.. 111. pt. 2. 2K5. pi. 22, flg. 7.

.\IEAGI.REJIERTA (1):iil) : Lenatli. 10 iiiiti. : gre:ltrst diameter. 4.5 min.

A specimen of this species has not Ixen obtainable, but a good figure and description make posRihltr the determination of ita relationship with a fair degree of prohability. The author of the species describes four spirals on each volution, and the figurca shmw that in the young shell two of these are more proiiiinmt than thc othrrs. forming the oblique-angled outline of the whorl characteristic of the Ccrithiurn tubcrosunz group. Later in the growth of the shell the lower of the two Rtrong spirals becomes weaker, giving a Rharply anglpd oiitline to the whorl. On the body whorl two of the Rpirah on the dioulder increase in size, RO that the ornamentation of this volution consistfi of a shoulder with two strong spirals on its slope and two helow the shoulder angle. The aperture is of thr typr iisnal in this group, with a well-developed posterior tooth and short, widely open anterior canal.

HORJZOR AND IDCAIJTY : 01ikr Mlwwlc II~the Chlpla be&. northwest Florida.

REAIARKB: nail state8 that (’ I hip/,mtm 18 not closely related to anv of hi8 preceding speck, which would include 0. cal1isom.u and C. gln- phyreu, but he doe8 not sav in what respect the divergence is expressed, iinlew the high development of variceq mentioned iR considred surh ri dif- ferenre. Varices are. hoaeser. charartrrktic features of Clerith&m senR. str. This little species is more clofielv coiJed than the Pliocenie C. miti- 46 AENAL.6 NEW' YORK ACAD.E&Y OP J'CIE?fCES soma or the recent C. tuberosum and resembles in that respect C.culansoni. It may be the American representative of the Miocenic ancestor of the latter speciee rather than a member of the direct line toward C. tuberosum. 2. Vulgocerithium

Specimens of Vulgocerithium vulgatum are reported by Hornes and Partsch [1866, p. 3881 from the Miocenic of Italy and the Vienna Basin. The species seem to persist through the Miocenic and Pliocenic to recent time. Homw and Partsch describe several other species which are evidently closely related to V. vulgatum.

Vulgoccrithiurn rninutum Serres

This species is recorded by Homes and Partsch [1856, p. 3901 from the Miocenic of the Vienna Basin. Specimens have been obtained from the upper Oligocenic of Saucats, and the species is descrihed with others from that horizon. The Oligocenic specimens differ from the figures of Homes and Partsch [1856, plate 41, figs. 8, 91 in their smaller size and the lees prominent nodes of the median row.

Vulgocerithium zelcbori 1fornt.s and P ortsilz IKM. Cerffhluni zeleborl HOBNEEfind PABTSCH.Abhnnd der k. k. geol. Relch- snnstnlt, 111, 301, PI. 41, fig. 10. This species seem to be closely related to V. minuturn. differing in the more rounded nodes. less continuous rihs and the greater distinctness of the sub-sutural row of nodes. The young stages are not descrihed in detail. and the figures are not flufiriently enlarged to shorn thrm clcarlv, hut the general form, aprrture and aiirfacr ornamentation are Po similar to those of V.vulgatum that they mav he referred to the Kame group with a high degree of probahility.

Vulgocerithiurn doliolurn Rrorclic

1814. Crrtthtwrn Rvltolwn RROTCHI.Conchlologlo fosdle nuhappen.. 11. 42. pi. 9. fig. 10. 1856. Cerftblrrm dolldam A~~RNFRnnd PABTRCH,Abhnnd. der k. k. grol. Relcb- snn~talt.Ill, 392. pl. 41. flp. 11.

Hiirnes and Partsch record this species from the Miocenic of Italy and the Vienna Basin. It has a somewhat Rhorter spire than most species of Vulgocedhivm. hilt it iR similar to shells of thie group in the cllaracter WOOD, PH YLOOE'S Y OF CE'ILTAIX CEII1THIII)P 47

of the ornamentation and the form of the aperture. The nodes of the sub-sutural row and of the first priinary spiral have a somewhat more rounded form than most species of the piius, and rows of fine nodes are intercalated between them. A variety represented by fig. 12a, b, has the high spire characteristic of the typical Vulgacerithium.

Vulgocerithiurn rubiginosum Eirhwald IqW.Carithiurn rubryfnosuni EICHWALD.Suturb. Sklzze von Llthauen, Vol- hynlen u. 8. w., p. TU. 18.56. Cerithiuni rubiginovuni HOENEBand PABTSCH.Abhand. der k. k. geol. Relchsanshlt, 111, 3%. p1. 41. figs. 1G. IS.

So far a~ can be learned from the descriptions and figures, this little species has all the characteristics of Vulgocerithium. It differs from the last species in the absence of the intercnlated rows of fine beading, and the nodes are somewhat more prominent. The species is recorded by Hornes and Partsch from the Miocenic of the Vienna RaRin.

E. OLIGOCENIC ASD EOCENIC SPECIES 1. Cerithium

The relationship h(~tuerntlic Oligwcnic and Eocenic sp(~cirsIS so (.Insi~ that it has been thought hest to consider them together, taking up the forme in the phylogenetic rather than the stratigraphic ordrr.

Cerithiurn aquispirale 511 nov

Plate 11. fig. 6;plate v, fig^. 3, d ; plate VI, fig. 3.

.\(mwBEMENni (List flrr rolntlon8) . lmgtli. 23 inin. ; greetent dlnrneter. 10.1 nini. : nplr:il :iiigle, R:KI~.cli:inpliip to 2li.H" on tlie last three VoliitloiiR; sutor;il angle. K5". .

The general fonn of thtR shell is high and narrow, with moderatrly embracing whorls and hit dightly imprwed fiiiturcs. The apex of the shcll iR broken away, ilnd the earliest vdii~ionprrserved hiis x diarnrtrr of 4 mm. and height of 1.1 mrn. On thi~roliition. two spirah are stronpcr than the others and are equal in strength. A third primary spiral at the base of the mhorl iR partly covered hy the succeeding volution. Between the etronger primary Rpiralfi a secondary and two tertiary ones appear, and one primary, with fniir secondary fipirals, iR above the Rhoulder angle. ThiR volution hear3 clrrcn dronp. roundrd ribs, whirh are wrll 18 ..IXX.~LSJBH’ l’offh iC.~liEN1. OF SCIENCES

developed fro111 suture 10 suiuru. ‘I’he hi. fourth and eighth ribs are mud1 stronger tlian tile otl~cr’s.forriling vanccs. On the later volutions, these varices appear at irregular and less frequent intervals, having in the adult from five to ten ribs between the varices. On the succeeding volutions more spirals appear, until those of the fifth order may be counted. These are very fine, but still preserve their rounded character, and several of equal strength are crowded between the coarser spirals. The strong shoulder and the two equal primary spirals persist until the body volution is reached. On the latter volution the primary spiral on the shoulder becomes as strong as the primary ones below it, and the shoulder, which is still present on the preceding volution, disappears. The body volution bears below the three primary spirals already mentioned three more strong SpirdlS, with finer ones between them. Here, too, the ribs become weaker, the spirals stronger, and at the crossing of the two there is a tendency t.0 form nodes, though the development does not go far enough to form actual nodee. On the later portion of the body whorl the sub-sutural spiral becomes as fitrong as the two primary ones. The aperture of the shell is oval, with fihort, reflexed anterior canal. A well-defined posterior canal is also present, the inner margin of which is bounded by a ridge, hut not a distinct tooth, such afi appears in Cerithium lubrrrmm. The inner lip is cotwcd IN n narrnw c-allns, and the oiitrr lip is lightly flaring and notrhed to rorrrspond with the strong spirals of the exterior surface.

II~~ILIZIISARI) II)CAI.ITY ’ Tlir ~irwlsrIiorlmn of ttilR fipwlen I8 not known, but It WIS hind In :I cvllrc*tlon of iinldeiitlfled ~lirll~from the Ewenlc of the hrls R:isln. So IW?X (’oli~nit~l:~I‘nlrersltg collrc~tlon.

J~FVIIIKS. ~’~ri/h~umm,wi.cpir(iJp lins n ,.low rclcrmhlanc~rin form and in thr fratiirri: of thr aperture to P. lnmellos~m.but it diffem from that eprcies in thr charactrr of the Kpirals, wliicli are Rtrongly developed and haw a roiinrlrd fnrni instract of appraring like irnhriratinfi lamella, afi in the. lattrr sprcips. C. Inm.rl/oaum also diffrrs in the log8 of itR secondaq FpiralR on the adult whorls. (’. (r.yii.cpim/r hap thfi inn i.tron,n sp1r:jlv and the ~III~PPOURfipiralR of hiehrr order characterictir of C. tiibPro.wm, and it retain8 these features thm~iphoiitlife. Thr bod\ vnliition hag rsprrially Rtrong spirals on ita Imcr clop(>.and fhc Iwcr part of tIw oiitcr lip prnwil a little more rapidly than thr npprr part. Thr prrpiRtsnre and drvrlopment of this tendencv wmld in timP prndiicr R ZtrnnF projrction of the lower Rpirals like that RPPn on thr aprrtiirr of f.frrhtrosi~m. At the same time the prominent IVOOD, PHYLOQESY OP CEItTAIiV CERITHIID~ 49 sub-sutural spiral on the later part of the body volution of C. cequispirde suggesta the Vulgocerithiumgroup. The species may well be a type from which the C. tuberasum group arose, but Vulgocerithium probably arose from the ancestor of C. aquispirule, C. cornuelk9runt. The young stages of C. cequispirulc are unfortunately missing, but the adult shell is so similar in general character to C. lamellosum that the young stages may also have been similar, although this is not certain to be true, for similarity in adults does not necessarily mean similarity in the young.

Cerithium lamellosum Bruguih

Plate III, figs. 7, 8 ; plate IV, fig. 8 ; plate v, fip. 7, 8 ; plate VI, fig. 6.

Ii!)?.Cerifhiuni la?/telZoeunr BBUQUI~RE,Encycl. Method., p. 488. 1824. ('erifhiitwt lamrlloaurit DEsanuEs, Dew. deu coqullles loss. des envlrone de Parh. p. 3i0, pl. 64,flp. 8. 9. ]%(XI. <'rrifhirtm lomelloeunt Deemuhs, Dew. des anlmaux sans Pert dhuverts dam le hassln de P:lrln. 111. 159. 1IwMi. I't~idtowrUkhn lamrllomtrn U)GBMASN.Essals de PalEoconch. Comp., VII, 81.

MEASIJREMERTB: Length. 48.4 mm.: greritest dlameter. 13.8 rum. ; aplcal Rnple. 3".ch:ing:ing to 18" on the elewnth volutlon : Ruturn1 angle, 84'.

The volutions of this species embrace but slightly, producing a long, slender shell. The general outline of the whorls is gently rounded, with lightly impressed sutures. The early stages of growth are best seen on n young individual of nine volution8. The beginning of the protoconch of thiR specimen is not preserved, but it seems to have compriwd about one and one-half volutions. Beyond thiA a Rpiral appears at about the middle of the whorl, the portion8 above and below the spiral becoming flattened until a distinct ~houlderis produced. On the fiecond volution beyond the protoconch the spiral has become elevated at regular intervals to form faint nodes, and on the third volution another spiral appears below the first, while the node3 are elongated into faint ribs. The Fecond Apiral soon bwomes a8 strong 8s the first, and the two form a slight projection aroiind the median portion of the whorl. The two equal spirals remain Rtronger than the others throughout the life of the animal, but the ghoul- der is never a conspicuous feature of the ornamentation. On the suc-' cceding volution, the fourth beyond the protoconch, there ig a faint constriction of the shell below the RutiirP, which, mith the ~utureitself, out- linr~an indiRtinct fipiral. The two voliitions which follow are like the 60 AXNALS NEW YORK ACADIMY OF SCIENCE8 fourth, with a gradual strengthening of the charactem already introduced. On the seventh volution faint secondary spirals are intercalated between the first two and on the shoulder above the first spiral. The ribs are well defined and extend from suture to suture, about one on each volution being enlarged to form a varix, a feature which persists on all the later whorls. The ninth volution differs only in having an additional faint spiral just below the sutural one. An adult individual shows twelve volutions, from which, as shown by comparison with the young, about four volutions in addition to the protoconch have been broken away. On the eleventh volution of this specimen the spirals are five in number, with ribs extending from suture to suture, and separated by interspaces slightly wider than themselves. Although the surface is much dissolved, faint traces of secondary and tertiary spirals may be seen. The strength of a11 the spirals varies considerably, not onlv with the condition of preservation, but in different individuals similarly preserved. Some individuals show the secondary and tertiary spirals distinctly, while they are hardly visible on others. The epirals of this species, especially on the later volutions, have their upper edge projecting sharply and their lower edge merging into the surface of the shell, RO that the whorls appear to be made up of overlapping lamells with their edges turned upward. On the later part of the body volution the spiral just below the suture ia broken up into nodea, and the thrw spirah hrlow the central hand become extremely strong. The aperture is oval, with a deep anterior canal and a well-defined postprior canal. The calhie of the inner lip is narrow hut romparativelv thick. The outer lip ia folded into a Rerim of prominent lohra. which correspond in povition with the spirah on the oiitde of the Rhell.

JIORIZON AND II)CAI.ITIER : (‘ok:~ireCrossler I [‘pper Eocwk ). ~II:IIISS.V:III~ Grlm~on.1’:irIs Ihslii. .So. 2011:%.~~oli~n~t~l:~ 1’nlrprslt.r rollr~tlon.

REJIARKR:This fiprries begin8 it8 life hietory in a miich simplrr manner than any of the Rprcis thu~far deficribed, and it is not until the Lijsth volution that it fullv acquires the shoulder, which in recent accrl- eratrd forms hrgins irnmcdiatelv aftrr the protoconch. The primitive @tapspreceding tlir formation of ribs, and with one volution only, have been crowded out of the ontogenv hi, acr~lerationin ~uchforms as Gem: 1hl:iim adansohi and C. tubero.wm. CPrithkm lnm.Pllo.wm, dora not continue its development in the clirec- tion of 0. tuhProsim for. after having acquired intrrcalatrd spirals of high ordrrs. it nearly nr quite lows them on the adolescent and adult WOOD, PIIYLOUESY OF CERTAIN C:EIIITHIIUrE 51

whorls, and the fofm of the spirals changes to the imbricated type de scribed above. On account of this divergence expressed in the adult shell, C. 1a.mellosum may be considered a lateral branch from the line developing in the direction of C. tuberosun. No descendants of C. lamellosum have been found in the material studied, and it may have died out at the end of the Eocenic without giving rise to later species. The young of C. lamellosum gives a clue to the kind of development which preceded the stage with ribs and two strong spirals, and it is to be expected that from such primitive conditions development would take place in several different directions. This we find to be the me, as illustrated by several of the following species. A!. Cossmann refers this species to Ptychocerithium on account of the narrow opening of the canal and the strong varix opposite the outer lip. He considers it aa closely related to Vulgoccritliium, but from the development of the early stages it seems to be more closely related to Cerithium than to either of these.

Cerithium inabsolutum Dcshayrs

IXHR. Ccrfthfrrm Itiobsolitlum DERHAYEE.1)eac. (leg :inliiisiix R:IIIR vert. d(.c.ou- vwt8 (hns Ie bnssln de Parls, 111. 170. ))I. 74. fig. 28. l!MHi. I'tUc.Ar,c.rt.ifkiifni ittothwtirtirni ('OSEMA SN. 1). HI).

\It;AHl,'ItEMENTH (JWUIlg Indlvlduill) : IX?llpIh. 10 111111. ; gre:IkSt dl:lilletW. 4 iiiiii. ; iipic-;il angle, 2:1.5" ; antural nngle. W'.

