THE MIOCENE AND RECENT MOLLUSCA OF PANAMA BAY * BY CHIH CHANG Li lE ¿ INTRODUCTION The material studied has been in the Paleontogical collection, of Columbia University for several years. The label on the material reads as follows: "Brought up by marine dredge from depths varying from ro.. ft. to 4°. ft. in the mud at the mouth of the Rio Grande near La Boca about one mile from the mainland in Panama Bay." It was apparently collected by Mr. Donald F. Mac Donald in ro7, formly Geologist of the Canal Commission, and sent by him to Columbia University. The material has been partially identified by Dr. J. J. Galleway and Mr. S. W. Lowman in 1923. I discovered that this collection is a mixture of Lower Miocene and Recent shells, for the collector was unable to keep them separate under the circumstances. The faunas of the two horizons which are separated and the relative abundance of each species are as follows:- LOWER MIOCENE SPECIES A thesis submitted for the degree of M. A. in Columbia University. 249 i. A rca dariensis Brown and Piisbry a 2. Arco cf. pennefli Gabb r 3. Arca cf. piUceri Dali r 4. Arco (Scapharca) golfoyaguensis Maury r . Cancellaria harrisi Maury r 6. Cancelarla laevescens Guppy r 7. Cardium sp. r 8. Cardium parvulum n. sp. 9. Cletneniia dai-iena Conrad io. Codakia orbicularis Linne r ti. Conus imitator Brown and Pilsbry 12. Corbula silirost ris n. sp. 13. Corbula cf. collazica Maury r '4. Corbulaglyptan.sp. r Corbuta cf. siviftiana Adams a
Transcript
THE MIOCENE AND RECENT MOLLUSCA OF PANAMA BAY *
BY CHIH CHANG Li lE ¿
INTRODUCTION
The material studied has been in the Paleontogical collection, of ColumbiaUniversity for several years. The label on the material reads as follows:"Brought up by marine dredge from depths varying from ro.. ft. to 4°. ft. inthe mud at the mouth of the Rio Grande near La Boca about one mile fromthe mainland in Panama Bay." It was apparently collected by Mr. Donald F.Mac Donald in ro7, formly Geologist of the Canal Commission, and sent byhim to Columbia University. The material has been partially identified byDr. J. J. Galleway and Mr. S. W. Lowman in 1923. I discovered that thiscollection is a mixture of Lower Miocene and Recent shells, for the collectorwas unable to keep them separate under the circumstances. The faunas of thetwo horizons which are separated and the relative abundance of each speciesare as follows:-
LOWER MIOCENE SPECIES
A thesis submitted for the degree of M. A. in Columbia University.
249
i. A rca dariensis Brown and Piisbry a2. Arco cf. pennefli Gabb r
3. Arca cf. piUceri Dali r4. Arco (Scapharca) golfoyaguensis Maury r
. Cancellaria harrisi Maury r6. Cancelarla laevescens Guppy r
7. Cardium sp. r8. Cardium parvulum n. sp.
9. Cletneniia dai-iena Conradio. Codakia orbicularis Linne rti. Conus imitator Brown and Pilsbry12. Corbula silirost ris n. sp.13. Corbula cf. collazica Maury r
'4. Corbulaglyptan.sp. rCorbuta cf. siviftiana Adams a
250 Bulletin of the Geological Society of China
i6. Crassitellites rudis n. sp. r
17. Crepidula plana Say rIS. Cre/.'idula cf. plana Say r19. Distorlrix gatunensis Toula r20. Drillia zooki Brown and Pilbry r21. Drillia limonetta Olsson a22. Lucina cf. callozoensis Hubbard r23. Marginella cf. cineracea quadriplicata Böse a
24. Marginella evax n. sp. a2. Melongena tnengeana Dali r26. Metula cancellata Gabb r27. Myytaea linwniana Dali r28. Natica guppyana Toula a29. Natica youngi Manry a30. Osirea sp. r3t. Patella caliculus n. sp. r32. Pat ella calix n. sp. r
33. Pecten cf. circularis Sowerby r
34. Pecten filitexlus n. sp. r
35. Peclen (Amusium) luna Brown and Pilbry a36. Pecten reliquus Brown and Piibry a
37. Phacoids hispaniolana Manry r38. Phos costatus Gabb a
39. Pitaría acuticosirata Gabb r4O Pugna lobreana Maury r41. Palinices stanislas-meunie,i Muary a42. Solariam gal unense Toula r
43. Strc'tnbina elegans n. sp. r. Strombina laevistniata n. sp. a
45. Strombina tenuilineata n. sp. a46. Tellina cibaoica Mamy r47. Tellite costracana Olsson r48. Telling 5anamaensis n. sp. r
49. Tellina tenullinealus n. sp. r50. Terebra cracilenta n. sp. rx. Terebra gausapala laevifascila Maury r
The undescribed species are not easy to place in the proper horizon,because the Miocene fossils are well and beautifully preserved, nd most shells
of the two horizons- are equally fresii. I tentatively separate them upon thesecriteria; (x) species most closely resembling described forms, (2) the degree of
their freshness in comparison with other collections, and (3) by the range of
other species which were attached to the shells.
On application of the above criteria there seems to be little doubt theshells belong to two horizons, -Gtun formations and Recent. The number ofspecies of each group shows that the Recent sea mud does not extend verydeep, and that it lies unconformably on Lower Miocene.
Li: Miocene & Recent Moilusca of Panama Bay 251
52. Terebra gatunensis Ioula r
53. Venus ebergenyii Böse a
34. Venus walli Guppy a
RECENT SPECIES
i. Cardium parvulum n. sp. r2. Cardium procerum Sowerby a3. Cardium sp. r4. Crepidula plana Say r
5. Cre5idula cf. plana Say r6. Dr&liia inequisiriata n. sp. r
7. Olivacaliosan.sp. r8. Otiva cf. iliterata Lamark r
g. Ostrea sp. r
ZO. Pat tia caliculus n. sp. r
xx. Pecten circularis Conrad n. var. r
12. Pecten cf. latlauritusfucicobes Dali r
I3. Potamides neta n. sp. r
14. Psarn'nobia sp. r
15. Racla maxima n. sp. r
x6. Triton cf. bartheiemeyi Bernardi a
17. Tapes slaminea Conrad r
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SYSTEMATIC DESCRIPTION
PHYLUM MOLLUSCA
Class PELECYPODA Goldfuss
Family ARCID Dali
Genus ARCA Lamarck
ARCA cf. PENNELLI Gabb
Plate z, Fig. z.
Ai-ce pennsfli Maury, Bull. Amer. Paleo., Vol. 5, No. 29, 1917, p. ¡77, pl. 29, fig. 8.
Shell inequilateral, very oblique; amphidetic area wide; beaks distant,conspicuous; hinge line transversely dentate, with many small similar teeth;surface sculptured by 35 squarish plic with concentric impressed lines makingbeads ofthe plic on the marginal part of the shell.
Shell small, upper and basal margin subparallel, beaks small, at theanterior about one-fourth of the length of the valve; surface sculptured by 30squarish plic beautifully beaded by the impressed concentric lines; inter-spaces narrower than plic, marked' by fine concentric striations. Ligamentarea narrow, lanceolate, marked by two curved grooves.
Height, 12; length, 17 mm.OCCURRENCE: Gatun Stage, Costa Rica
HORIZON: Gatun formation.
ARCA DARIENSIS Brown and PiisbryPlate t, Figs. 3, 3a.
Arce dariensis Brown and Pilsbry. Proc. Acad, Nat. Sei. Philadelphia, Vol. 63, 1951
p. 302, pl. XXII, fig. ro.
Shell long, upper and basal margin subparal leI; beaks small, at theanterior two sevenths of thè length; valve slightly unequal, the left surpassingthe other along the basal margin; surfae sculptured by 31 radial, squarishplic; interspaces considerably wider than the pliese, marked by numerous fine,
Li: Miocene & Receni Molluca of Panama Bay 253
concentric lamell; toward the ends of both valves the plications widen andare divided by a median groove, on both sides of which the plic become
nodulose. Left valve closely nodulose at the lower part, short, scaly near thebeaks. Sulcus shallow; ligament area narrow, lanceolate, marked by two orthree curved grooves. Interior radially striate, the margins crenulate.
Sospha,ca goifoyaquensis Maury, Suit. Amer, Pako., Vol.5, No. 29, ¿9x7, p. ¿68, pl.
28, fig..
Shell inequilateral, oblique; lunule depressed; cardinal area sculptured by4iverging curved grooves; surface sculptured by 38 squarish plic, beaded byconcentric impressed lines; posterior broad and anterior narrow, hinge linelong, with numerous vertical teeth, oblique at both ends.
Height, 34; length, 49 mm.OCCURRENCE: Zone H (Lower Miocene) Ric Cana at
Caimito, Santo Domingo.HoRizoN: Gatun formation.
Family OSTREIDAE LamarckGenus OSTREA Linné
OSTREA, p.
Plate z, Fig. 5.
This is a young shell. it is small, thin and clongate, with variable out-line, broadly attached to sonte foreign body; the shell zr.argii bends abruptlyup at a right angle. The beak is obscurely denticulate.
HoRizoN: Gatun formation.
OSTREA, sp.Plate x, Fig. 6.
This shell is young, small, obscurely denticulated, wider than long, out-line variable, outer margin strongly upturned and sharply folded. The twospecimens are broadly attached to the recent Triton shells, and the margin..abruptly bends up at a right angle.
HORIZON: Recent.
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Family PECTINIDAE Lamarck
Genus PECTEN Müller
PECTEN RELIOUUS Brown and Pilsbry
Platez Fig. 7.
Pectea sp. (vielleicht n. si.) Toula, Jahrs. K. K. Geol. Reichsanat.. ¡908, LVIII, p,
755. text-figs. 12.,13.
Pecian reliquus Brown and Pilsbry, Proc. Acad. Nat. Sci. Philadelphia, Vol. , ¡912,p. 510, pl. 24, fig 3.
The valves are gently convex towards the. beaks; the right valve issomewhat more convex than the left. There äre about 24 pIic on the rightvalve which have very deep sloping sides, and are parted by interspaces wideithan theribs. Over all these, there is a fine concentric sculpture of delicate.lamellae which remains much more prominent in the interplical spaces. Theantörior ear is nonplicate.
Height, 58; width, 6o mm.
OCCURRENCE: Gatun formation, Panama Canal Zone.
HORIZON: Gattin formation.
PECTEN CIRCULARIS Sowerby
Plate 2, Figs. 9, ga.
Pecten circularis Sowerby. Proc. Zool. Soc. London, £835, p. zio.Arnold, U.S.G.S.Prof. Pap. 47, 1906. p. 125, pl. . Figs. 6 and 7.