Two very small individuals probably represent the young of C. innbso- lutum, but are referred to that species with doulit, since no adult is available for comparison with them. A part of the protoconch is present on on(' specimen and, RO far ;IS can IK'determined, is like that of C. adansoni. The first complete volritinn is .3 mm. in diameter and bears two continrioiis spirnls, one of which appears slightly before the other. This tFpe of ornamentation continues fnr liix volutions, 1,111 on the Revcnth rihs iiro tl~~\~Iopeil,fine Ppirals allp'ilr on tlw shoulder and a spiral k intrrcxlstcd Iwtwwn the two primary spirals. Strong varices to the nhmber of one or two to the volution are developed on the remaining whorls. On the eighth volution a eonstric- tion below the suture defines a siih-sutural band which is raid into nodes where crossed hy thp rilq and niimeroi~~RpiralR of hiBhrr order are introduced. The shell comprises eleven volution~, nnd t.he two ctrnng, equal Rpirals characteristic of CeTithium remain undiminished in Strength on the last volution present. The lower dope of the bodv volutinn hear8 two st,rong ppirala with thrw fiwr ones helow them. 52 ANGALS NEW YOEK ACADEMY OF EClENCES The aperture ie oval, with a long columella and poorly formed siphonal canal. Xo callus is present on the inner lip, and the outer lip is too much broken to determine its character.

HOBIZONAND LOCALITY : Calcalre grossler. Qrlgnon. Par18 Bahn. KO. m, Museum of Comparative W~OATcollectlon. REMARXS:The absence of a callus on the inner lip and the poorly formed siphonal canal accompanying a surface ornamentation characteristic of young Crdhium seem to indicate that these specimens are young individuals. They are referred to (’. inabsolutvrn on account of the elon- gation of the lower part of the aperture and the character of the ornamentation, which seems to correspond with that described for the species. Whether or not the specific identification is comet, they belong undoubtedly to the genus Cerithium 6em. str.

Cerithium calcitrapoides Lumarck

IMH. Cwtfhiulji wl~~ifmpoidrxIAMABCK, Ann. du hlus. Nnt d’blst nnturelle de 1’:irIK. 111. 274. 1x24. f’rrifhiim mlrilmpotdes I)ESHAYES. Dew. des roqullles toss. des envl- roils de I’:rrls, Mi. pl. 40. 5gs. 18, 19. 23. IMN. Ilufilluriu cvlcifrupoldrY COBBUANN,Essah de Palbconcb. amp.. V11. 134.

>~EANUB~~.MENTS.l~iigtl~. M) ilini. ; greatest diameter, I8 mm. ; apical angle, 25” ; suturiil cirrgle. Xi”. The youngest volution studied has an ornamentation of one spiral only. 00 the next volntion a second spiral appears above the first, and on the fourth volution of those preserved, the two Apirals are crossed by ribs, but it is not until the fifth volution that the two spirals become equal in strength. At this stage the shell has the shoulder charactenhe of Cerithium. with two equal spirals crosfied by ribs. On the seventh volution a spiral ifi intercalated between the two primary spirals, and fine ones appear also on the shoulder and on the lower slope of the whorl. On the ninth volution the lower primary spiral hm become weaker than the upper, a tendency which increafirs until, on the twelfth and later volutiom, thr lower primary spiral is reduced to the size of the secondary meR, and the upper spiral form8 the projecting margin of a fiharplv angled volution. The apwtiirr i~ elonpatr oval, with B thick callus on the inner lip and hrt. widply open canal. Thr outer lip iR dightly crennlsted.

t~on17oN Am m-Ai.rrim Cnlcnlre prossler. Sable8 MoyenR. Grlgnon and iii;iriT other Jo(~R1irir~In tltr ElrIs RnPln. So %?X,Anirrlrnn \iiisrnm rollertlon. WOOD, PHYLOBHNY OF CERTAIN CERlTHllDI 53 HEUARKS: This speciw resembles C. Equispirale in the young but diverges from the type of development illustrated by that species in the adult. It may be considered a lateral branch from the main line of evolution of Cerithium.

Ccrithium bicarinaturn Deskayes

Plate 11, fig. 8.

IS#, ('crifhium bicarinaturn LhsiiauEs, Dew. des cugullles foss. deu envlrons de I'3riE. 1). %6, pl. 53, figs. 14, 15.

>leasuRemms: Leugtb, 24 IUU.; greatest dlalueter, 9.5 ulu. ; uplcal ttugle, :;t)' ; sutural migle, 85.5".

'rhe youngest volution preserved on the specimen described is .? mm. in diameter and is ornamented by two spirals, the lower of which is the stronger. Ribs are absent at this stage. The two succeeding volutions are like the first, except that the upper spiral becoms equal to the lower in strength. On the fourth of the volutions preserved ribs appear, and on the fifth a faint constriction below the suture defines a slight sub- sirturai band, which, however, lasts for only two volutions and is not seen on the adolescent and adult stages. The specimen thus far described is a young individual preserving only eight volutions, but the same type of ornamentation persists on full-grown qweimcns, the adult ornamentation !wing simply two strong spirals with a long shoulder slope, a concave wrfac~hetween the two spirals and a short lower slopr. The body volu- tjon has two spirals below the primary ones. The aperture is nearly circular, with a short siphonal canal so widely opm that its cross-section does not reprewnt a curve of more than 180" The callus of the inner lip is narrow and has a slight projection near the posterior end, although a distinct tooth is not formed. The outer lip is broken on all the specimens obtainable, but it waa evidently thin and, according to the figure of Deshayes, mas not crenulated.

HoRxzoN AND LOCALITIEE: gable6 Moyem (Upper Eocenic). ACY.~IIMultleu l~~i~irinnp other lo(-nlltles In the r:Irh 11:idii. So. 20144. Columbln Unlverslty (loIIrvtloti

REMARKS:The adult of this species corresponde in eaveutial character idim with the fifth volution of Cerithium EametEomn and with the Rec- md of G. udansoni, and although orcurring at a higher horizon than (' Inm~llosurn.it illustrates a rnorv primitive tvpe of development. It rrprefiente the persistence of a type of Rhrll which waR probably devel- 54 .4X.Ve41,S .$’h’IV I’OIM ACADEUY OF SClBiVCES

oped as far back in geologic time as the Triassic, since we have in Jurassic time a shell with rounded volutions and an ornament of three simple spirals, which wa6 probably developed from a two-spiraled form just as the mutation tri,s/iru/e, described below, arose from the type species by the developnient of another spiral on the shoulder.

Ccrirhium bicarinatum mut. trispirak n mu1

Plate 11, fig. 7.

IH24, f’crithi~ttj~/~IUJ~I~III~III~I I~ISHAYEIS, Drsi,. des c*wlullles fosw. des envlrons de 1’:Iris. 1). %(i. p1. 53. flg. 6. IWi(i. (‘f,rithi?c?ltbicurinufunt IksIjaYEn. Desc. des onini. H:IIM Wrt. dkouvertv d:iiis le basslri tle 1’:irIs. p. ]SO. ~IEA~CHEMENTS: lxiiptli. 25 iiini. : greatest diameter. 10.2 nini. ; uplcal angle. 25” : suturat :ingIr. W”. The developrnent of the variety is precisely the same as that of the type spwies to the seventh volution, on which a faint third spiral is introduced above the two primary ones. This spiral grows rapidly until it equals in strength the lower primary spiral. The median spiral is slightly stronger than the others, so that the outline of the volution would be a regular curve if represented by a line touching.the edga of the spirals. This type of ornamentation persists throughout the remainder of shell growth. The hdy voliition ha8 two etrong 6pirals and thrw or morcb fin(. ones I~rlowthe three prirnarv spirah. ‘I’he apcrture is likr that of the tvpr fiprcies.

Ilonr~o~ANI) INALITIPR ’ R:ihI(’R 1loyrnR I I’pprr Fdrcmlr I. Acy-en.3fultlen :ind othr IiwaIitm in ttir 1’:irIR H:isln. Xo. 2(11.15. ~‘o1mnl)l:if’nlvcwltg r~ollcvtlon. I~EMARKS:This mutation differs from tha type fipwirs only in the presence of a third ppiral, which hecomefl strong enough to change the outline of the volution. There is a perfect gradation hrtmeen the fipecies and it8 mutation, Fincr Fprrimens of the former we found in which the third fipiral is had! di~tingni~hableas a faint elevation on the adult whorls. and others in which thiR feature appears earlier and earlier in the ontogrnv until the typical form of the mutation iR developed. The mutation represrnts mvrrly the nrxt fitep in the evoliition of thifi group The early stages of this species are described from a young individual of ten volutions. The protoconch of this specimen is miming, but the \oungest volution preserved is .5 rmm. in diameter and is probably the first volution beyond the protoconch. It is ornamented by a single spiral only, and no ribs are prtsent. Aiiother qird is added above the first on the next volution, and on the third volution of those preserved, the two spirals become of nearly equal strength. Ribs first appear on the fourth volution anti on the fifth, a fine third spiral appears above the two primaries. The three spirals are well developed on the seventh volution, and on the eighth the first intercalated spiral is introduced between the two lower primary ones. Another intercalated spiral soon appears between the two upper primary spirals, and the adult whorls have one spiral intercalated between each pair of primaries, with two fine spirals above and two below the three primary spirals. The body volution has two strong and six very fine, closely set spirals on ita lower slope. The aperture is similar to that of C. bicarinutum, being nearly circular, with shallow anterior canal. The cellus of the inner lip is wider and the posterior ridge better developed than on C. bicarinatum. The outer lip is somewhat broken, but the lines of growth indicate that its lower margin grew more rnpidly than the upper one.

II~uizo~ANI) LOCALITIES : S:~bles!doyens I I'pper Eocenlc). Le Cu~$elle, Acy- eii~~~ultlen,Parls Bnsln. So. 20146, Columbln Unlverslty c~llwtlon.

tilrar~nKs: Ccrithium retardatum represents a step in advance of L'. /i I / orinlit urn mu t. t n'spiralc in the tlrvchpinrrit of intercalated qiira IN. I'lie thrw forine, C. bzcarinalim. its miitation, tri.vpira/(J,and f'. trlarrln- turn. constitute a direct series in evolution. C. bicarinatum ckwlops rilm and tan rqiial primary spiral8 nnlv. The niutation frirpiralr carries the development farther in the growth of a third primary spiral, and C. rcturdatum advances still farther in the introduction of intercalated 6pirals. P. retardatum illustrates the law of rtxapitulation, for its fifth volu- rim is like the adult of C. bicnrinatnn, and its seventh volution rcipro- -t.ntbG the adult of the miitation tr;.s/iro/v. At the sarnv tiriic the law of wcleration iA illustrated hy thk shell, since the evolution represented by ~JICentire life history of both C. hicnrinatiim and C. bicarinatum miit. Iri.+ro/r is pasect1 nwr in thr first sewn voliitionx of 1'. rrtardufum Rut while C. retardatum i~ acvrlrratrd RR compared with C. hirarinahm. 19 wtardcd as coinparril with t', n.yuis//irnlP and othrr fihrlls i~criirri~i: '11 the I'pper Eocenic. It map Ire compared with the IJpper Cretzic tl. '' n/hcn.w in the main linc tJf w~~lutinnof the C. tiib~rosungroiip. Cerithium sp. undt

MEA~UBEMENT~.Length, 13.5 WD. ; greatest diameter. 5.3 mm. ; aplCal angle. so,changfug to 26" on the last three volutlons ; sutural angle, 83.2'.

Two small specimens of nine volutions each are the only representa- tives of this species in the collections studied. They are probably young individuals, but it is impossible to identify young shells from the figures and descriptions as usually written. The youngest volution preserved is .4 mm. in diameter and has one spiral only. The next volution is too much worn to show the ornamentation, but the third volution has two spirals crossed by ribs. The two spirals become of equal strength and, with the ribs, remain the only ornamentation until the sixth volution, when a fine spiral is introduced below the lower spiral. On the nest volution a spiral is intercalated between the two primary ones, and on the eighth volution a fine spiral appears on the shoulder. The body volution retains the characteristic two strong spirals and has two fine spirals on the shoulder, with one intercalated between and one below the two primary spirals. The lower slope of the body volution has two strong spirals and several finer ones below the primary spirals. Spirals of the third order also appear on this lower slope. The aperture is circular, with a shallow anterior canal. The callus of the inner lip is comparatively wide and has a distinct ridge near its ps- terior end. The outer lip is thin and not crenulated on the voung shell.

Ho~izoxANO U)CAI.ITY : Eocenlc, I'nrlN R:i~ln. I'reclse horizon and locallty unknown. So. 20163. Columbia Unlverdty rollectlon.

REMAnKS: This little shell is like C. bicarinatum to the fiixth volution, after which it develops in a direction different from that of the two descendants of C. bicurimtum already described, namely, C. birwinatum mut. trispirde and C. retardatum. ThiR divergence is expressed in the acquisition of a third spiral on the lower dope of the whorl, inRtead of on the shoulder, RE in the line of evolution just described. The spirals of the shoulder slope are introduced later, but always remain fine, and the shoulder peni8tfl to the laRt volution prefient on thefie forms, while it is lost on (7. hiran'nntirm miit. trispiral~.. Thifi fiprrirs mav he conaid- ered a deficendant of C. birarin,nturn.hut it represents a different path of evolution from that, inchiding C. rdarddturn. WOOD. PHYLOQE3'II OF CEKTdlW CEZCITHIIIJB 57

2. Vicinocedhium

Vicinocerithium parallelurn gen. ct sp. IIOV

Plate VII, figs. .I, 5 : plate \ III, tip. 4, 5 : plate IS,figs. 3, 4.

BIEASUBEMENTB: Length. %! 1111~1.: prateat dlaitieter, 12 mm.; aplcal angle, 3U.5' ; sutural angle, 81.5".

The protoconch of this Epecjes IS not preserved. The youngest volution present bears three spirals, the lowest of which is the most prominent, and is separated by a wide interspace from the two upper spirals. On the next volution ribs appear, and the niedian spiral becomes stronger than the upper, but not quite 60 prominent as the lowest spiral. A slight ridge below the suture forms a fourth ill-defined spiral. On the third volution present the two lower spirals are equal in strength, and a fine spiral is intercalated between them. The third spiral ha3 also become stronger, 80 that the outline of the volution is a regular curve. Two additional fine spirals appear just below the suture. The fourth and fifth volutions are essentially like the third, with an increase in the number of fine spirals. On the sixth volution the median primary spiral bccomea stronger than the other two, and this tendency increases until, on the adult whorls, this spiral forms the margin of a sharply angled volution, with numerous fine spiralfi on the shoulder and the lower slope of the whorl. The uppermost primary spiral is reduced to the rank of a secondary spiral, and the lowest primary spiral, originally the strongest on the shell, is much reduced in relative size, though still stronger than the secondary spirah. This and another Rtrong spiral jwt above the fiuture are crenulated, showing a tendency toward the formation of nodes, which on the latest portion of the body volution are fairly well developed. A third nodose spiral iR present below those jtist described, and fine spirals are intercalated between all coarser onm on the lower slope of the body volution. The aperture is nearly circiilar mi the anterior canal is rather long and widely open. The outer hp Is thin arid the inner lip is covered bv a fitrong callus.

Iloerznn. AmIAN AI.ITY SatiIw My) CI,~ I c cidpellr. l'iirlr hnh No. Ml5R. Coliimhln I'nlvtwlty mAlrrtlc,8h

REMARKE: This 'species ha8 been considered identical with CC,~thiur~r ( I~kinoce1-iiliivm)howi ~ERII..and if thr adiilt characters alonv are imsidered, they are hardly tlistinL.iii.;lial,l(.. tlic only diffcwnce bring that the present species ha8 a snmrahat higher spirr and the shoulder iR far- AH 9SS.41-S SEW )‘ONK ACADEMY OF SCIENCE8

ther from the horizontal. The development of the two shells is quite different, and for this reason they should rank as at least distinct species. Bv coriil)ari~ipfigs. 1, 5 IJIi plate. \]I, -4, 5 on plate ~111,3, 4 on plate IY with figs. 6 on plate VII, 6 on plate VIII, 5, 6 on plate 19, it will be seen that V. paralleluni acquires its sharp shoulder by developing its median primary spiral and retaining the lowest primary spiral in a subordinate position, while 1’. bowi Oevelops its uppermost primary spiral to form the shoulder angle and the median spiral is rcduced to the rank of a secondary spiral, and is finally indistinguishable from them. The development of 1’. purdleluni and V. borret differs so widely from that of Cen’llrium that they should be referred to a distinct genus, as is here done. A full diagnosis of the genus awaits a more extended study of related species which should be included in the same genus. The two species are described here to illustrate the case of parallelism mentioned in the introduction.