Valves subequal about as long as high; very convex, inequilateral, theposterior part of the disk being somewhat obliquely produced; margins sharply
serrate. The right valve has 19 to 21 flat-topped piic, with sides steeplysloping; the interspaces are müch narrower than the plic, sculptured byobsolete, wavy lines of growth; hinge line about two-thirds the length of theshell; ears equal in length; anterior ear with four faint plic and numerousimbricating incremental lines; byssal notch deep, with more faint radiais onthe lower half. Left valve darker in color than the right, with sharp con-centric lamina on its disk. Cardial crura well developed. Color pattern fromlight to dark brownish red.
Pecten circ*4aris Sowerby, Proc. Geol. Soc. London, 1835, p, z
This shell is somewhat longer than high, subequivalved, biconvex, beingsomewhat obliquely produced posteriorly; margins more or less sharply ser-rate; sides being straight and sl9ping at a steep angle. There are i to 21prominent squarish, flat-topped pIic, ornamented with looped incrementallines near the periphery of the disk; interspaces very much narrower than theplic flat, ornamented by a dense fringe of fine, sharp, concentric lameIl;hinge line more than one half as long as the disk; anterior ear is somewhatlonger than the posterior, and ornamented by low ridges ajtd numerous im-bricating concentric lines; posterior ear nearly rectangularly truncated; byssainotch of medium size.
Shell of medium size, hiconvex, inequilateral. Right valve with low,flat-topped plic, have sides gently sloping; interspaces narrower than theplic, with fine, sharp, inibricating lamelle. Posterior ear slightly notched,anterior nearly rectangularly truncated. Hinge line longer than one half ofthe length. This species differs from the Recent P. circularis by its moreprominent concentric striations.
PECTEN cf. LATIAURITUS FIJCICOLUS DaliPlate 2, Fig, Ii
Peel en latiaursius var. fucicolus Dali. Trans. Wagner Free Inst. Sd., Vol. 3. Pt. 4.t8g8, p. 710,ArnOld, U.S.G.S. Prof. Paper 47, 1906, p. 13!, pl. 46. fig. 8.
Shell slightly longer than high, subequivalved, inequilateral, slightlyconvex; disk oblique, sides nearly straight; margins rough; 15 low, rounded,wide puce, sculptured, with obsolete concentric lamine on the disk; earsunequal, posterior one much longer than the anterior, nearly rectangularlytruncated, byssal notch deep, with five prominent radiais on both ears, with
56 Bulletin of the Geological Society of China
concentric larnel1, hinge line about two-thirds of the length; no sinus be.
tween the posterior ear and the disk; surface crossed by zigzag streaks o1white.
Height, 43; width, 45 mm.HORIZON: Recent.
PECTEN LAT1AURITITS Conrad SPLF.NDENS n. -var.Plate 2, Fig. u.
Peaen ¡ati,zuritus Rogers, The Shell Book p. 417
Shell slightly longer than high, subequivalved, slightly convex, inequi-lateral; disk oblique to the hinge line; sides nearly straight; margins rough.Left valve with 14 plic prominent, rounded; interspaces almost equal to theplic, sculptured by numerous fine concentric lamellz; hinge line longer thantwo-thirds the length of the disk; posterior ear longer than the anterior, theformer nearly rectangularly truncated, the latter deeply ndtched, eachsculptured by fine radiais witil numerous concentric lines. Shell brownish red.
This species differs from P. latiauritus Conrad var. fucicolus Dali in itsfine thread-like concentric striations.
Height, 22; length, 23 mm.HoRIzoN Recent.
PECTEN LATIAURITUS Conrad INDENTUS n. var,Plate 2, Fig. 13.
Shell slightly longer and high, subequivalved, slightly convex, inequila.teral, the disk being somewhat oblique to the hinge line; sides nearly straight;margins serrate. Right valve with 14 squarish plice and flat interspacesequal to the plic sculptured by fine, prominent concentric lameilme; hingeline longer than two-thirds the length of the disk; posterior ear longer than theanterior, the former nearly rectangularly truncated, the latter deeply notched,each sculptured by about five radiais with concentric imbricating lame1l.
This species differs from the above two varieties in its squarish plications.Height, i; length, 22 mai.HORIZON: Recent.
PECTEN (AMUSIUM) LUNA Brown and PilsbryPlate 2, Fig. 14.
Pecten ¡una Brown and Pilsbry, Proc. Nat. Sci, Philadelphia, Vol. 64, 1912, p. 514,pl, 33, fig. s.
Li: Miocene & Recent Mollusca of Panama Bay 257
Shell subcircular, siight1y convex, ears comparatively small, depressedbelow the plane of the valve and separated by a ledge; surface,smooth, with faint growth line and very fine radial stria. Internai surfacesculptured with paired plic and equal interspaces.
OCCURRENCE: Gatun formation, Isthmus of Panama
PECTEN (AMusIuM) sp.Plate 3, Fig. '15.
Shell rather small, rather flat, smooth with faint growth line; internallysculptured by paired ridges.
HoRIzoN: Gatun formation.
Family CRASSAtELLIDE DaliGenus CRASSATELLITIDJ Kruger
CRASSATIT.T,ITES RUDIS n. sp.Plate 3, Fig. ¿6.
Shell solid, attenuated anteriorly; umbos small, depressed; resiliferpresent; hingeplate heavy, flat, with two cardinal teeth in each valve; lateralteeth present, one posterior present; adductor impressions deep, palliai linesimple. Surface sculptured by numerous, cOncentric, nodulose lameil whichbecome prominent ridges near the umbo. This feature is very characteristic.