Vicinocerithiurn bouei ( Deshuyrs)

I’late \II, fig, 6, plale v111, fig. 6; plate IY, figs. 5, 6

1x24, (‘(,ri?hirrrn botrri IktiIiA~~6. Iliw. den cc~~ulll(~sfons. des env!rons de I’aris. I I. 347, ],I. 52. figs. 9.11. I!MII;. IlU/r//urru botrc.1 (‘ORtiblAh’h’. ESS:IIR de ~’ak%WllCh. COInp., VII, 1%.

>IEASUREYENTG. 1,engtli. 22 IIIIII. ; greritest dlsrneter. 9.5 uirn. ; :iplcaI angle. ,I-, .,O ,. suturril :~iigle.81.5“.

A portion of the protoconch is preserved on one specimen. It is about .4 mm. in diameter and apparently has the form of the typical Cerithium protoconch. The next volution beyond the protoconch has apparently but one primary spiral, forming a slioulder angle just above the suture. The third voliition has niore fine spiral8 on the shoulder, and both rib8 and intercalated spirals appear for the fint time on the fifth volution. On the sixth voliition two of the primary fipiralfi above the ~piralof the slioulh angk I)trwmc>~trcinper, until on the Ruccreding volution all three are of cyial strmpth, making the outline of the voliition an obtuse angle ’with filoping upper Furface and verticd sides. On the next two volutions the uppermost of thc thrre primary spirals hrcomes etronger, until it form8 thr margin of an rxceedinglg sharp shoulder angle. Later the median Rpiral brcomrs rediiced to the size of a wcondary spiral, the lowest prirnaw ppiral hrcomrs irrrgiilarly undulating, and another undulating *pirill of somewhat IPSH fitrrnflh is developed jiifit ahove the suture. Thrrhangm pr~diircin thr adiilt fitage a volution that is almost indis- tirigiiishahlr from that of I’ porullelum. 1VOOU. PuYL0UB.V Y OF CERTAIN CE111TBIIU& 59 The aperture of this species ie like that of 1'. parallelum, except that the canal is somewhat shorter.

11OHIZON AND LOCALITIES. S;lbiW >IOJI?ilN. Le (;U@Ellf? and UIL!~~localltle5 iii the I'arls Basin. SO. 2vl(jo, Coluuibla I'ulverslty cvllectlon.

1hiAulis: C'. bouez IS referred IJ.Y .\I. ('ossmann to the genus Natillu- rul, but a comparison with the type of that genus, B. zonale, shows a wide difference in development, the latter species resembling Cen'thium in its early stages. As will be seen by comparing fig. 6, plate VII, with figs. 2, 3, 4, plate 111. L'. bouei differs from ('rrithiunt from the protoconch stage onward, and this difference entitles it to rank ae a distinct genus, as noted above. 3. Polamides

Genus Potamides Brongnrart

1810. I'ofoniida BROMNIABT,Ann. du Mus. Sat. d'hlst naturelle, XV, 44%. 1#2',. f'ofuwidus UBONONIART.In Cuvler's Itecherches 8ur le8 ofisemens fossllw. 11. 1!Hni. I'OfU/,rldCY CO68MANN. hH:IIR dI? ~'ilI"of'0llCh. ~hllp.,VII, 103.

Genotype Potamides lamarcki BROSONIART. The genus Potamides is distinguished from Cerithium mainly in the tilight development of the siphonal canal. In the type of the genus P. lamarcki this canal is short, widely open, and with its anterior margin slightly reflexed. ?'his type of canal persists with little change from the middle Eocenic to recent time. r. I lie ciarly st;igw of /'o!./imidf,.c,;is 1liliiiti''l iiiit in cmnwtion wi11i tho description of the genotype, are closely Rirnilar to those of typical ('eri- ih.ium, but after having developed the Crnlkium-like outline of the volution with two equal spiral8 crossed by rib, Ppecies of the genus continue 111 emphasize the formation of nodss as thcir most characteristic ~urfac~? f~,iitiiro.instcad of acwntinp thc~sliritls. i~.- III ('~rifhium.In this paper only those species are included in the genus Potmides whicili have not

lmlp an aperture similar to the genot,vpr, hut also have yourig fitages indicating a similar path of tlc~rc~lri~iiric~iit. ('rrithium and Potamirlrs are a.it!iout doubt cl~tiely rt-latrd pvlirra, nrid Potamides is thv rnorr prirnitirr in Rtriicture. The aperture of the \(liing Potamiden is alrnnst dcstitritc. of canal. while the aperture of the \winF C~rithi~mis likr that of I'olnrnid~s.and it is reamnahle to siippose 11!;1t thr order of (wdiifirm has twn from fnrmR without canal to those 60 ANhfALs .y,y1+f FORK ACADEMY OF SCIENCE8 with the &ght canal of Potamides, and later to the well-developed canal of Cerithium. Hence the ancestor from which both genera are derived must haye been more like Potamides than like Cerithium, although the type of Potamdes, P. lamrcki, and other species of the genus occur at hjglier horizons than many well-developed species of Cedhium. They represent the persistence of a primitive type of structure throughout il long period of geologic time, while Cen'thium, though descended from a common ancestor, represents a more rapid evolution of highly specialized forms. Potamides lamarcki Bwngniurt

1810. Potauiidrs laarorclii BRONGNIAET,Ann. du MUY.Sat. d'hlst naturelle. xv, 468. 111. 22. flg. 5. 1~24./'rrifhhm t,rict-oxfr,n,u DESHAYES.Dew. des tuqullles foss. des euvlrons de I'arls. 11. 412. pl. 5!k Ugs. 32-34 I%~;I;. ('c~rrfltirctrrlumu~lii I~SIJAYES. 1)e.w. des snlniaur 6311s vert. dkouverta dins le tmsh de 1':iris. 111. 155, p1. 80. 4gs. E-23. I!N~I;. I'otamidry /aniawki ('OBSMANN. Ess:ils de P:iI&oronc.li. Comp., Vll, 103.

~lufir.n~.,\rewra: lxiigtli. 22.8 iiini. ; greatest di:irneter. 0.6 iiru. ; :iplcal angle. I!)' ; sutuwl :ingle, 88.5".

The protoconch of this species is beautifully preserved on a small individual of seventeen volutiom. The form i8 similar to that of Certthium adansoni, and the surface is smooth and shining. It comprises about one and one-half volutions, after which two fine spirals of equal Rtrength appear and remain the only ornamentation of the sliell for three volutiom. On the fifth volution the spirals are crossed by ribs, and for the next four volutions the shell has the characteristic ornamentation of the young Cerithium-that is, an angular outline formed by two equal spirals crossed by ribs. On the ninth volutian a third spiral is added just below the suture, and all the spirals form nodes where crossed by the ribs. The median row of node8 lags slightly behind the others, so that the ribs are ciirved in crossing the volutions. The ornamentation of the adult consist~of three strong nodose spirals which are rectangular in croas-section and a fine continuous Rpiral just above the mture. The ribs are faint or obsolete in the adult, and the entire surface of the shell is covered bv Pxtremely fine, clofielp wt spirals. which are only visible with a etrong lens. Same fipwimen8 fihoa gerontic characters in the thickening of the shell and the lo~sof the nndrs on the body volution. The lower slope of this volution hrars three fipiralfi in addition to thnsr alreadv mentioned. The apprture is nearl! circular. The callu8 of the inner lip is thin and Rpread out broadly over the lower fiurface of the hodv volution, and WOOL), 1'1iYLOOB.V 1. OF CERTAIN CERITHIIDB 61 the outer lip is thin and strongly sinuous. The anterior canal is very short, shallow and has a reflexed margin.

HOEIZONAND LOCALITY : 01@33lk. Aurlllac. Par18 Bash. So. 20153, Coluubla Universltg collectlon.

HEMARKS: This species follows the same path of evolution as CerG thium udunsoni for the first nine volutions, but is more retarded in the development of ribs than that species. After the ninth volution the shoulder is lost, and the species diverges from the Cerithium line of evolution. The adult has flattened volutions and an ornamentation of row8 of nodes instead of the angular outline of the whorls and several orders of spirals characteristic of Cerithium. As compared with Eocenic species of C'erithium-C. quispiruk, for example-Potamides lumurcki is more primitive in structure, having a less well-developed canal and simpler type of ornamentation, and it represents, as noted in connection with the genus, the persistence of a primitive form while more rapid evolution was taking place in related groups.

Potamides cordieri mut. typum n. mut.

1824. Ccrifhium cordieri viir. a Desrtaues. Dew. des cognllles lose. da en- rlroun de I'arls. 11, %%. pl. 62. flg. 8.

MmwaebiErvTs : Length. 29.8 inm. : gre:itrst dlameter, 11.5 mm. : aplcal angle. 25" : ~uturalangle, 84.5".

The youngest volution presrnt is .6 mm. in diameter and is ornamented hp ribs and two equal spirals. The same ornamentation continues for four volutions, and on the fifth a nodose epiral appears just below the suture. This spiral increases in strength and becomes more distinctly nodose until, on the eleventh of the volutions preserved, it is as strong as the two nodow spirals below it. .It thiA stage the general outline of the voliition is straight and parallel with the slope of the spire, and its surfare it7 ornamented bv thrw equal rnws of nodes without ribs. The same ornamentation is continned until the fourteenth volution, when the loose coiling reveals a continuous spiral just above the suture. On the fifternth volution present a fine, dightly nodose Rpiral appears between the two upper rowfi of nndefi. The fiame kind of ornamentation continues throughout the remaining whorls. The body volution has three row8 of strong nodefi- +np fine intrrralatpd row and two strong continuous Rpirala helnw thr nrnamentatinn nf nndes. On the later part of this voln- tim the pwth linw mr crmdcd. the Phell snmernlgd thirkrnrd and the nndeR indiptinct or obsnletp 62 .4h’,?‘ALS .%l

IIUXIZOS A.NU IUC.AI.ITI~~: S:IIIIW Aloyeils. 1.a Cliapelle. Le Guepelle and otl1t.r locnlltles In the 1’:iris Ikisiii. No. 20153. Columblu ~‘ulversltytdlwtlou.

l(l:~1.411Ks: \\‘c,rc. 11 IIII~ ior IIII. (~ld-agc.f’cjatures Imwnt on tlw laler part of the body whorl, this variety might be taken for the young of the type species mentioned below, but the shell appears In all ways like a full- grown individual, with a length only about half that of P. cordicri. The development of this form is closely similar to that of P. lamarcki. and the adult differs but slightly in general appearance. It is, however, larger, has a wihapiml ariglc and Iaclis t11~rstrrmely fine spirals covering the surface between the nodes as in P. lamurcki.

Potamides cordieri Dtskayrs

1821. Cerllhfrrm cordicri 1)EBiIiAYEB. Desc. dea coqullle8 fosn. des enVlrfm de I’:iris. II. XM, 111. ,712, Hss. 14. 15, IN(;(;. f’crithirm wrrlio i I~HAY~..~.Drsca. ties :~niiii:iiix s:ins vert. dkouverts ~:IIIN Ir 11:isslri ti(* l’:ii-ls, Ill. I:{;. I!M)Ii. I’fl(ri~opofo?t~ldcrcordiml c0SSMArUN. Ess:lls de Pnlforoneb. (hillp. \I I. 10%

I~EAHLT~EMEN‘TR’ Iknetli. (i0 nun. ; greutest diameter, 20 mrn. ; aplrnl angle. 23.3“ ; sutur:il :infile. !No. The only specimen of this specie8 available for dudy is broken at the apex, but enough remains to show that the devcloprnent of this hell is

Iikv that i)f tlw iiii~taiitiit hypm and rcmainfi the siimr in :ill wivs rxcept in the niiinhi~of spiralfi on the last two or three volutions. P. rordieri differs from ite miitation only in its greater size and in the fact that while P. cortliki mut. tpim hat3 only one row of fine nodes intercalated hetween the Coarser ones, the type Rperies ha^ a similar row intercalated hetween the. two lowrr and also helow the lowefit of the thrw rows of strong nodw The intrrcalation of fine nodes in the remaining inter- spac~would naturally follow their introduction in one of them, so that the adult P. rordipsi constitiites the next step in this line of evolotion beyond that of P. cordi(4 rnnt. typum. For this reason it would have been more appropriate to cmsider the mutation typvm the tvpe Ppecies; hut the name being already estahhhed for the larger RpecimenA, it should not be changed.

fi(lR17OA ANn 1*~.+I ilirn >,,!.I.-- 31e~\w1n I.,, (‘htllM-llv l~lldol)ler lornlttlm 111 the Pnrlr R:I~II .xi) zo1.v. ~~lb~lllll~~l.,I ..,. 11> ..,lln llq,l, REMARKS:Potamides cordieri and its mutation are referred by M. Cossmann to Ptychopotamides, a genus which is distinguished from Potamides by the presence of a colu~nrllarplication, but such a plication is certainly absent from all of the eleven specimens studied, and the close similarity in development between this form and P. lamarckc has led to the placing of the species in the genus Potarnides.

Potamides involutum Lamor, k

1W. CPt*fhium i?tVOh/tit?/i 1.AbIABCK. AIlll. du >!US. Nilt. d’hlst. natUrellt! de I’arls. 111. 318. 1824. (‘crithfuvi ini‘o/itftwi r)KSilAYES. 1)esc.. des coquilles loss. des environs de Parin. 11. 328, pl. 41. flp. 10-13. I!J(%. ?‘prpUflotonll!s ~nlYdrrlunl(‘OssblaSS. Ess:llS de I’~~ho11ch.(hJ1p.. VII. 120.

?dEA3LXEblEATS : J.WIgI1J. 20 111l11. ; #r?:lt?St l~i~llll~~te~,10 nlU. ; ll])!C:ll llll~le. 2.5” ; siiturril :~rigIe.8io.

The youngest volution seen on this Epe‘.ieS is .8 nm. in diaineter. 1 t has at this stage ribs and two CAI[IJ~I spirals. ‘l’lie s;iine ornamentatioil continues for thrre volutions, and on the fourth a third spiral is introduced above the two alrrady existing. ‘I’hts spiral incrcaws gr:idualIy in strength until, on the caighth volution, it is as strong ;is the two hrlow it. At this stage the shoulder ha3 tlrsiippt~iircvl,and the aiirfiiw IH ornamented by three equal rows of nodes and a fine continuous vpiral just ahove the suture. On the later whorls, at a stage varying in different individuals, the nodcs are lost, leaving t lir siirfacr msrked hy continuoua spirals only. Still later the two lower spirals also dis:ippoiir, leaving a single spiral which forms the margin of a strong shoulder angle just hrlow the suture. The extent of this smoothing of the shrll v:irirq grratlp on differrnt individiisl~,ocriip!ing thrrr nr more ~oliitinns,or the Rpirals, and even the nodes, may persist nrarlv to the end of thr hodv volution. Specimens on which the smooth portion comprises srvrral vo~ntionshave also a narrower angle of slnpr for thr Rides in this portion of the shell, indicating :i flattening nf thr whorls parallcl to thr ayiq of wiling. The emhracing of the whorls is greater than in thr young portion of the shell, and on wme Rprriincns also a distinct ram1 is formed at the postrrior margin of the ~pertnrehy this overlapping of s fold in the outer lip npon the prrrrding whorl. The npertnrr is rlowlv similar tn that of I’ofomir/er /,inr.ar. ki Thr aiphonal canal is Rhort and widrlv nprn. thp calluR of the innrr lip 1hic.k. and the marein of thr nnt~rlip Rtrongly siniioucl.

fh17nn AmIAXAI.ITY V;II~-;IIW Croxsicr (‘iiiw I,, ,,,.,(I~ I’,~,in I%.,~I~. SO. M1.55. Colunihln I‘iilwrdtv nJlwtlon 64 ANNALS .\El+' I'ORK .4CADEdlY OF SCIENCE8

BEMARKS:The shells included under this name form a perfect gradational series from forms in which the loss of nodes appeare only on the later part of the body volution to those in which both nodes and spirals are absent, if we include the forms figured by Deshayes, from nearly the whole surface. So perfect is the gradation in the collection studied that hardly two individuals are alike, and each may be considered a mutation, though for convenience they are described under one name. The loss of ornsmc~ntation,the flattening of the whorls and the overlapping of the later whorls upon the earlier are all old-age features which indicate a progressive gerontism and approaching extinction in the branch of evolution which they represent. The life hist.ory of this species is closely similar to that of P. cordien' mut. tiypicum. down to the stage when gerontic features begin to appear. It differs from that species in having a wider apical angle, but the two species are doubtless closelv related.