Ven,s orb icularis Linné, Syst. Nat., cd. ¡0, ¡758, P. 688.Codakia orbicularis Maury, Bull. Amer. Paleo., No. 29. ¡917, p. 202, pI. 35. Fig. z.
258 Bulletin of the Geological Society of China
Shell of medium size, rounded posteriorly and anteriorly; beaks small;surface rather scaly, sculptured by many radial plice, alternating with finerthreads especially on the posterior end, anterior with numerous, fine, con..centric lameliz.
Plate 3, Fig. 19.Myriaea ¡imo,liana Dali, Trans. Wagner Free Inst. Sei. Vol. 3, pt. 6, 1903, p.
1358, pl. 52,Fig, xo.-.--Olssou, Bull. Amer. Paleo., No. 39, 1922, p. 22!, pI. 32, Fig. II, 23.
Shell small, thin, and slightly convex, surface sculptured by fine, thinand sharp, elevated, concentric lamellae, slightly nodulose; beaks small andpointed; lunule more smooth than the rest of the surface.
OCCURRE.CE: Gatun Stage, Port Limon, Costa Rica.HORIZON: Gatun formation.
Phacoides hispanio1zna Maury, Bull. Amer. Paleo. No. 29, 1917, p. 204, pl. 35, fig. 4.
Shell thin, subcircular, slightly convex, beaks small, acute, directedforward. On the umbo, only concentric lines are shown; the center of the valveis sculptured by radial plicae and concentric lines, marked by minute spinosebeads on the intersecting places of the two sets of sculpture, the primaryradial plicae alternate with two or three fine secondary striae which disappeartowards the beaks. Hinge line normal with two strong lateral teeth andone cardinal tooth.
Height, ?; Length, g mm.OCCURRENCE: Gatum Stage, Port Limon, Costa Rica.HORIZON: Gatun formation.
Family CARDIID.IE FischerGenus CARDIUM Linné
CARDIUM cf. PROCERUM SowerbyPlate 3, Fig. 21.
Cardi iun prowurn Sowerby. Proc. Zool. Soc. London, 1883, p. 83,Martini andChemnitz, Sip. conchvlien-cabinet, Vol, X ¡888, p. 58, pl. lo, Fig. 12, l.
Li: Miocene & Receni Mollusca of Panama Bay 259
Shell very convex, nearly equilaterial, rounded oval. Slightly higherthan long. Unibos prominent, incurved, turned slightly forward. Surfacemarked by 24 radiating squarish plic with fine concentric lamellae. Tocardinal teeth, one anterior and one posterior in each valve. No lunule orescutcheon present. Ligament external. Adductor impressions very shallow.
Height, 47; length, 43 mm.HORIZON: Recent.
CARDUM PARVULUM n. sp.PLate 3. Fig. 22.
Shell less convex than that preceding, nearly equilateral, slightly longerthan high. limbos incurved, turned slightly forward. Surface marked by24 radiating p1ic, somewhat sharp, interspaces narrower than the plic,with fine concentric lamell.
This specimen is characterized by its small size, and differs from C./'rocerum Sow. in its oblong form, but it might be a young shell.
An internal mold, howing the internal sculpture of the genus.HORIZON: Gatun formation.
Family VENERIDI LeachGenus CLEMENTIA Gray
CLEMENTIA DARIEN'A (Conrad)Plate 4, Fig. 24,
Me,elrjx dariena Conrad, Pacific R. R. Report, V p. 328, pl. 6, Fig. 55.Clementia dariena Brown and Pilsbry, Proc. Acad. Nat. Sci. Philadelphia, Vol. ,
19f I, . 37!, Çd. 6, fIg. 55.
Shell thin, large, oblique, inequilateral; beaks prominent; surfacesculptured by concentric ridges which become low, imbricating lamell onthe umba, some of the ridges sometimes discontinuous.
Height, 56; length, 58 and diam., 13 mm.OCCURRENCE: Gatun formation, Costa Rica and Santo Domingo.HORIZON: Gatun formation,
Genus VENUS TAnne
VENUS EBERGEN VII BösePlate 4, Fig, 23,
260 ßulezin of the Geological Society of China
Venus ebergenyii Böse, Bol. Inst. Geol. Mex., No. 22, 1906, p. 28, pl. 2. figs. 4-17.
Shell subtriangular, inequilateral, anteriorly round, posteriorly angular,ornamented with high concentric ridges which die out gradually into lowlamellm towards the umbo, on the ridges obscurely striated vertically, betweenthe rigdes covered, by many lameil; umbo rather small; lunule depressed,minutely striated; posterior area prominent, striated.
Shell subtrigonal, inequilateral, anteriorly rounded, posteriorly angular,sculptured by numerous small, close radiating policul, interrupied by highconcentric crenulate ridges which are higher and closer towards the ventralmargin; umbo rather smaLl; lunule impressed, minutely straited, circumscribed
by a sharp groove; post.rior cardinal area prominent, striated
On the disk the p1icu1 are distinctly pafred but on the umbo, theconcentric ridges die out gradually into lameliz. and the plicul are evenlyinterspaced.
Topes staminetz Rogers. The Shell Book. 2908, p. 335.
Shell rounded posteriorly and anteriorly; beaks 3mall but prominent;surface sculptured by o uneven radial plic, beautifully beaded at someportions; with numerous concentric impressed lines on the ribs, interspacesnarrow, with the concentric, imbricating IamelI. Lunule slightly nodulose.
Height, i; length, 19 mm.HORIZON: Recent.