The youngest volution studied is .8 mm. in diameter, and there arc evidently several solutions missing above this. Ita ornamentation consists of two very fine, equal, continuous spirals. On the next volution thew spirals are crossed by very faintly developed, oblique ribs which are prrwnt with varving fitrength and freqiiencv on the succeeding ten volutiona. Thew rihs an; never well developed, and on the adolescent and adult whorls they piw place altogether to crowded line8 of growth. On the later voliitiona thc qpiral~also hrcomc indistinct, and the whorls have a rminded outline. with a Rurface roiiglirned hv the crowded lines of pwth and faint trscw of nne or two spirah. On the voung of Rome pperimcnR the lonw of thr taro spiral^ is more prominent than the upper, and thp rihs in rrwainy girt. it R nodofie appearance, hut thie omamenta- tion also disappears from thc later aliorlrr. The apcrliirc is rirviilar. with a thickened rallu~on the inner lip, and the marein nf thr oiitrr lip is siniinii~ The Fiphonal canal is shallow and hroad. with a atronglv rdlrwd margin. 1YOOU. PUYLOGEX Y OP CERTA1:V CEH1TlflIDii3 65

HOEIZOLTAND LOCALITIEB: Calcalre grossler. La Frlleuse and many other localltles In the Pnrls Bash * No. 2015'7, Calurnbla Unlversity collection.

REMAEHS: The highest development of ornamentation on this shell advances but little beyond the stage with two simple spirals represented by the second to the fourth volutiona of P. lamrcki, and the development of the ribs is so feeble as to correspond with only the earlier part of the fifth volution of that species. P. luptdum is doubtless developed from the same ancestor aa P. lumurcki, but since in the adult it becomes more smooth, instead of developing a higher degree of ornamentation in the direction of P. lamwcki, it probably represents a lateral branch frqm the main Potamides line of evolution.

'The earliest stageA in the cjcvelopmt,nt of thr gerio1,vpe sliow that this fihcll ifi derived from the same stock as the true Cedhium, but it diverges from the main line of evolution so Rtrorigly and at srich an earlv stage that it deserves to rank as n distinct genus. Id. Cossrnann dcscrilies Potamidopsis as a suh-genus of Polamitlrs, Ijut the grorrp is rnorr closely rdated t.o C~rithimnthan to Potamitlps: hcnct it phould not rank ap a suh-genus of the lattrr. It in also loo rlislantly related to f'~Rtttiiimto constitute a mh-genup of that group, and hence it is here rankc4 as an independent genus. To the di~tIrrpuI~hingrhsractera eniirnrrstrd hv M. Cowmnnn may be adad the niimeroua vohtions producing a very high +re; the close emhracing of the whorh; the general outline of the volutions, not convex, hut cnnforming to the dope of the spire; the high dewlopment of nodes and the absence of rib8 on all except the nepionic volutinnn of the Rhell. Thr apertiirt alw varies in its anplsr outhnp- 66 ASNALS NEW YORK ACADEMY OP SCIENCES the broad and thick callus of the inner lip, with no trace of posterior tooth, and the short, oblique siphonal canal. The outer lip is often thickened, and its anterior portion grows more rapidly than the posterior part, making the outline of the mar@ strongly sinuous.

Potamidopsis tricarinata Lumarck

Plate VII, figs. 7, 8; plate VI~J,figs. ?, 8; plate IX,figs. 7, 8.

1804. Cetithium lricaritiatuiri LAMABCK,Ann. du Mus. Nnt. d'hlst nnturelle, 111, 272, Mo. 4. 1824. Cerithfum frlcarrnalum DESHAYE~,Desc. des cvqullles foss. des envlrone de I'arlu, 11, 325, pl. 51, flgs. 1, 8. 1!#i6, ('crrlhium /ricariirafrrm DmiAYEe, 1)esc.. deu anlm. sans vert. dhuverts (inns le bassln de Purls. 111. 11. 123. lrjo2. Potarnfdes trtcarinotum C~SSMANN,Catal. Illust. des qullles loss. de 1'Loc. des enrlrons de Pnris. IV, p. 69. 1!n)3. ~'gtnpunchmIIY trwuritr a t uin ('OSS M A SN. 1% Ieon tologla Unlversnlls, Cent. I. pi. :inp. I. 2. I!WHI. /%futrr~dvp.~i.~Irtcorrnalrrn ('ossatam. Em:jlR de Palhntol. Comp.. VII. 10% pl. 11. figs. 5. (i. ~~EASUHEYENTS' ~AWgfh. 15 11II11. ; grP;ItWt dlaniet~r,17 IDID. ; IJpkYll angle, ; NUtUrlll :II&, Hi"

The early stages of the species are described from a young individual of fifteen volutions. The protoconch is missing, but the youngest volution preserved is probably the first beyond the protoconch, as it has a diametrr of only .3 mm. It has an ornamentation of two equal spirals without ribs, and the same ornamentation persists on the next volution. Ribs appear on the third voliition, which has an ornamentation exactly sjmilar to the adult of Cerithium Bic~minalun. On the fourth voliition the lower spiral becomes stronger and the upper one weaker, a tendency which increases on the next three volutions until, on the seventh and eighth volutiona, the upper spiral hns entirely disappeared, and the ornamentation confiiats mrrelp of a single strongly nodose ppiral, forming a projrcting shoulder an& jufit ahove the suture. The ninth volution has a siih-mitural spiral thr noh of which are connwted with tliose of the shoulder an& hy arll-drrrloprd ribs. ThiR tvpe of ornamentation per- Rists for seven volutinn~ more, and on the foiirtrenth voliition a fine spiral is intrrcaletrd hrtacw the two already exieting. Comparing this young individual with an adult, it ip found that the latter is more retarded in the pnath of thiR fine spiral than the former. Tt do@ not - 'The slwrlmen mPanurt4 lo lhr on? whlrh 4wnR 10 rorrr%pondmost elo~rlpmlth the mren of the tppP dren In the Pa~ronto~oplaT'olverualln. rentiirla I. plate 3. flga. I. 2. IVOOU, PLIYLOGBNY OF cfil~r.llsc~l~lTnllD& 67 appear on the adult individual until the sixteenth volution, after which it becomes stronger and soon breaks up into a row of fine nodes placed half way between the two rows already formed. The ribs become discon- tinuous, and the last seven whorls are ornamented by three rows of nodes, of which the lowest forms a projecting shoulder angle just above the suture, and the medxm row is very slightly finer than the upper one. On the later part of the body whorl all the nodes become indistinct or obsolete, where the crowding of the growth lines and thickening of the shell indicate old-age conditions. The aperture is about qua1 in length and width and somewhat angular in outline. The callus of the inner lip is very thick and broad, its posterior part often spreading out for a considerable distance over the posterior part of the body whorl. There is no trace of posterior tooth, as in Cedthium sens. str. The outer lip is often greatly thickened, strongly flaring at the margin, and it overlaps more or less upon the preceding whorl. The thickening of the shell, the 10~of ornamentation and the encroaching of the later part of the body whorl upon the preceding whorl are all old-age features which indicate that the species is approaching its extinction.

Hosrzo~v am LOCALITIEB : Calcalre grossler, Sable Jloyens. Grlpiiori iirid m:ing other Ioralltles ln the Parts Ussln. No. 20122. Columbla Unlvemlty collertlon.

KEMAEKS: The young stages of thiA spcwies furnish a clue to its development from Iform resembling Cerithtum birarinatum, pinre ih development for the first four volutiona is closelv parallel to the developrnent of that species, and the fourth volution (counting tlie protoconch as one) is the counterpart of the adult C. bwarinalum. The species could not, however, have been developed from C. bira~inatunz itself, since it wurR at an earlier horizon, but was probably developed from the pre-Juraisic anceetor of C. bicarinutum mentioned in connection with that speci~s-- the same ancator which probably gave rise along a different path of evolution to C. corallense and its descendants, C. ~qih1n’rale.C. tuberu- sum, etcetera. Polamirlopsis tricahata has developed riiany mutations bv the acwntu- ation or suppresRion of one or another of itR surface featurep. Of these mutatione, Lamarck has descrilwd one and given it the dmignati~~“p,” and Denhayes has indicated five others hv letters from “%” to “f,” the letter “a” being used for the type species. The rnutationfi occur at the same horizon and localities as the type, and, as might be expected, transi- tional forms exint between all of them. 68 ANNALS NEW YORK ACADEMY OF BCIENCEB Potamidopsis tricarinata mut. baucis mut. nov. 1804. Cerithlum tricarinatun var. p LAMABCK,AM. du MUE. Nat. d'hlet nst- urelle, Paris, 111, 272. The author says of this speciw: Dan8 la varlet6 ,9, la carene supkleur de chaque tour est un peu plus eml- nente que celle du milleu.

The mutation is apparently more common than the type species, since it i~ rare to find specimens in which the two upper rows of nodes are equal. The upper row is slightly stronger, even in the type figured in Paleontologia Universalis, but the varietal name may be retained for those forms in which the difference is strongly developed. No. 20121, Colurubta Cnivemlty collectlon.

Potarnidopsis tricarinata mut. brontes mut. nov.

1824. C'rrtfhiuni lricnrinoluni var. b DE~EAYE~,Dew. des coqulllee foss. des environs de I'aris. 11, 325, pl. 61, Bg. 2. This mutation is distinguished by the strong carina which fom a projecting shelf around the whorls and by the fine nodes of the two upper spirals. The shells of thia variety are usually larger than those of the typical form.

So. 20123, Colulubiii Cnivemity collection.

Potamidopsis tricarinata mut. cronus mut. nov

1824. Crrifhhn trtrorinnlum vnr. c DEsIiAYm, Dew. dm coqullles rose. des enrlronfl de ParlR, 11. p. 325, pl. 51, flgfl. 3, 4.

The carina of thi~mutation is also very ctrong, but the nodes are more widely &paced and more prominent than in the mutation brontea. The median row of nodea ifi obsolcte and the upper row is poorly developed.

Potamidopsis tricarinata rnut. dons mut. nov

1x24. ('e7lfhtitni trfcnrinefum Par. d DEBHAYEB. new'. des. Cogillllefl Pow. des PnrironR de P:irIR. 11. p. 326. pl. 51. Bg. G.

This mutation ifi fiimilar to tho la&, but in thia form it is the siih- diiral row of nodes which hecomes obsolete. WOOD, PHYLOGENY OF CEIlTAIW CERITHIIDB 69 Potamidopsis tricarinata rnut. eris mut. nov.

1824. Cerfthfunr tricarinaluer var. e DEEIIAYEE,Desc. des coqullles foss. des envlrons de Paris, 11, 326, pl. 51, tlgs. 4, 7. On this species the carina is not prominent, and its nodes are nearly obsolete, leaving the margin but slightly wavy. The two upper rows of nodes are present.

Potamidopsis tricarinata rnut. fatua mut. nov.

1824. Cerithium tricaflmfum var. f DESHAYE~,Dew. des coqullles foss. des envlrons de Paris, 11, p. 326, p1. 51, flg. 9.

This is an extreme mutation, which IS distinguished by the almost entire absence of nodes, in the adult stages, from both the carina and the two spirals above it. The varia.tion is carried so far in this form that it would be described a a distinct species if the nodes had altogether disappeared. Potamidopsis acus Deshayes

18(i(i. CerifWiunr QCUS DEsriAYEs, Dew. des nnluiaux Bnna vert. dhuverte dans le bussln de Pnrls, 111. 199, pl. 75,‘flgs. 19, 20. MEASUBEbfENTe (Deshayes) : Length, 25 mm.; gI’eatt?St dlnmeter. 6 mm. Deshayes records the discovery of a single specimen only of this species. According to his figures and description, it has a long, slender spire of twenty-five volutions. The adult is ornaniented by two rows of nodes connected by ribs, the lower row being more prominent than the upper. A fine undulating spiral is present just above the suture. The aperture is like that of P. t~icarinala.except that it does not show gerontic characters in the thickening of the shell and loss of ornamentation seen on many specimens of the former species. Deshayes calls attention to the ~imilarityof this shell to the young P. tn’carinata, and it might be considered the young of that species were it not that all the specimens of P. lricarinata studied, of 25 mrn. in length or of twenty-five volutions, have passed beyond the stage represented by the last whorl of P. ~‘1~sin the intercalation of a finely nodose spiral between those already existing. If P. acus is actually adult, a~ it appears to be, it represents a more primitive form than P. trirarinata and may well be the immediate anrefitor of that species. This hvpothesk would be confirmed if other RperimrnR showing yoiing stages similar to those of the very young P. trirarinata were discovered.

I~~EIZONAND LOCALITY : CalcaIre groanler. Blonchy. Parh R~N~II 70 .4SSAI-8 XEIV I’ORK lCADEYY OF SCIEXCEB

Potamidopsis dxta Deshayes

Cerfthium mlrlum DEFRANCE,Nom. nu& 1&4. Cerilhiuvi ?tlfrtlt7/1 DESHAYES,Desc. des coqullles foss. des envlrons de I’arls, 11. 324, pl. 45, flgs. 6-11. 18C;ci. C‘c~ritkiut~iniist~rm DESHAYES, Desc. des anlmaux sans vert. dhuverts dam le bassln de Parls, Ill, 123. 1W. Ptychopotaniides wicriuni C~SSMANN,Essals de Palbconch. Comp., VII, 108.

MWSOREMERTS: Length of the eleven volutlons preserved, 41 mm. ; greatest dlameter, 15 mm.; aplv:il angle, 27.5’, changlng to 21.8’ on last three volutlons; sutural angle, €0’. The youngest volution preserved on the shell studied is 3 mm. in diameter; hence a considerable portion of the apes has been broken away. The first three volutions are much worn, destroying all the finer surface features, but the fourth has precisely the ornamentation of P. tricarkta mut. bronles, namely, a strong nodose canna near the hase of the volution, a sub-sutural rinv of rather strong nodes and a median row of nodes much finer than either of the others. This remains the ornamentation of the shell until the third from the last volution, when the sub- sutural and the Io\wst row of nodes become equal in strength, finer and much crowded. A fourth, finely nodose carina is developed at the base of the volution and is partially concealctf by the succeeding whorl. On the hod! volution th(8 nodes of the upper row are small and in places so close together as to become confluent. Two nodose carina and several fine spirals are present on the lower slope of the body volution. The aperture is similar to that of P. tricurinala. with an expanded callufl on the inner lip and a comparatively long, twisted siphonal canal. A slight colr~~nellarplIcation defines the pmterior margin of the canal. The outer lip is hroken in the Ppecimen at hand, but the figures of Deshayes, cited ahove, fihow it to be Rimilar to that of P. tricariwta.

1Iowzoh’ AND IIWAI.ITIRS ’ Rnbl~nMoyens. Anrer8 and other localitlea In the I’nrlR R:i~ln. So. 20147, Colnnlhln 1~niwrRlt.vcollectlon.

I~~AIIKS: So far aR can he determined, the life history of this Rpecies IS like that of P. tricarinaia until the last three volutions, when the ornamentation change8 to that of three row of crowded nodes, the uppemoRt being slightly more prominent than the lowest. It is probably a de- wendant of P. tr~rnf-inaln.Rhowing it,R divergence from ita ancestor on the lafit three volutione only. The cnliimnellar plication which furnishe8 the reason for placing thiR WOOD, l’If1’LOGESY OP CERTAIN CERITHIIDB 71 species in the genus Ptychopotamides is indistinct, and does not constitute a sufficient reason for separating the species from the group to which it is closely related in its development.