Li: Miocene & Recent Mollusca of Panama Bay 261
Genus PrrARIA Roemer
PITAIu& (LAMELLICONca&) ACUTICOSTATA Gabb
Plate 4, Fig. z8.
Filaria acalicoslmla Gabb. Trans. Amer. Pail. Soc., Vol. i, 1873. p. 25o.MaUty,Ball. Amer. Paleo., No. 29, 1917. p. 216. pL 37. fig. 2.
Shell of medium size, oval triangular; anterior rounded, sculptured bymany concentric ridges and with faint radial striae.
Height, 31; width, 41 mm.
OCCURRENCE Zone G, Lower Miocene, Santo Domingo.
HORIZON: Gatun formation.
PITARIA (LAMELLICONCHA) LABRANA Maury
Plate , Fig. a.
Pitaria iibUaia Máury, Jour. Ac, Nat. Sol. Pnila. (2) t. 1912, p. 57, pl. g,figs. 14. 15.
Shell small, elongate, oval, anterior rounded, rather compressed,sculptured by many concentric round.edged lamellae which die out graduallytowards the beaks; beaks small.
Height, zi; length, 21 mm,
ø(CURRENCE: Brighton, Trinidad.
HORIZON: Gatun formation.
Family TELL1NID Desbayes
Genus TELLINA Linn.
TELLINA CIBAOICA Maufy
Plate 4,Fig. 30,
Tellern cil,rnoica Maury. Bull. Amer. Paleo., Vol. , No. 29, 1917, p. 223, pl. 39.fig. lo.
Shell medium in size, very highly 1ished; shallowly sulcate posteriorly;right valve has two lateral teeth. Surface sculptured by very fine, impressedlines obsolete posteriorly, and marked by exceedingly fine close radial striae.
Height, z; length, 45 mm.
OCCURRENCE: Lower Miocene, Rio Cana at Caimito Santo Domingo.
HORIZON: Gatun formation.
262 Bulletin of the Gelogical Society of China
TELLINA COSTARICANA OlssonPlate 4, Fig. 3Z.
Teltina coslaricana Olsson, Bull. Amer. Paleo., No. 39, 1922, p. 251, pl. 26, figs. 6,
Shell rath"r small, depressed; beaks small and inconspicuous about themiddle of the shell so that the anterior and posterior ends are of nearly thesame length; posterior wide and rounded; the anterior narrower and lessrounded at its extremity; sides nearly straight, surface sculptured by eveaconcentric lines which are slightly lameilose on the posterio-dorsal margin.
Height, 22; length, 38 mm.OCCURRENCE: Gatun Stage, Banana River, Costa Rica.HoRIzON: Gatun formation.
TELLINA PANAMANENSIS n. sp.Plate 5, Fig. 32.
Shell medium in size, inequilateral, beaks small, posterior end roundedand wide, the anterior less wide and round, surface sculptured by concentric,imbricating lamell which are very prominent, and marked by numerous closeradial lines which only can be seen under a lens.
This species is related to T. costaricana Olsson, but differs f rom it by itsprominent concentric, imbricating lamell.
Shell medium in size, possibly nearly equilateral, beaks depressed, small,posterior wide and rounded; surface sculptured by slightly wavy concentricimpressed lines, with very fine close radial lines.
This species is characterized by its nearly equilateral form and especiallyits slightly wavy concentric impressed lines.
Height, 30 mm.; length?
HORIZON: Probably Gatun formation.
Family PSAMMOBIID Dali
Genus PASAMMOI3IA Lamaick
PsAMloBIA sp.Plate 5, Fig. 34.
Shell inequilateral, posterior wide and rounded, anterior less wide but
Li: .11iocene & Recent Moflusca of Panama By 263
still roanded; beaks small but prominent, hinge line rather long; surfacesculptured by numerous fine lamell with fine, close, radial strie.
This specimen is related to Recent P. mexima, but it is medium in sizeand not as fresh as recent shells.
Shell rather large, anterior rounded, beaks small; surface sculptured byconcentric ridges, more than 40 Ifl number, some of the ridges discontinued
and marked by broader, concentric ridges internally, resilifer present.This shell is closely related to R. canalicilala Say but differs in its
ridge-bounded escutcheon, and larger shell.Height, 86; length, 74 mmHORIZON: Recent.
Family CORBULIDiE Fleming
Genus CORBULA Lamarck
CORBULA cf. COLLAZICA Mamy
Plate 5, Figs. 36, 36a.
Corbuia collazica Maury, N. Y. Acad. Sci. Vol. III, pt. i, 1920, p. 44, Pl. 6,figs. ¡o, ix.
Shell oval triangular, rather small, anterior end rounded and theposterior produced, truncated obliquely, surface sculpturcd with many fineclose set, even, cqncentric ridges, alternating with linear interspaces.
Shell inequitateral, very convex; beaks small but prominent; very shortscaly at the middle part; surface sculptured by numerous concentric lamelke.
This species is related to C. chittyana Adams but differs in its prominentumbo.
264 Bulletin of the Geological Society of China
Height. 24 mm.; length?HORIZON: Gatun formation.
CORBULA GLYPTA n. sp.
Plate . Fig. 38, 38a,
Shell rather small, thin, oval triangular, inequilateral.. posteriorrounded,and anterior angular, truncated obliquely; beaks small; depressed transverselycross the valve. Surface sculptured by numerous fine lamelbe; lunuleimpressed.
This species is related to C. kjoeriana Adams, but differs in its depressedshell.
Height, 13; length, 24 mm.
HORIZON: Probably Gatun formation.