Potamidopsis tubcrculosa Latnarrk

1W. Ceritltiuni tubf?r’Culo8unt LAMALBCK,Ann. du Mus. Nat. dhlst naturelle, 111, 348. 1824. Cerithiuni twberculorum DESHAYES, Dew. des coquilles foss. des envfrona de Parls, 11, 48. figs. 1-5. IMti. C’erfthCp~tuberculosuni DESI~AYES.Dew. der! anlmaux snns rert dho- rerts dans le bassln de Parls, 111, 122. liW. Serrutocerilhhrn tuberculovuni C~~SMANN.Essals de Palhnch. amp., VII, 56.

JlEasumbfiENTs: Length, 33 IUIII. ; greatest diameter. 12.2 mm. ; aplcal angle, 26”; suturul nngle. 88.4’.

The early stages of this species are described from a young individual uf fifteen volutions. ”lie protoconch of the specimen is missing, and the first two volutions are too much worn to show the surface ornamentation, but the third volution present is ornamented by a sub-sutural spiral and a stronger spiral forming a slioulder angle just above the suture. Both spirals are rendered nodose and connected by ribs which are continuous across the volutions. This type of ornamentation persists for five volutions and is closely similar to the ornamentation of P. t7icarinala at a sliglitly later stage. The nodes of the lower and upper rows gradually become equal in strength, and the shoulder disappears. On tlw sixth volution of those preserved a spiral is intercalated between the two row8 of nodes already formed, and two volutions later thiR spiral is hroken up into a row of very fine nodes. The ornamentation at this stage resembles that of P. tn’curinata at the same stage, except that the lower row of nodes is more prominent on the latter species. At the eleventh volution the nodes of the Rub-sutural row become more prominent and more widely spaced than those of the lowest row. This tendency increafies until a shoulder angle composcd of Rtrong, transversely elongate nodes is formed just below the Ruture. This lwomes the ornamentation of the adult shell, except that a fourth spiral which is partially exposed jmt Above the sutnre also hecomes wavy or faintlv nodose. The body volution Bears one nodose ridge in addition to those already described and several fine spirals on its lower slope. The aperture iA nearly circular. The callus of the inncar lip IS hrr~tl and thin. The outer lip is thin. its itiargin, growinp mow rapicll? .II 72 ANN.4LS NEW YORK ACADEMY OP XCIENCEIP the anterior portion, gives it a sinuous outline. The siphonal canal is broad and deep, bordered by a strong ridge on its columellar side.

HOEUONAND WCALJTIEB: Sables Moyens (Upper Eocenlc). Wldely dlstrlb- uted In the Paris Basin. No. 2u148, Columbiu University cvllectlon. Renimrrs: The earliest volutionv of this shell are missing, but the youngest preserved has an ornamentation similar to that of the ninth to the thirteenth volutions of Potamiclopsis tn'carimta. It adds an intercalated spiral as in the latter species, but it diverges from the line of evolution represented by P. tricaPinata by forming its shoulder angle at the upper instead of the lower margin of the whorl. This specibs may be regarded as derived from the same ancestral stock BB P. tricarinata, but it represents a divergent line of evolution. 11. Cossmann refers this species to 8erratocerithium, a sub-genus founded mainly on characters of the aperture, but the aperture of P. tw.berculosa does not appear to differ to a marked degree from that of P. trzcarinata. The canal is slightly longer and the outer lip thinner and less flaring. The present reference of the species, being founded on descent 8~ revealed by the ontogeny, necessarily arrives at a different rcsult from one founded on adult characters alone.

Potamidopsia roissyi Deshyes

1R21. ('c~rifhfvm roissi/i DESNAYEB.Dew. dea c~qulllmfoas. dea envlrons de I'nria, 11, 3T2, pl. 50. Bgs. 13-20. 18GO. f'erfllrfam roixnyl DEsiuYEs. Drsc. dea anlrn. enna vert. dbuverb dane ie busdn de Paris, p. 127. 1!0i. Tympunotonue rofssyf COOGBMANR.EES~IR de Palkronrh. Comp., VII, 120. hfE~sumMEms: Length, 25.7 mm. ; greatest dlameter, 8 mm.; aplcnl angle. 20" : sutural angle. go".

'I'he protoconch is missing from the best Rpecimen available, and it ia probeble that two or three more volutions are also broken away. The youngest volntion prefient is .7 mm. in diameter, and it hm exactly the ornamentation of P. trican'nata from the ninth to the thirteenth volutions. The. same ortiamentation continues for four volutiona, after which the ribs disappear and the two rows of nodes become equal in strength and often alternate in poRition a8 compared across the whorl. On the sixth volution a fine Apiral j, intercalated at about the middle of the rolution. This spiral Roon breaks up into a row of extremely fine nodes. At about the same Rtage of growth the sub-sutural row of nodes hecome@stronger than the oth~rs,a tendencv which increases until the WOOD, PHYLOGENY OF C6RTdIN CERITHIIDB 13 adult condition is reached. The ornamentation of the adult comista of three rows of nodes of which the upper are larger and more widely spaced than the others, and the nodes of the median row are very he. An irregularly nodose hespiral is barely visible just above the suture. The body volution has two strong spirals below those already mentioned. On this volution the growth lines becoiiie very much crowded, and all the nodes become indistinct, especially toward the later part of the volution. The aperture is about equal in length and breadth and is roughly quadrangular in outline. The callus of the inner lip is broad and thin. The siphonal canal is short, widely open and somewhat twisted. The outer lip is thin and has a strongly sinuous outline.

HOBIZONAND LOCALITY : Sable8 Aloyeus superleur (Upper Eocenlc). La Chsplle, Par18 Bash So. 20149, Columbln Uulverslty c.ollect1on. REMARIM:The ornamentation of this species closely resembles that of P. tuberculosa, both in its development and in the adult stage. The species differs from P. tubercu.losa in its smaller size; narrower apical angle, which makes it a more slender shell; its shorter canal and more angular aperture. 'f'his species bears the same relation to P. Iricu7inata as does P. tubereu- ha-that is, it iR derived from the same ancestor as both, but develops in the direction of P. tuberculosa, to which it is closely related.

Potamidopsis crassinoda sp. nov

MEABCERMENTB; I,rngth of sprclnien wlth riplcal whorls mlsslng, 39.8 mm. ; greatent dhmrtrr. 2i.i IIIIII. ; iipIc;~langle. :En.(*hanglug to 23.8' on the slxtb volutlon ; suturnl nngle. 85'.

This species is distinguished frnin f'dntnidopais tubcrrulosa. to which it is closely related, in being a 1argt.r and tlh~kerfihell and in having thc nodes of the surface much larger nnd more prominent. ThiR difference begins at an early stage of growth and continues throughout the life of the animal. The youngest volutinn prrsrrvrd is 2.5 mm. in diameter, and several whorl8 have evidentl! hem hrokcn away above this. The first three volution~have an ornamentation of ahout the same strength and character a8 the adult of P. ItLt)erculoca, but beyond thiR the large nodes characteristic of all the later rolutions are developetl. The nodes of the uppermost row arr larp. Idlint cones; thofie of the lowest row, smaller and transversely elongate. The median nodee nre very fine and on some specimens nearly obsolete. The base of the volution iR produced into lobes, which Rometimrs nwrhang the wcceeding volution. 74 ANNALB NEW YORK ACADEMY OF SClENOEi3

The aperture is similar to that of P. tubercdosu, but the canal is longer and more strongly reflexed, and the due of the inner lip is thicker and is not closely applied to the surface of the shell. The outer lip is thickened with crowding of the growth line and lose of ornamentation for some distance back of it.

HOEIZONAND LOCALITY : Sables Moyena Rowyen-multlm, Parls Bash. KO. 20150, Columbla Unlverslty collection. REMARKS:This species haa been regarded as a variety of Potamidopsis tuberculosu, but its much greater size, strongly marked surface featurea, and longer siphonal canal, aa well a~ its more accelerated development, entitle it to rank as a distinct species. It is evidently derived from the same ancestor as P. tubcrculosa, following the same path of evolution but strengthening all the features of the shell. The three species, P. roissyi, P. tuberculosa and P. crassinoda, possess the same type of ornamentation, and they form a series in which P. roissyi is at one extreme, characterized by small size, thin shell and delicacy of ornament, and P. crassinodu, at the other, characterized by thick shell, strong tubercles and wide apical angle.

Potamidopsis conjuncta Deshayes

1824. ('crithittm conjuttctrrni DESIiAYEE, Dew. dea c!oqullles fosslles dea envlrons de Parls, 11, 387, PI. 73, flgs. 14. IS(%. Cerftkfrm conjuncturn DEsIIAYEs, Desc. des nnlmnux fans verL dhu- rerts dnns le bassln de Pnrls, 111, 123, pl. 80, 6gS. 9-16. 1WJ. Ty?rtponolonus conjuncftis C~~SMAXN,Es~sls de PuhcoDch. Comp., VII. 120.

MEARLXEMENTE:I~ii~tli of slwluien from whlrh apex Is broken, 29.4 mm.; greatest dhrueter. 10.8 iimi. ; ap1c:il angle, 28.2". changlng to 18.2' on the last. three volutlonn; sutur:iI angle. 86".

The YoiingeRt volution availahle for study ia 2 mm. in diameter, and several roliitions have been broken away above it. The ornamentation ia that of two rows of nodes, one near each suture, the lower row being the more prominent. The upper and lower nodes are connected by ribs. ThiR ornamentation resrmble~that of P. tricannata from the ninth to the thirteenth volutions. On the third volution present a fine spiral iB intercalated between the two rows of nodes. This spiral soon becornea finely nodose, and the ornament of the adult is that of three rowB of nodes of which the uppermoat and lowest are large and of equal size, while the nodes of the median row are very small. The body volution hm two ptrong spiral8 and several fine one6 on its lower slope. WOOD, PHYLOQENY OF CERTAIN CERlTHllDB 75 The aperture is roughly quadrangular. The callus of the inner lip is thick and expanded posteriorly. The siplional canal is 61iort, twisted and has a strong columellar ridge defining ita posterior margin. The outer lip is broken in the specimens studied, but, according to the figures of Deshayes, cited above, it is thin and strongly sinuous.

I~ORIZONAND WCALITY : Ollgocenic. Jeures, Park Bash So. 20151, Columbia Unlverslty collection. I~EMARKS:The development of this shell is closely similar to that of P. tn'curtnatu, 80 far as can be det.ermined from the specimens studied. The adult differs only in the fact that the lowest row of nodes equals the uppermost in prominence, instead of exceeding it. This causes the outline of the volution to be parallel with the slope of the spire, instead of forming a shoulder. P. conjuncta probably occupies about the same relation to P. tricurinuta as does P. tuberculosu, diverging from the trL curinuta line of evolution at about the same stage in ita development, but in a different direction. The adult of P. tricurinata show8 greater prominence of the lowest row of nodes; that of 1'. tuberculosa emphasizes the prominence of the sub-sutural row, and in P. conjunctu they are equal.

Potamidopsis trochleare Latnarck

1804. C'crlfhiuni trochlrare IAMARCK, Ann. du Mus. d'hlst nnturelle. 111, 349. 1x24. C'erifhii/m frochleare DEBHAYES.Dew. des coqullles loss. des envlrone de Pnrls, 11, 388, pl. 55. figs. 10. 11. 1Xlili. Cvrilhiwni frorhleare DEBIIAYES,Dew. defl nnlmsux sans vert. dkwuverts dnnR le bassln de I'nrlR, 111. 129, pI. 80, dg8. 1-8. l!KN;. Tytnpatiotoiius frochlcafe CCJBSMANN,ERS~~R de PaI6omnrh. C!mp.. VII. 118, pi. 11, Bg. 19.

MEASUREMENTS: Leiigth, 25 UIUI. ; grc:itclit tl1:imcter. 12 mm. ; apical angle, 25.2" ; suturiil angle. 89".

One of the specimens Btudied shows the protoconch. This is similar in form to the protoconch of Cerithiunz adansoni and cornprism about one and one-half volutions. The volutions immediately succeeding the protoconch on this specimen are poorly preserved ; but another specimen, whose youngefit volution iA .7 mm. in diameter, retains the surface features. This is the third volution, a9 shown by comparison with a complete individual. It is ornamented hv two nodose spirals, of which the lower is the more prominent, and a third fine intercalated spiral. This is the ornamentation of the adult P. tiirnrinafa. The median spiral persists for two voliitionfi only. after which the ~hrllhas two row of nodeR only, with the lower more prominent than the upper. The latter stage 76 ANNALS NEW YORK ACADNMY OF SCIENCE8 lasts for a variable number of volutions on different specimens, bui usually from five to eight volutions. Beyond this the ribs disappear, and the shell is ornamented for the remainder of ita growth by two extremely prominent continuous spirals with deep concave depressions between them. A third spiral, partly concealed by the embracing of the whorh, is shown on the body volution to be less prominent than the others. The aperture is distinctly quadrangular. The callus of the inner lip is thick and rather narrow. The siphonal canal is short and deep. The outer lip is often thickened in large individuals, sinuous and folded into lobes to correspond with the spirals of the outer surface.

I~OHIZONAND LOCALITIES : Oligocenic. Morlgny, Jeures and many other localities In the Parls Basin. So. 20152, Columbia Unlverslty collection. REMARKS:The youngest volution of this species to show the surface has the ornamentation of the adult P. tricurinata. The first change to take place in this ornamentation is in the loss of the median spiral, which was the last feature to be acquired in the development of the latter species. The succeeding three or four volutions of P. trochleare correspond with a still younger stage of P. tricurinatu, namely, that with two row8 of nodes only. The adult P. trocldeure has two continuous spirals, as in the earliest stages of P. tricurinatu. The facts thus far stated seem to indicate a loss of characters by gerontism and the return to the primitive conditions of an ancestor, but that this is not the case is shown by a study of the intervening stages of P. tricun'natu. Studying the development of that species in reverse order, the stage preceding that with two rows of nodes only is one in which the sub-sutural row of nodes is absent, and, earlier still, a fine spiral is present immediately above the shoulder spiral (plate VIII. fig. 7). This is not the same feature as the median row of nodm in the adult, although it occupies the aame position, because it disappears and gives place to another character before the appearance of the adult median nodes. It is this spiral, however, which, on the fourth volution, iR as strong as the 8piral at the shoulder angle and form the upper of the two,continuouR spirals on the second volution. Tn P. trochleare. on the contrary, it is the sub-sutural spiral which p'ersisb and form8 the upper of the two strong Rpirals in the adult. The lower of the two corresponds with the Rpiral at the shoulder angle in P. tricarinata. TheRe two spirals have not the rhararter of primitive wtructurrm, but are on the contrary, extreme in their development. P. trorhlenre is a de- Rcendant of P. tn'cariflata. with itR youngest stages like the adult of the WOOD, PliYLOffEKY OP CERTAIN CEnl!i'€iIIDB 77 latter species. From this stage it progresses toward simplification of surface forms rather than complication of them, as in the species previously described. It illustrates the fact that progressive development does not always mean complication of structures, but may also travel in the direction of simplification of structures. Although P. kochleure does not add new types of ornamentation, it does emphasize strongly the one feature retained in the extreme prominence of its two continuous spirals. Illustrations of progressive development resulting in more simple structures are found in other genera ; for example, Cluviger matoni GRAYhas young stages in which the whorls are ornamented by four strong spiral8 crossed by numerous oblique ribs, changing abruptly to an ornamentation of two very prominent continuous spirals, but without other features to indicate gerontism as a cause for the loss of ornamentation. Deshayes's figures of this species, cited above, indicate an extreme degree of variation, including forms with three spirals, or one spiral, or rows of strong nodes, and it is probable that several of these should be considered distinct species. In the absence of specimens showing these variations, they will not be considered here.

6. Vulgocerithium

Vulgocerithium minutum de Serres

1822. Certfhtvni mlnutrm DE SEEBEB.Essnl pour servlr n I'hlRtOlre dw nnlm. dn mldl de la Fmnce, p. go. 1RW Crrifhfvmmhitfum HOENEEnnd I'AETWH. Ahhand. der k. k. geol. Relch- snnst., 111, 390, pl. 41. flg8. 8, 9.