Com3urA cl. SWIFIANA Adams
Plate . Fig. 39,
Co,'buio swiftia,ga Adanu, BuU. of U.S. Nat. Mus. No. 37, 1889. pl. 2, fig. 5.
Shell inequilateral, convex, posterior somewhat angular, anteriorrounded; beaks small; surface sculptured by numerous fine concentric lamelI8e,slight lamelle posteriorly.
Height, 25; length, 31 r.in.
HORIZON: Gatun formation.
Class GASTROPODA Snails
Subclass STR.EPTONEURA Spengel
Order ASPIDOBRANCHIA Schweigger
Family PATELLID4 Carpenter
Genus PATELLA Lin né
PATELLA CALIX n. sp.
Plate 5, Fig. 40.
Shell cup-shaped, oval, depressed conical, with subcentral apex. Surfacesculptured by the primary alternating with several secondary radial p1ic)and with concentric ridges. The concentric sculpture on intersecting theradial, raises into beads.
Li: Miocene & Receni Mollusca of Panama Bay 26S
HORIZON: Probably Gatun formation
PATELLA CALICULUS n. sp.
PLate 6. Fig. 41.
Shell small, cup.shaped, oval, depressed conical, with sub-central apex.Surface sculptured by the primary plic alternating with several secondaryradial plic, and with concentric ridges. The concentric sculpture on inter-secting the radial, raises a row of beads surrounding the apex. Apex de-pressed.
This species is characterized by its sculpture and a few plic.
HORIZON: Probably Recent.
Family SQLARIIDJ Chenu
Genus SOLARIUM Lamarck
SOLARIUM GATUNENSE Toula
Plate 6, Fig. 42.
Solariun. gatuwsnsa Toula, Jahr. der Geai. Reich. s9o9, p. 692, pl. 25. (i). fig. 3.
Shell depressed conical, narrowly and deeply umbilicate; whorls angular,aperture somewhat equilateral. Surface sculptured by spirals with beadedand granulated character, and becoming obsolete on. the later whorls so thespirals become stnooth except for growth-lines.
Height, 26; width, 36 mm.
OCCURRENCE: Gatun formation Panama Canal; Costa Rica.
HORIZON: Gatun formation.
Family CAPULIDA Cuvier
Genus CREPIDULA Lamarck
CREPIDULA PLANA Say
Plate 6, Fig. 43, 44.
Crepidula plana Say. U. S. Nat. Mus.. Bull. , 1889, Pl. 50.
Shell flat, elongate, apex marginal; platform covering about hail thelength of the shell. The Gatun specimensare small.
HORIZON: Two shells belong to Gatun formation (fig. 43) and ontRecent (fig. 44).
Bulletin of the Geological Society of China
CREPIDULA cf. PLANA Say
Plate 6, Fig. 45.
Shell elongate, apex marginal, not enrolled; platform covering about halfthe length of the shell. The shell is very much distorted instead of flat;otherwise it fits this species perfectly.
HORIZON: Probably Recent.
Family NATICIDIE Forbes
Genus NATICA Scopali
NATIC.k GUPPYANA Tonta
Plate 6, Fig. 46.
Watca (Sttg'maulaz) .guppyaua Tonta, Jahrb. der K-K. GeoI. Reichsanstalt. Wien.,
tog. Vol. 8, p. 696, pl. 25, fig. 6.Otsson, Bull. Amer. Paleo.. No. 39, £922, p. 156, pl, 13.
figs, 13, 14, 15.
Shell with short spire and large body whorl; aperture large, semicircular,
expanded, broad roun.d anteriorly. Surface sculptured by even, wide anddeep sulcations, which cross the face of the whorl from its upper suture to the
umbilicus.Height. 21 width, i6 mm.OCCURRENCE: Gatun, Banana River, Costa Rica.
HORIZON: Gatun formation.
N ATCA YOU NGI Mury
P1ate 6. Fig. 47. 475
Na(ics youngi Maury, BuU. Amer Paleo, No. 29, 1917, p. 135, pl. 23, figs. Il, £2.
Shell subglohular, with short spire and large body whorl; aperturesubcircular; whorls 5, rounded; surface smooth except for growth lines; pos-terior callus of inner Lip thickest at the angle of the aperture; umbilical calluscoiled on the umbilicus wall near the base, leaving the upper part of the
umbilicus open.
Height and width, 24 x 18, 40 x 30 mm.OCCURRENCE: Lower Miocene, Caimito, Santo Domingo, Costa Rica and
Chiapas.
HORIZON: Gatun formation.
Li: Miocene & Recent )lfollusca of Panama Bay 2f27
Genus POLINICES Montfort
POLINICES STANISLAS-MEUNIERI Maury
Plate 6. Fig. 48.
Polinices stanislas-,neunieri Maury, Bull. Amer. Paleo., No. 29, 1917, p. 136, pl. 23,figs. ¿5. i6.
ShIl oval, with short and conical spire and large body whorl which maketogether five and a half rounded whorls; body whorl very slightly concave infront of the suture, others evenly rounded; aperture simicircular; inner lipwith a thick posterior callus extending half of the distance from the angle ofthe aperture to the base, and concealing the upper part of the perforation; thecallus is then reduced to half its width by a rectnagular truncation.
Tun'itella gafunensis Conrad, Pacific R. R. Rep., VI, pl. , fig. 20.Brown andPilsbry, Proc. Acad, Nat. Sei. Phila., Vol. 63, 1926, p. 358, pl. 27, fig. .