VRAAWEMENTB:Length, 25 nini.; greotwt dinmeter. 9 mm. ; aplcal angle, 33.6'", changing to 16" on the laat four volutlons; sutural angle, &?.5'. The youngmt volution prewrved on the specimen studied is 1.2 mm. in diameter. It has a well-defined fihoulder with two strong spirals, one finer intercalated ~pirnl and four on the shoulder. On the next two volutions the sub-sutural epiral become8 hroad, another spiral is add4 between the two primaries, and one appeam on the lower slope of 'the whorl. On the succeeding volutions the sub-sutural spirals become ele- rated at inkrvals as a row of nodw. the lower dope of the volution he- come8 nearlv continiiou~with it9 vrrtical side3 and numerouR intrrcalated Rpirals appear. The adult ornamcntation is that of a ~uh-sutiiralrow of nodes, a median row with norle.c diphtly more prominent than thofie of the upper row and rihfi which are more or less continuoua toward the lipper eutnre hut are representrrl hy irrepilarly spared nodes below the 58 ANNALS NEW YORK ACADEJIY OF SCIRSCES median line. The shoulder on the last three volutions is nearly obsolete, being defined merely by the median row of low nodes. The aperture is of the form usual in this group, with a narrow callus on the inner lip, a strong posterior tooth and a short anterior canal. The outer lip is thin and slightly crenulated.

HORIZONAND LOCALITY : Upper Ollgocenlc (Aqultanlan). Stlucats, France. No. 3123, Museum of Couiparatlve zO6log.v.

REMARKS: This species continues into the Miocenic, but the specimens studied are from the Oligocenic. Except for its small size, the shell is closely similar to V. vulgaturn, and it may well be the immediate ancestor of that species.

Vulgocerithium puparforme Basferof?

1825. CerilLfiim pupcfortitc RABTEBOT, Menlolre gQ1. sur lea envlronv de Bor- deaux, p. 58. pI. 3, flg. 18. < IfK)(i. Dizmfopcris pupfffornte COSBMANR. Essnis de Palkoneh. Comp., VII. 147. pl. XII. Bgs. 22-24.

MEABUBEMENTB: Length, 12 inin. ; greatest dlameter, 4.8 mrn. ; aplcsl angle, 36.5". chnnglug to 26" 011 the last tliree volutlon8; sutural nugle, 76'.

The protoconch of this species is not preserved, but a volution .G mm. in diameter probably represents about the second volution beyond it. This whorl is ornamented by two equal spirals, and on the next volution the spirals are crossed by ribs. On the third volution of those preserved a spiral is added between the two primary spirals and one just below the suture. On the later volutions numerous hespirals appear until those of the third order may be recognized. On the body volution the shoulder is le~prominent and the nodes formed by the crossing of the rib8 and the sub-sutural spiral are larger, so that without a lens the surface appeam to be ornamented hy two rows of nodes, the lower of which is formed by the croming of thr ribs and the shoulder. The bodv volution has two or three strong spirals, with finer intercalated ones on ita lower slope. The aperture ie elongate oval, with a broad and thick callua on the inner lip. The sjphonal canal is long and slightly curved. The outer iip is thin and not bxpanded.

Iloarzo~AND IDCALITY : Oligocenlc (Aqultnnlan). Snucats, near Bordeaux. No. 2521, Museum of Conipar;ttlve Zdlogy.

REMARKS:The orignal dewription of Cerithiurn pupaforme hm not hren obtainahle. and the refmncr to this species jR somewhat doubtful. WOOD, PHYLOOEWY OF CEIlTAIN CERITHIIDd 79

The development of this shell, aa well as its adult ornamentation, has all the characteristica of Vulgocerithium. It resembles V. minitum to such an extent that it was at first thought to be the young of that species., but it is more accelerated than V. minutuna, acquiring its tertiary spirals at an early stage. It differs further from the latter species in having a narrower aperture and longer canal. The well-developed callus and nearly uniform size of all of the ten individuals studied seem to indicate that the specimens are fully adult.

F. CEETACIC SPECIES OF CEBITHIUM No actual specimens of true Cerithium from horizons earlier than the Aptien were available for study, and the following phylogeny worked out from the literature is subject to revision, if more material should be obtained. Centhiurn cornuclianum d‘orbigny

1M2.1843. Gerflhirm cornuelian mi D’OBBIGNY.1’0 I6ontol. Franc3 lse, Terralns CrBtaces. 11, GostOropodes. 11. XI, pl. 23, flgn. 11-13. 1906. A lre8lus comitcUonnm CQSSMANN.Essnls de Pal&conch. Comp.. VII, 1%.

The original description is ae follows :

DIMENSIONS: Ouverture de I’angle qJir:ll, 2;’ ; longeur totule. 2i tnllllm. : 1:irpeur. 12 mllllni. ; longeur du dernler tour. p:ir rapport il I’ensemble 35/100; :iiiglr wtural, 89”. Coqullle allongCe, turrlculfe. Spire form& d’un angle r&ullw, conipoSee de tours ronvexes, ornPfi en travrrs, i~In drrnlfre rerolutlon splrale, de dlx cOtes flexuensw. ondulkn. non arr@t&s. sr correspondnut obllquement d’un tour a I’nutre. Sur RCR cBtes vlennent fie vrolser de leger8 ~Illou8longltudl- nnux treblnegaux. Bouche ovale, prolongee en avant et termlnQe par un sinus: lnbre trffi-(.cli:inc-rQen arrlfrr, s:iiIl:int nntCrleureinent.

HORIZONAND inrAi.rTy : Aptlen. C.rnnpe-:in-Itri. imr tlw Vnrln brldpr. rani. ~uunede WaRsy (Haute Jfnrne).

ReafARKf3: This fiprcies hafi volution!: of n roiinded outline, ri8fi continuous across thr wliorl and numrroiis 5pir;ils of different nrdrrs. It thus a simple shell, having the characteristic8 which might he eypected in an early typr of true Cm‘thium. A specimen in the !dufieum of Com- parative Zoiilogy doe8 not show thr young stageR, hut on the lafit three volutions two of the Rpirals are stronger than the others. This suggests the beginning of the development which hecomee a characteristic feature of Cerithium aquivpirule and later fiprcies of the genua. A posterior tooth is not devrlnprd on the inner lip, but thiR would hardly be expected before the spirals have become Rtrnng on the body 80 AXNALS A'h'IV J.ORK SC.4UEdlY OP SCIENCEB

volution, for the presence of such a tooth appears, in many cam, to be due to a strong spiral on the body volution, which projects into the aperture and is accented by the passage of the callus over it. Al. Cossrnann refers tliia species to Atresius, but in the description of that genus, the beak is said to be large and bent backward and the spire to be ornamented by nodulose cosk, characteristics which do not appear on this species. It seems to bear little resemblance to the type of the genus Atresius. Centhiurn albcnse d'0rbigriy

1842.184:i ('withiurn olbenw ~'Oaniox~.Pulbntol. Francnlse. Terrains Cre- tach. 11. Crust~ro1mdes.1). 3.55. pl. 227. flgs. 10-12.

The original description is as follows:

DIMENSIONR:Ooverture de 1':inple spIr:il. 20' ; longrur totale, IS mllllm.; dl:iiili.tre. 4 iiillljnl. : longeur du drrnler tour. par r:ipport a I'ensemble, 30/100. (hqujlle trPs-:illon&. nc.l(wl6e. Splre fornifie d'un angle r6guIler. mmpos& cle lours ~onveses.s61):irh pair dw suturm. ornGs. en long, de cotes Inegnles, tiont c1u:itre. ~IUR,yrosses. plus witII:~ntex. tr:inebantes. vont dlmtnuant de grosseur des suNrleures aux InfWeures. Entre chocune de celles-cl exlste une petite cote tres4trolte; 11 J a encore. en travers, par revolution splrale, dp onze ou douze dtes orroildies. tlroltes. sur lesquelles passent lea preml8res. IR dernler tour a de plus une seule cote longltudlnale. Bouche ovale. pro- long& en wn:il, 131 avant. Lnbre inlnre, trnnrlinnt.

Ilonrzon AND IBCAIJTY : Neoconilan. Mnrolles (Aube). Frnnce.

REMARKS:The figures of this fipecia show a simple type of shell with rounded volutione, well-developed rib8 and three strong spirals on each volution. A finer fourth spiral is also present jugt below the suture, and the ~liellIR further ornamented hy a single intercalated spiral between each piiir of the coarser ones. The outcr lip ha8 the crenulated margin ChilractPrifitlr nf ('. nqi~kpirnlrant1 later specairs of Perithiurn. This Rhcll is simpler than C. c.ornurhnrrrn in pnsses"Rng two orders of fipiral~only. ;in(], fin far as c.an 1w drterrninc(1 witliciut an examination of the shell, it swins t(t c.onPtitutc~:in rarlivr III(VIIIW~ of the f'erithium line of evolution 81

The original description of this species is follows :

Coquille turricul&, ellong&. 9 &es longltudlnnlen. tcu iiouhre de clnq 8ur IPS tours su[&Ieurs. mais plus IloUlbreUS~Ssur leu autres; ellen sont recoup& par des sjlloiis tr:iiiswrsw :IU noiuhre de truis siir chayue tour. Eouche ovale. aiigulruse suIi6rlrureuieirt. kli:incrure 1:irge. profonde et olilique.

I~KJZOX AXU IUC'ALITY : Jurassic. ('orel-rag. St !dIchIel. France.

HWARKS : l'his species of C'eritlrium shows primitive characteristice in its siinple ornamentation consisting of primary spirals and ribs only, 11s iiioderate t1egrc.e of embracing of the ivhorls and its ~impleaperture, with short, straight canal. The points of intersection of the spirals and ribs are often elevated, giving the surface a nodose appearance, hut the ornamentation is composed essentially of the ribs and three simple spirals 01i1v. In this respwt the shell is invre primitive then C. albense and must resernhle the young of that species before the introduction of intercalated spirals. Specimens of this species were not obtainable, but froni the evidence furnished lip thc literature it erems to I)c an ancestral form of f'rritlrii~n and the earliest representative thus far obtained of the line of evolution terminating in C. tuberosum. This species has heen referred to the genus BrarhIyttema. hut a com- parkon with thr tvpe of that gemis, R. hiivignler'i, Rhow a wide contrast in form and ornamrntation, the Iattcr Fpecies having the low +re and wide apical angle of the geniis Tmdtrrs, with the outer lip much expanded and the body voliitinn Ionper than the remainder of the hell.

v. SUMMARY 82 .J.VMJLS NBlV 1.01U AC'ADEM 1' OF SCIBSCES oped by the addition of a third spiral above the two prilnary ones. Such a type of development is epitomized in three species of the upper Eocenic. c. bica7inalum has adult ornamentation like the supposed prirnitire an- ceator of c. cosullense-that is, two equal spirals crossed by ribs (plate IV, fig. 9). The immediate descendant of the former species is C. bicasi- mtum mut. trispirule, a form which corresponds with C. corallense in having a third spiral present above the two primary ones, producing a shell with rounded volutions and an ornamentation of three simple spirals crossed by ribs. The lower Cretacic species, c. dbcnse, show an advance upon c'. corallense in the introduction of intercalated spirals, and it has its parallel in the Eocenic species, C. retardatum., which differs from its immediate ancestor, ('. bicarina/uni ]nut. Irispiralr. only in the presence of intercalated spirals. C. bicarinahim is descended from an early ancestor of Cerithium., and is so retarded as to retain its ancestral characteristics nearly unchanged. Its descendants pass through rapidly, in one geological period, a path of evolution which has been traveled more slowly in the main line of evolution from early ,Jurassic, or possibly Triassic, to Cretacic time. An advance upon the t\pe of development shown in C. albcnse is seen in t. f~rn~c~~n~~,of later Cretacic (Aptien) time. This fihell has many intercalated Rpirals, and two of the primary spirals are stronger than the others, forming a slight projection around the median portion of the adult volutions. This projrction, although similar in form, is not the derelopmc~ntal equivalent of the primary two-spiraled stage, for in thr phylogeny of the genus it appears after the fitage with thrre prirnarv spirals and aftcr the drvelopment of intercalated spiral!:. 1 n rccrnt, highly acceleratrd Fpecics of the genus, intercalatcd spirals appear so early in the ontoKeny that the !:tap with three simple spiral9 iR either omitted altogefhrr or obscured by the fad that the third spiral on the shoiilder never IlrclomeR as strong as the others. In fiurh caws the ctage just descrihrd srrms to hr rontiniioii!: with thc primitivr twwpirelcd stagr, from which it diffcw mnrphnlogirallv only in the prrsrncr of intercalated !:pirals.

Thr grratrr ahiindnrlw ,jf Errcwir matrriel in thr rollrction8 ptiidird f1imisht.s an oppnrtiinity for drtermining the phrlogrnv with greatrr crrtainty then in thc rerlicr hnrizon!:. At that timr p. nqiii~pirnl~rpp- resrnt8 the nrxt stage in thr phvlogmy of the gmiis hryond P. c07n74e- Iianvm, for on thip ppwimen the two rqiial spiral!: arr ncII drvr1opc.d and prrsi!:t to the adult whorlQ. and cpirals of crrrral nrdrrq are easilv rrcop- nizahlc. Thc vniinp ctapru of I' mq7ii~pirnl~arc rinfnrtiinatrlr missing. but they were doubtless simpler than the youngest stage preserved, and were probably not unlike the young specimens referred to C. imbsolu- tum; but if these specimens are correctly idenified, the adult diffen from c'. ruyuisptrult: in the direction of' IOSS of fine spirals and of the shoulder. C. lamellosum carries this loss of ornament still farther, and the two constitute a lateral branch in the phylogeny of Centhiurn. C. calcitra- podes represents another lateral branch, having its young stages like the adult C. cornuehnurn, but its later stages have a shoulder with a sharp angle of the type seen on recent species of the genus. As stated above, the European Miwenic and Yliocenic furnish no un- doubted species of Cerithaum sens. etr., but in the Miocenic of Florida C. thipolanziin seems, so far as can be determined from the description and figure, to belong to this genus and to represent a branch in which a comparatively low spire is developed. C. chipolanurn is probably an American representative of an undescrihed European form which was the ancestor of the somewhat low-spired recent species, such as C. adunsoni, C. cclrinatum, etcetera. The Pliocenic C. callisom has the high spire characteristic of the type #If the genus C. tubertisum, and it, too, probably had its European par- dllel, which aas the ancestor of C. iubcrorum and other high-spired related forms. The abundance of material in the collections of recent shells reveals a great flowering out of the genus in recent time, and however different the appearance of the adult shells, all reveal their common anceetry by a similarity in their young stages, as described above and indicated on plate I. Among the genera closely related to ('erilhium, Vulgocerithium is perhaps the nrsrest, developing aa it does at an early stage the two Rtrong spirals with intercalated spirals, and diverging from the main line of evolution only in the greater development of nodes and in the nbscnce of A sharp shoulder angle in the adiilt. Species of this geniis serm to undergo little chanpe from Oligorenic to recent time, and all the species described are similar in aenrral apppariim'r and differ from one another only in details. 'rhe geniis PolnmIdvs ir; CII)FPIVrvlaf4 itJ C'erithkn. The 1) pe IJf the gmus P. laniatcki develop the hicannate ornamentation in the same

nianncr aR in C. rptardnfuni (plwti, iii, firs. 9, 10, and plate 117, fig. 9) or other retarded nr prirnitirr spwies of Cerithhm. but retains each $tap for a prcstrr portion of tlw spire. or, in othpr mtirda. if8 carlv on- tngenv is like that of Crrithim hiit rnnrr retarded. The adnlt rxpresw it9 divergence from Crtithiirn ti! ihelnping nodrs as the chief feature of its nmamentatinn. Afi pointed out almve, PotomidPn i.1 a more primitive pcniis than ('crithrirm in IIP ~lightlvdevelnprd (.anill. in the S~III- at .lXS.4Ls’ XEH: 1.011K ACdUEUY OF GCIENCES I plicity of its ornamentation and in its retarded ontogeng. It is probably developed from the mme bicarinate ancestor from which Cerithium arose, but includes primitive types which persist throughout several penodt, of geological time. Ewenic species of Potailaides foriii, like Vulgocerz- thium, a compact group the members of which do not diverge strongly, even in the adult stages. The genus Tyinpanotonus is founded upon J1uze.c fwcatus LIKN~.a species formerly referred to Potamides, and thls shell has the typical Potamides young stages, forming the pwuhar ornamentation of the adult by developing its median row of nodes into large spines. ‘I’he genus should I,e restric~lto those forriiv which are like I’ola.midea in the young and only show divergence in the neanic or adult stages. As thus restricted, the genus is a direct descendant from Potamnides. The genus f’otarnidopsrs, having for its genotype Ce72thium tricarinatum LAMAECK,is also closely related to Cerithium, as shown by the development of the genotype. This species forms a bicarinate ornamentation in the same manner as both Cerilhium and Potamides (compare plate VIJ, figs. 7, 8, with plate 111, figs. 9, 10, and plate IV, fig. 9), but it is more accelerated than Polamides. Beyond this stage, Potamidopsiv diverges strongly from Ceritkiuna in forming its shoulder angle just above the suture and in having its surface ornamented by rows of nodes. The genus as a whole is less accelerated than Cerithivm. As a probablr ancestor of P. tricarina.ta wc have P. ac11s. whose adult stages rrsemhle the ninth to the thirteenth volutions of P. tricarinata, and from this specie8 we have developed P. zoissyi and P. tu.bcrrulo,su, whose development is parallel to that of P. tricarinala up to the P. aclls stage. After this stage thew forms diverge from P. tricarinah hy developing the uppermost instead of the lowest row of ncdea. The ancestor of (’withiurn immcdiat.elv preceding the Jurassic sprcieq described prohahly possessed a bicarinate ornamentation cromed by ribs and a verv slightly developed canal. The young stages probably had roiinded whorls, with one spiral at first and later two continuoils spiral*. The collections thw far Rtudied do not fiirnieh fiiifficient evidenw for a

Rtatrment as to the canalless form from which this primitive ancestrtr tjf the gem8 WBA derived. CPrithiiim is a grniil; whwh fihowr R strong trndr1lr.v to van. a:, dIl,,r.,, bv thr peat divemiti. of forms prewnt in the Eorcriic. art11 still grwter variety in recent timr ; hut, notwithstanding the wide diffrrmcw 111 adults. relationship mar hr trared hv Rimilaritr in thr roung stap, pointing out the path of mhtion which all have travvIPd i I! I:

3: I giL

\-2 '! I c

-. -:- 3 . ~ 5 LITEMTUBE

AUANS.C. U. . Catalogue of 1’:iii:iua Shellw. 1852. ADAXSON.Id. : Histolre Suturelle du SCuCgal. Arec le Belatlon abrlgfk d’une Voyage falte en ce pays, pendant les annfks 174463. Park 1767. YON ALTU, -4. : Die Verstelneruugen des Nlznlower Kalkstelnes. Beltrilge zur 1’:iliiontologie und Geologle osterrelch-unguriis und des Orients. 1. I and 2 Thell, Heft 111 and IV. 1S82. D’.iRCliIAC, ET HAIME. Juwe: Descrlptlons des anluiaux fosslles du groupe nunilnulltique de l’lnde. IW3. ABXOLD. RADII : Xew and Chararterlstlc Species of Fossil Mollusks from the 011-barlng Tertlary Fortwittons of Southern Callfornla. Smlthsonlan Miscellaneous Collections, XXXII, pi,. 525-5463. June, 1907. Asciim, EME : Ijie Gastropodeii. Blvalven und Brachlopoden der Omdlschter Pchlchten. IWt rlige ZUP 1’:iliiontologle und GeoloKfe Osterrelch-ungarns umd des Orielits. Hd. XIS. 1WG.

86 ANNALS A’BIV YORK ACADEMY OF SCIENCES

LITWTUEE

ADAM&C. B. : Catalobue of P$inarua Shells. 1852. ADANSOX,31. : Hlstolre Xaturelle du Senegal. ATW le Relation abrlg& d’une Voyage falte en ce pays, pendant les annM 1749-W. Parla 1767. YON ALTH,A, : Die Versteinerungen des Nlzniower Ktllkstelnea. Belwe zur Palbntologie und Geologle Bsterreich-ungarns und des Orlenta, I, 1 and 2 Thell, Heft I11 and IV. 1882. D’ABCHIAC,ET HAIME,JULES : Descrlptlons des anluiaux fosslles du groupe nummulltlque de 1’Inde. . 1853. Amom, RALPH: New and Chnracterlstlc Spedes of Fossil Molluska from the Oil-bearing Tertlary Fonnatlons of Southern Callfornlo. Smlthsonlan Bllscellaneous Collections, XXXII, pp. 625-646. June, 1907. ASCHEE, ELSE : Die Gastropoden, Blvalven und Brachlopoden der Qrodlschter Schiehten. Bejtr8ge zur Pslaontologie und Geologie (Isterreich-ungarns und des Orlents. Rd. XIS. 1908.

UABBOIS,CHABLEE: MCmolre sur le Terraln Cretace des Ardennea et dea r6- glons volslnes. DE BASTEROT,11. B.: Descrlptlon des coqullles fosslles des envlrons de Bop desux. Unlvalves. Jleniolre de Is Soclete d‘hlstolre naturelle de Parls, 11, pp. 17-100,PI. 1-7. 1825. BAYLE:Note ghloglque eur les provlnres d’Ouran. Bulletln de la Soclete ghloglque, XI. 1854. BELLABDI,LUXGI E h11crmm~~1,CIOVANIU : Sagglo orlttograflco sulla ClnSEl del jpstropodi fossil1 dcl terrenl Terziarll de Plemonte. Torlno. Exts. Menlotre della Henle Accndernln delle Sclence dl Torlno, Serle 11, Tom. 111. 1840. BEYBICII,E. : Dle Conchyllen des norddeutschen Tertlllrgeblrges. Zeltachrlft d. Deutsch. Geolog. Gesellscliaft, Bd. V. 1852. DE BLAINVILLE: Dlrtlonnalre tles sclences uoturelles. &iotlusks. ISZO. -: Fauna Frnuyalse. Mollusks. 1825. BijaM, JoriaNNEs : Dle G:isteropaden de8 Mnrmolntnkalkes. Paloeontograph- Icn. SLII. 1m5. -: DIe Kreldelilldungen dcs FIlrberpR und Sulxbergs be1 Selgsdorf In Ober- bayern. Palmntogaphlco, XXXIII. 1891-1802. I~ROCCI~I,Ih 0. : Conclilologln fosslle subnppennlna. I I, Mllano. 1814. BROILI,FERDIXANI) : Die F:mm der Pnrhycsrdlentuffe des SeIser Alp. Seaph- opndeii niid (hstropoden. Pnl.mntogrnphlra. LIV. 1!IO7-1908. TIROROKIART. J\I.EXA~~RE:Wniolre sur len terrnlns d’eau doure. Annales du MusFuni Sntlonnl d’hlstolre nnturelle, XV. 1810. Baoxx. 11. 0. : Index pnI.mntologlcus. 1848. ~: ltnllenn TertlBrgeblIdc. 1&U. TIEOWN, Tllobras: Illustrntlon~of the Fossil Conrhology of Great Brltaln and Irelnnd. SOR.1-1s. 3%?4-18%% RRIYW~RE: Hlstolre nnturelle den YerR. EnryclopMle hlethodique. Tome I. pt. 2. pp. 345-758. 3792. 1~I:vrosIER:3fFniolre silr qiirlqae~fonRlles nouveau des dapnrtments de la Meuse et drs Ardennes. M(.iiiolw cte In SoriFt6 Phllomatique de Verdun. 1843. WOOD, PHYLOGESY OF CB11T.4IA‘ C’ERITHIIU& 87

CHEW, J. G. : Manuel de Conchyliologlc. 1. pp. ?i9-284. 18‘3. CAJLUMNIE’ABII : De aquatilibus allisque uonnullis animallbus. Roma. 11316. COSSMANN, B~AUEICE:Contributlon & la I’nlbontologie Franenlse des Terralns Jurasslque Alh. de lu soc.16te gGologique de Frnnce, No. 14, V and VI. PIS. XVI-xx. 1m5. -: Catalogue illustre des cquilles fossiles de I’Eocene des environs de Paris, Appendice KO. 3. 1W2. IbM. Quatrieme fascicule. CoSSBfANN, hlAUEICE, ET PISSARo. (3. : F:lUIle fiW€!nlqUe du &tenth, 1903. I. 11. Bulletln de la Societe Gbloglque de Sormandle, XXII, pour 1902, publie October, 1903. C~JSSMAX,MAUSICE : Observations sur Quelques Coquilles Cretaciques recuell- lies en France. 18%-1903. -: Essais de Palhnchologie Conipark. Peptieme Iivmieon. Juillet, 1908. DAINELLI,G. : I1 ltflocene Inferlore del Monte I’romina In Dalmaxla. Palzon- tologla Itallca, VII, 236-285, pll. 29-33. 1901. -: La fauna eocenlca dl Briblr In Da1m:izla. Palmntographlca Itallca. XI, pt. 11, 1-91, ~11.1. 2. 1905. DALL,Whr. REAI.Y: Contribution to the Tertiary Fauna o! Florlda, with especial reference to the Miocene Sllex-beds of Toinpa, and the Pllocene beds of the Cnloosahatcliie River. Trans. Wngiier Free Institute of Science of Phlladelphla, 111. pt 1. August, lB!H); pt. 11. December, 1892. -: On the Synonymic IIistory of the Genera Clam Martyn and Cerfthitrrn Rruguiere. Proc. Academy Natural Science Phlladelpliln, AupIst, 1907. Issued Septeiiiber 28, l!lO7. DAUTZENBERO& DOLLPUS : Mollusca. Itousslllo~~I. 1882-1885. DEFRANCE: Dlctionnaire des Sciences Saturelles. VII. 1817. I)ERINOEB,RABL : Dle Gastropoden der Sirhslschen I

IClcHWALn. E. : S:iturhlstorisrhr Sklzz~VI~ I.lthallen. Volhynlen und I’odollen. 1830. -: IAhm Rosdra. 1853. ETALUJX: Etude pnlhntologlque sur Ir Jurn Erflglols. MernolreR de la Soclete d’Eniulntlon du DouRs. TrolnlPinr sPrle. VII I. 1862.

FIRCIXER.PAUL : 3fannel dc Coii~~hyllologie.1M7. 88 ANNALS NEW YORK ACdDEdlY OF WIENCES

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HABBIB,G. D.: Newene hlollusca of Texas. IMletln Amer. Pal. I, No. 3. De- cember 2. 185. -: The JIldwey Stage. Bulletln Amer. Pal. I. No. 4. June 11, 1890. HAIIEIB,0. F.: The Australnslnn Tertiary Molluscz. Brltlsh Museum Cata- logue of Tertlary Xolluscn, pt. I. 1897. IIABBIB,CEO. F.. and BCBBOWS,HENBY W.: The Eocene and Ollgocene beds of the Park Rash. Geologlst~’Asmlatlon. Imdon. Aprll 3, 1891. HEIIZRIN, AN~EIB:Explorntlons on the West Coast of Florida and In the Okeechobee Wilderness. Transactlons Wngner Free Instltute of Science, Phlladelphla, I. May, 1887. HOLZAPFEL, E. : Dle Mollusken der Aacliener Krelde. Palreontographlca, XXXIV. 1888. 1IOblnRON ET JACQUES: Voyage Astrolabe Zoologlque, v. lE(33. Iliinms. MOBITZ URD PABTBCH,PAUL: Die Fosrtllen Mollusken des Tertlltr- 13wltrnr, ron Wlen. Abhandlungen der kal~erllch-kanlgllchengeologlachen Iklrhsnnstalt, nand 111. 18556. H8RNER. RVDOLF: Neue Cerlthlen aus der E’orinengruppc der Claua btdentata (Herr.) Grntejoup ron Olsnltz In Jllttelstelrmnrk. Sltzungberlchte der lll~thrrll~tI~~lir-~iatur~I~~ln~rhnft~~chenRlnsfie der kalserllchen Akademle der Wlssrnsc~linftrn. R:ind CX, Abh. 1, TIrft I, pp. 316344. 1001. IJiiRnrm. 11. c‘xn AVINOER.11. : Dle Gnstropodcn drr JlrereRablagerungen der rrwtrn und zwrlten niloc4nrn Jfedlterrilnstufr~. Vienna, 1879-92. HI.nLE8mN. Wr.Fain 11. : A Jlonogrnph of the lnfrrlor Oalite Gasteropoda. I’t. 1. The I’nl:ir~nto~r:iplilt.nlSorletg Jfnnogr:i]ilis. 1887-18M. I~TATT. AI.PIXEUA: OPIWRIRof thr Ar1etld:v. Smlth~onlan Contrlbutlone to Knowledge. No. fX. IRX!). WOOD, PEYLOQEYY OF CERTAIN UERlTElIDI 89 Kxsslrao, E. : Die Fauna des 3Iittel-Ollgocllns Im Berner-Jura Abhandlnngen der schwelzerlschen paltiontologlschen Gesellschaft, XXII. 1895. KLIPBTEIN,A. vori : Mltthellungen aus dem Gebletete der Geologle and Palseon- tologle Band I. Beltrtige zur geol. Kenntnlss der 8etl. AIpen. 1843. KOBELT,WILL : Die Gattung Cerithlum in Systematlwbea Conchyllen Cabinet van Martin1 und Chemnltz, Band I, Abthellung 26. 1898. KOENEN,A. VOB: Dle Gastropodo Holostolnata und Tectibranchlata, Cephn- lopoda und Pteropoda des Norddeutschen Mfodln. Neuea Jahrb. far Mlo- eral. Bellnge Band 11, zmeltes Heft, 1882. -: Das Marine Mlttel-Oligoctin Sorddeutscblands und seln Mollusken- Faunn. Pahntogmphlca, XVI, pp. 53-128 1867-68 KOKEW,E. : Dle GastroQoden der Trlas Hallstaat. Abhandlungen d. k. k. geol. Reichsanstalt Wlen, 18, Heft 4, 1897.

LAMABCK: Prodrome nouv. class. 1799. -: Systeme des anlmaux sans vertebres. 1801. -: Sulte des memoires sur les fosfilles dea envlrone de Parls. Annalea do h&um National d’hlstolre nnturelle de Parls, t. 111. 1804. LrriK, H. F. : Beschrelbung der Rostock Snmmlung. 1807. LrririIl, CABOLI: Systema Natum, Tomus I. 1767. LOBIOL, P. DE: Monographle PalEontologlque des couches de la zone A Ammo% fles tenutlobotus (Badener Schlchten) d’0berbucheItten et de Wangen (Soleure). Memolres de la Soclete Pal&ntologique 8aIaee, VII. 1881. -: Etudes sur les Mollusques des couches coralllgenea de Valfln (Jura). M6molres de la SocIBtB PalEontologlque Sulsse, XIV. 1887. -: etudes sur les mollusguee des couches coralllg&nes Inf6rleurs dn Jnre Bernols, Pt. I. Abhandlungen der Schwelzerlwhen Palliontologlachen Gesellschatt, XVI. 1889. -: Dmrlptlon de8 Mollu~queset Brachlopdea des Concha Beqnanlennea Memofres de Ia Soclet6 PalEontologlque Sulsse, XX. 1893. -: Etudes sur lee Mollusques et Brnrhlopodea de 1’0xtordlen sup&leur et moyen. Abhandlungen der Schwelzerlschen palllontologlwhen Geaellschaft, XXIII. 1m. -: EtudeR sur lea Mollusques et Brachlopodes de I’Oxfordien Int6rlenr on zone ll Ammonffeerenggert du Jurn Bernols. Abhandlungen der Schwel- zerlschen palllontologlschen Oesellschaft, XXVI. 1899. -* . etude Bur lea Mollusque8 et Brnchlopodes de I’Oxfordlen wperleur et moym da Jura BernoIR. Ahhandlungen der SchweIzerIachen palRontolog- ischen Gesellschaft. XXVIII. 1901. LOBIOL P. DE, ROYEB,E,, TobmcK. H.: Descrlptlon ghloglque et pal6ontolo- glque de8 Btngea jurasslque sup6rleure de la HauteMarne. MBmolres de la Swl6te Llnn&nne de Normnndfe. 1869-72, XVI, 1872.