Shell turreted, surface sculptured by spiral threads, crossed by bendingtransverse lines, the upper, surface of each whorl very much excavated.Aperture subcircular. The base smooth.
Height,?; width, to mm.OCCURRENCE Ballast Point, Isthmus of Panama.HORIZON: Gatun formation.
Family CERIT}I1IDA Menke
Genus POLAMIDES Brogt.
POTAMIDES META n. sp.
Plate 6, Fig. 50,
Shell turreted, with epidermis, aperture with faint canai; surfacesculptured by spiral lines and crossed by longitudinal threads, at the intersect-
a68 Bullets', of the Geological Society of China
ing places of the two sets of sculpture, marked by beads; and marked by wideseparated, strong, ridges.
This species is related to P. sacrata Gid., but differs from it in its lessacute spire and its thicked outer lip.
Height, a; length, 9 mm.HORIZON: Probably Recent.
Family COLUMBELLIft TronchelGenus SnofBINA MÔICli
STROMBINA LAEVISTRIATA n. sp
Plate6, Fig. 52.
Shell f',siform, solid, with slender, conical spire, a little attenulatedabove, elsewhere smooth in outlines; whorls eight. nearly flat; surfacesculptured by fine, close, spiral, and longitudinal ribs, with an impreasedspiral groove just below the suture. On the body whorl there are longitudinalwrinkles, deuticutated within. Aperture narrow and rather short; vaux pro-minent. Anteriorly there are spiral grooves.
This species is related to S. cyphonotus Pilsbry and Johnson, but diffeisin size and ornamentation.
Shell fusiform, with slender, conical spire; surface smooth, with longi-tudinal wrinkle on the surface of the outer lip, a'sinall, strong varix present.At the base there are spiral grooves. Surface ornamented by beautiful, pur-ple, wavy streaks.
This species is characterized by its slender form and its purple, wavystreaks.
Homzos: ecent.Family NYCTILOCHID Dali
Genus TRITON Montf.
TRrroN cf. BARTHELEMYI BERNARDI
Plate 7. Figs. 53. 53a.
Trifow barthekmyi B&nardi, Journ. Conch., VI, p. .Maxtini and Chemnitz,Sys. Conch. Cabinet, ¡888, p. 222. pJ. 62, fIg. I.
Li: Miocene & Recent Mollusca of Panama Bay 269
Shell fusiform, spire moderate, high shoulder angle rather sharp; innerlip thicked internally and notched, ccuterlip expanded; whorl 7; protoconchsmooth. Surface sculptured by .5-7 uneven, spiral bands with many lower,longitudinal riblets.
Height, 74; width, mm.HORIZON: Recent.
Genus DISTORTRIx Link.
DISTORTRJX GATUNENSIS Tonla
Plate Fig. 34.
Distortri.x gahus.nsis Toula. Jahrbuch der Geol. Reich., ¡909, p. 700. pl. (i) fig. ¡o.Shell fusiform, spire moderately high, aperture with thickened outer lip
and open, slightly bent canal. Operculum horny with marginal nucleus,varix present. Surface sculptured by spirals and longitudinal ribs, withbeads at the intersecting places of the two sets of sculpture. At the base.there are spiral grooves.
Plate 7, Fig. 56.Metula caitcellata Gabb, Trans. Amer. Phil. Soc., Vol. i, 1873, p. 205.Brown and
Pilsbry, Proc. Ac. Nat. Sci. Philadelphia. Vol. 63, ¡91!, p. 3,51.
Shell elongate-oval, with epidermis; spire m*derately high, aperture
270 Bulletin of the Geological Society of China
rather narrow, with short notch. Surface sculptured by many wider,spirals and longitudinal riblets, but less in number than .11leula gabbi Brownand Pilsbry. The second and the third whorls separated by a deep groove;the protoconch is lost. The spirals pass the longitudinal folds. Under a
microscope the secondary longitudinal riblets can be seen.
Height, 38; width, 12 mm.
OCCURRENCE: Lower !Aiocene, Santo Domingo, Panama Canal Zone, andCosta Rica.
HoRIZoN: Gatun formation.
Genus MELONGENA Schum
MELONGENA (PUGILINA) MENGEANA flail
Plate 7. Fig 57.Solesosleira meugaana Dali, Wagner Free Inst. Sd., Vol. 3, p, 122, pI 9, Fig. i.
Melongena meng.a.a Biise. Bol. Ins. Geol. Mex., 1906. p. 40. pl. IV, Fig. z,
Shell fusiform, small, bulbous nucleus lost, only six sculptured whor1
remained, the last whorl enlatged very much, with transverse folds on the
surface, 12 on the last whorl, beginning near the suture and continuing over
the periphery, becoming obsolete on the base of the whorl; the incremental
lines are also somewhat alternated in strength and quite distinct; the spiralridges, sharp, even, crossed the folds and descend into the interspaces, again
with two spiral threads on each side of the ridges, the ridges being weeker on
the canal. Aperture elongated; the throat strongly lirate.Height, 29 diain., i8 mm.
Geological range: This species was oniy described from the Pliocenc
beds of Florida and other localities.
HoRIzoN: Gatun formation.
Family VOLULIDA Gray
Genus MARGINELLA Lamarck
MARGINELLA EVAX n, sp.
Plate 7, Fig, 58,
Shell small, oblong, widest at the upper third of the length. Spire
conical, short, and so enveloped that the suture is blended. The outer lip is
broad, straight, thickest outside, incurved and not denticulated, and dilated
near the lower end. Columella bears four folds.