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MABTIN,0. C. : Margland Geologlcal Survey Aiiocene (Alollusca), pp. 131-2iO. 1904. MAETIN, I(. : Dle Tertfarschlchten nuf Java. Palseontologlsche Thell. 1879. MAETYN, TEOMA~: The Unlversal Conchologlst London. 1784. MACBY, CABWTTAJ.: A Compnrlson of the Ollgocene of Western Europe and the Southern Unlted States. Bulletln Amer. Pal. 111, KO. 15. June 16, 1902 A~ELLEVILLE, Bf. : hfemolre sur les Sables tertlares lnferleurs du bassln de Paris, avec la descrlptlon de 78 esp&es de coqullles fosslles lnedites de ce terrain, pls. I-X. Annales des Sclences Gblogiques. 1843. B~OXTFOBT, D. DE : Conchyllologle Systeniatlque 11. 1810. AftiRaTEB, GB. zu: Beltrllge zur Petrefactenkunde, IV Heft. Beyreuth. 1841. A~USCHISON, R. I., DE VEBNEUIJ.,KETSEBLISQ, ALEX.: Gblogle de la Russle d’Europe et des Montngnes de I’Ournl, 11, Pt 3 Pnlbntologte. 1845.

NEWTON,R. B.: Systemtlc Llst of Brltlsh Ollgocene and Allocene Bfolluscn. 1891. NOETLINQ,F.: Dle Fauna der haltlscben CenomBn-Geschlebe 11)o Tnf. XVI- XXIII. Palmntologlscbe Abhandlungen, 11. 1884-1885. -: Fauna of the Upper Cretnceous (laestrlchtlen) beds of the M8rl Hills. Memoir of the Geologlcnl Survey of Indla. ser. XVI, vol. 1, Part 111. 1902. NYGT.1’. H.: Description des Coqullles fosalles des Terralnea tertlsre de la Belglque. 1843.

OLIVI: Zoologln ndrlntlcn. 1792. OPPENIIEIM,PAUL: Dle Eocilnfnuna des Monte Postale be1 Bolca Im Verones- Ischen. September, 18W. Tnfeln XII-XIX. Pnlmntographlca XLIII. 18981807. -: Dle Prlabonaschlchten und lbre Fauna, mlt 21 Tafeln und znblrelcben Flguren In Text. Pnlmntographlca XLVII. 1900-1Wl. -: Ueber elnlge alttertlare Faunen der Osterrelchlsch-ungnrlschen Yon- orchle. Tafeln XI-XIX, pp. 185-277. Belt. PBI. und Geol. Bsterrelcb- ungnrns und des Orients, Rd. XIII. 11)Ol. D’ORBIONY.ALCIDE : Pal6outologle Franqnlse. Drscrlptlon des Mollusgues et ItnyonnCs Fowlles. Terrains CretacEs GasteropdeR. XII. 1842-1843. -: Prodrome. 1850.

PAUTBCR.PAUL: h’cue Aufat. der Petrefaktenkundc. Smmlung des k. k. hflneralog. Cab. in Wen. 1842. PEASE,WILLIAM HABPEB : Deserlptfons of New Specfes of Marine Gasteropdn lnbabltlng Polynesln. American Journal of Concbology, V, pp. 04-87. 1870. PIiII.IpP1, R. A. : Enumerntlo hlollu~coruniSlclllne, I, 1830; 11, 1844. -: Tertlllrverrjtelnerungen drR nordwestllchen Deutschlnnds. I%?. -: Abblldungen und Beschrelbungen neuer oder wenlg gekannter Conchy- Hen, 111. 1851. -: Verzelcbnlss der in dcr (;%end von hfagdeburg aufgefundenen TertlHr- verstelnerungen. Palmntogrnphlcn. 1. pp. 42-90. 1851. -: Die tertlLrrn und qiinrtilirrn Tcrfiteinerungcn ChlleR. Lelp~lc. 1887. Puscn : Polen8 Pnllontolopie. 1%7. WOOD, PHYLOGENY OF CERTAIN CERlTEllDB 91

QOLVSTEDT,FFLIEDBICH AUOUST: Petrefaktenkunde Dentschlands. 1st Abtellung. slebenter band. Gasteropoden. 1881-1884.

REEVE, Lorn AUQO~TUS:Conchologln Iconlca, or Illnstratlons of the Shells or Mollnscous Anhnals, XV. 1866. R~sso:Hlstolre naturelle des envlrons de h’lce et des Alpes marltlme, IV. 1826. REHBINDEB,B. : Fauna und alter der Cretacelschen Sandsteln In dle Umgebung des SawBaskuntschak. Xemolres dw comlte gMoglque de Rnsale. XVII. 1902 ROISSY:Hlstolre naturelle dea Mollnsques, VI. 1805. ROYAXOWSKI,G. : Geologlsche und palllontologlsche Uebemlcht des nordwest- lichen Thlan-Schan und den sUd6stllchen Thelles der Nlederung von Turan. 1880.

SAXDBEBOLB:Untersnchen Uber das Malnzer Tertlgrbecken. 1853. SCHLOSSEB,MAX : Die Fauna des Kelkelruer Dlcerns-Kalkes. Palseontograph- Icn. XXVIII. 1881. SEBBES, MABCEL DE: Essal pour servlr 8 I’hlstolre des anlmaux dn mldl de la France. 1822. SHEBBOBN,C. DAVIU, and WOODWARD,B. B.: On the Dates of the “Encyclo- Wle Methodlque” (Wlogy). Proceedings Zdl. Soclety London, pp. 682- 684. la. SIeafoNoa, E. : Sgnopsls rnethodlque anlwnur lnvertebres Fed. loss. 1847. SOWEWJY,C. B. : Theenurus Conchyllorum. or Monogrnphs of Genera of Shells. Edlted by 0. B. Sowerby, 11. 1855. SPEYEB,OSCAB : Die Conchyllen der Cnsseler Tertllrblldungen. Palreonto. grnphlcn. XVI. 1866-1869: XIX, 1871. STANTON,TIMOTHY\ W.: The Colorado Foruntlon nnd Its Invertebrate Fnunn. Bulletln U. S. Geological Survey, Number 100. 1893. SIWLICZKA,FEED.: Gastropods of the Cretnceous Rocks of Southern Indln. Memoirs of the Geologlcal Survey of Indln. wr. I. rol. 11. 1868. BTBUCKMANN,C.: Neue Beltrllge zur Kenntnlss des oberen Jurn und der Wenldenblldungen der Umgegend von Hnnnover 6. 3 Tnf.. I-V. Pnlllon- tologlsche Abhnndlungen, Erster Band. 1883-1883. STURANO,RUDOLF: Gastropoden dw Rothen JIeerea. Erpedltlon 8. bf. Schlff “Poln” In dns Rothe hleer. 1895-96; 1897-9S. Denkschrlften der knlser- Ilchen Akademle der Wlssenschnften. Band 74. 1904.

TBOSCHELF. A. : Dne Geblss der Schnecken. zur Begranden elner naturllchen Clnsslflcatlon, I. 1856: 11, 1878. TRYON,Gmm~ W. : Manna1 of Conchology, IX. 1887.

VINASEADE Reurar, P. ffi: Synopsls del mollu&l tenlsrl delle Alp1 venete. Pnlmntognphlcn Itnllcn, I. pp. 211-!275, pl~.XVI-XVIII. ISW (for 1896). pp. 149-184, pls. XXI-XXII,1897 (for 1896).

WANNEB.J.: Dle Faunn der obersten melssen Krelde der llbyechen WUste. Palmntographlcn. XXX, pt 2. 1902. 92 ANNALB NEW YORE AOADBMY OF KOZllNOEK

W~B,0. : DIe Fauna dw Neocomsandetelne lm Tentoburger Wald 6. 3 Tat, I-XI. Paleeontologische Abhandlungen. Band IL lB4lSS. WEIDBOBRE,0. F. : A Monograph of the Devonlan Fauna of the Wuth of Plng. land (1891). The Pahntographlcal society, London, I. 1889-1892. Worn, W~HV: DIe Fauna der sfldbayerlschen Ollgodlnmolnsae. February, 1887. Paleeontographlca, XLVIIL 1898~. WOOD,Swum V.: Monograph of the Orag Mollusca. Palaeontographlcal go. ciety Monographs, London. 1848. WOOD,WILLIAM: Index testaceologlcus, or a Catalogue of Shells, Brltlsh and Forelgn. 1818-1828

Zm,~~'~~EDEXCE: Dle Gastropoden der Qoaaogebllde. Abhandlungen der k. k. Wlen-Geol. Relchsanstalt, I Band, 1852. VON Z~L,K. A: Die OasteroAen der Stramberger khlchten. Palreonto, graphlea. Beltriige zur Naturgeschlchte der Vorwelt Supplement 1873. SLRYACE FEATURE8 OF (EHITHI~’LI ASIJ VL IiCOCEEITHlUM I I I I I I I I i I I I: I'LATE II

1;iti. 1. ~icircor.o,i/hifi~~fboftci I 1)esiiaues). '* 2. E'io. 2. Vicitioccriihirim parallcliiifi &p.nov. x 2. FIG.3. CertfAiuwt odansoni BEL!GUI~?RE,a young indivldunl. X If. Flu. 4. Cerilkiutu fccberosuin COLCbiNS. x 14. Fio. 5. Cerithiiim nqiiisp~ralePI). no\'. X 2.. Fla. 0. Cerithhni wfardofum 81). nor. X 2. Fie. 7. Cerifhftinr bicorinafiriti milt. trispfrolb mut. nov. X 2. Fio. 8. Cerfflriuni bicarinnfim rtEsllauE8. X 2. The flgures nre from photogrnphs. retouched by the author. 1

7 -1 I'LATE Ill

ohroti~~~OF SIX SPECIES OF CEBITHIUM

SUUIIWIY:it ill(, left or thc. pl:itc+ ltidic.:ite the numbere of the volntlona Ibtted lilies Indicate gr:idu:il tr:tiisltlon Proni one volutlon to the next figured. 'l'iie ;i~iiouirtof eiihrgetiieiit la glwii oir ilie phte; actual measurement of the lurtioii of tlie slrell tilured Is C.~II,II below. All the flguree on Platea 111 to IX ;ire fronr original drswlngs by thr outhor. - -c i

c c .a C c 0) 5: ------k ----; K I w 3 ir +0 E x

-0 m - h------

L, E’Io. 1. Cerifhiitm tubrt’osuni, eiglitli volutlon. 4.6 x 2.2 mm. Flu. 2. Cerifhlum adansont, flfth volutloii. 3.5 x 1.5 mm. Fro. 3. Cerithlun adonuont, eighth volutlon. 9 x 3.4 mm. FIQ. 4. Cerifhkmf nodulosunt. sixth volution. 6 x 3 mm. FIG. 3. Ccrifhiumf ttodulouum, eiglltli volutlon. 6 X 5 mui. Later whorls of thls shell 3re not flgured. :IS they are too large to shorn detalle when reduced to the scale of tht# plate. FIQ. ti. Parudot.crtagu8 atuco, seveiitli volutlon. 5.2 x 2.3 mm. FIG. 7. I’seudovrrfages aluco, eightli solution. 7 x 3 mui. FIQ. 8. Cerifhium lamellosum, Bfth volutlon. 1.2 x 5 mm. FIQ. 0. Cerithtunt relardalum, Bfth wlutlon. 1.2 x .5 mni. FIQ.10. Cerllhtsni rrtardatuni. seventh volutloii. 2 x 1 mm. '0 c

a P YIG. 1. Cerifhlirni adatrmii, ninth \olutloii 12 X imm. PIG.2. Cerflliurn adammi. aperture 16 x 12 mu. No. 3. Cerfthiuw crqrrispiralr, Iiiritli rolutioti. 2.5 x 1.4 mm. Via. 4. C‘erilliu?n crqrriq)itwla, t\relltli rolutlon. 4.4 X 8.5 mm. FIG.6. I’seudocertagus alrfco. tenth volutlon. 10 X 4.5 mm. FIQ.U. I’seudovertagus aluro, eleve11111volutlon. I0 x 7 mm. FIQ.7. Cerfthiuni lamellosutn, nlntli ~olutlon. 3.4 X 1.6 mm. FIG.8. Cefflhfif?ii /at/rrllosirttr, eleveiith rolutlon. 6 x.3.5 mm. FIQ.9. Cerllhfrc?t/r-clardat/fttc. rilnth tolutlon. 3.8 X I 8 III~.

PLAI'E VI

ONTUGENY OF SIX SPECIES OF CEEITHIUY (contlnued)

FlQ. 1. Cerithiuiu tubtrosuni. thlrteenth volutlon. 12 X 11.5mm FIQ.2. Cerifhdum tuberosum, fourteenth volutlon. 24 X 29mm. FIQ.3. Cerfthium cqulspirale, fourteenth volutlon. 9.6 X Oamm. FIQ.4. Peeudouerfaguu aluco, thlrteenth rolutlon. 19 X 11 mm. Fio. 6. Pacudovertagus aluco, fourteenth volutlon. 22 X 2Omm. FIQ.6. Cerilhium laniellosum, aperture. 12 X 11 mm. FIQ.i. Cerithium retardatum. fourteenth volutlon. 8.5 X 4 mm. FIQ.8. Certthfuni retardatum, :iperture. 7 X 9 mm. h 9

1210. 1. C’erithium t.al/isontu. tiixtli volutlou. 1.8 x .8mm. FIG. 2. terifk{unt eallisonia. eighth volutlon. 2.1; x 1 utm. Fio. 3. Ccritbiuin riicri/;ei, flftlr volutlon. 1.8 x 1 mrn. Fio. 4. Viciiiocc~rithirtrnpavu//r/iffn, flfth volutlon. 2.4 x 1 am. Fio. 5. I’icinocerithiunc parollalrrv~.seventh volutlon. 3 x 2 mm. Fio. 6. ~ici,ir,e~rilliiifr/ibouef, rlghtli volutlon. 2.8 x 1.4 urn. FIO. 7. Potonlidopsis Iricarinalrr, slrtli volutlon. 1.4 x .6 inm. Fio. 8. f’otattiitlopziu Iricuritiofu. tent11 rolutlou. 2.i x 1 ruin. Fio. 9. Potatiiitlopsis Irorhlrwc. slxth volutlon. 1.3 x 3 mm. Fio. 10. I’otumitlopaitr fndilratr rwelftli volutlon. ll.h x i.5 mm. d b

9 0-

U Jl PLATE IX

ORTWEITY OF CERITIIIIILE (contlnued)

Fro. 1. Cerithfum cdlkoma, tenth volutlon. 5.3 x 7 mm. Fro. 2. Uerithhm mnkei, tenth rolutlon. 13 x 11.5 mu. Fro. 3. Vkhocerlthfum parallelrni, twelftli volutlon. I; x 4 mm. Fro. 4. VWnocerUhhm paralleluni, aprtnre. 9.8 x 8 nim. FIG.6. Vlcinocerlthlum bouei. twelftli volutlon. 3 x 2 iiini. Fro. 0. Vldnocerlthfum Bowi, nperturr. 8.5 x 6.5 i~ini. FIO.7. Potamfdopeb trfcarfflofa.t\wnty-thlrd voliition. 12 X 5 mm. F1o.8. Pot~mfdopufutr(carina!u. t\vmty fourtli volutlon. 19 x 11 mm. Fra. 9. Potamldopsfs trochleate. aperture. 11.8 x 7.5 ium. 0)

C U 1" 0

N ry qI'AHHI I\ BAhAll Al WLLIT PATOBNIIN. N J