Li: Miocene Recent Mollusca of Panama Bay 271
This species is related to M. gatunensis Brown and Pilsbry, and M.leande, Brown and Pilsbry, and differs from both in its proportion ofdimensions and from the former by its lack of dentation on the inner side ofthe outer lip.
Height. 27; diam., ¡3 mm.
HORIZON: Probably Gatun formation.
MARGINELLA cf CINERACEA QUADRIPLICATA Böse
Plate , Fig. .59.
Margineila cine.-acea quadripicala Böse, Bol. Inst. Geol. Mex., No 22, ¡906, p42, pl. 5, hg. z
Shell small, oblong, spire conical, short, and so enveloped that thesutures blend. The outer lip thin, without any thickened lmrt; the inner lipbears four folds. Aperture open, somewhat straight, abruptly but slightlydilated at the lower end.
Height, 2o; width, 8 mm.
HORIZON: Probably Gattin formation.
Family OLIVID d'Orbigny
Genus OLIVA Martyn
OLIVA cf. LITTERATA Laznarck
Plate ', Fig. 6o.Ojiva Ullerata Lamarck, Ann. du Mus. XVI, p. 3!5.Martjnj and Chemnitz, Sys.
Concho Cabinet, V, ¡888, p. 64, pI. z, Fig. i-8.
Shell rather small, elongate, beautifully ornamented by zigzag brownstreaks, widest at the upper half of the length. Spire conical, short; with anarrow canalicute suture. The outer lip broad. The inner has sixteen im-plications. Aperture narrow and long, with an outwardly reflected callusanteriorly. Canal short.
Height, 26; width, 7 mm.HORIZON: Recent.
OLIVA CALLOSA n. sp.
Plate 7, Fig. 6z.
Shell solid; spire very low, with a narrow canaliculate suture; surfaceornamented by zigzag reddish-brown streaks nd with growth lines. The
272 Bulletin of the Geological Society of China
outer lip broad, the inner has about i6 implications. Aperture open and long,with an outwardly reflected callus anteriorly. Canal short.
This species differs from O. mariae Durros in its low spire.
Height, 28; width, 19 mm.
HORIZON: Recent.
Family CANCELLARIIDA Adams
Genus CANCELLA1IA Larnarck
CANCELLARIA HARRISI Maury
Plate 7, Fig. 62.
Canc4laria htzrvisi Maury. Bull. Amer. Paleo.. No. 29. 1917. p. 64, pl. jo, fige. 9, 10.
Shell fusiform, 8 whorls, the first two smooth, on the third ribs andspirals appear; the latter increase from stria to flat narrow bands, on the lastone alternating with finer secondary and tertiary spirals; on crossing theribs, at the shoulder are nodulose, on the body whorl ribs 14, on the earlier
whorls the ribs are more numerous. Columella triplicate, the lower fold
bordering the anterior canal. Aperture open; sharp keel on the base.
Shell small, very slender, elongate. Each whorl sculptured by asubsutural band about a quarter the length of the whorl, a deep sulcusbeneath the subsutural fasciole, beneath which there are G to 7 spiral, lowbands crossed by higher, longitudinal wider-separated riblets.
Shell turreted, slender, with an acute soire. Each whorl scuintured bya subsutural band about a quarter the. width of th whorl, marked off by afurrow, and beneath which five or six spiral cord; and with many fine,longitudinal growth-lines which bend a little at the furrow. Columehla twisted,with sharp keel at the back.
Height, 44; width, g mm.
OCCURRENCE: Lower Miocene, Cercado de Mao, Santo Domingo.
HORIZON: Gatun formation.
rEREBRA MACROSPIRA n. sp.
Plate 8, Fig. 66.
Shell long, slender; Whorl 17 (this specimen is a decollated one); surfacesculptured by arcuate, longitudinal riblets, very low at flic last six whorls,and passing into sharp defined arcuate riblets upard. Cohlumella not plicated,but a sharp keel at the base.
This species differs from T. sulcifera Sowerby in. its ornamentation.Height, r; diam., r8 mm.
HORIZON: Gatun formation.
274 Bulletin of ¿he Geological Society of China
TEREBRA CRACILENTA n. sp.
Plate 8, Fig. 67.
Shell slender, with acute spire, ornamented by subsutural band about aquarter of the width of the whorl marked off by a furrow, beneath which fourstronger spirals and two weaker spirals which intersecting with radial longi-tudinal riblets, rises into very prominent beads on the subsutural band andthe four upper spirals, and especially prominent on the fourth spiral.
This species is related to T. goluneusis Maury, but differs in ornamenta-tion.
Height, 45 diam., io mm.HoRizoN: Gatun formation.
TEREBRA TENUIS n. sp.
Plate 8, Fig. 68.
Shell slender, with acute spire, ornamented by a su bsutural band abouta quarter of'the width of the whorl, marked off .by a furrow, beneath whichare four spiral bands, which intersecting with radial longitudinal riblets, risesinto prominent beades; below the four bands are one to two faint bands.
This species differs from T.. gausapata laefasciola Maury in itsornamentation and more radial riblets.
Shell small, solid, whorls from eight to nine; surface sculptured bymoderate strong ribs which on the spiral whorls pass from suture to suture butare only slightly flexed near the upper suture; on the body whorl, ribs I',which are much enlarged and outer lip thickened; the ribs do not reach thecanal; and marked by a few spiral threads, and covered by fine, irregularthreads which are nearly obsolete on the upper porlions of the whorls but
Li: Miocene & Recent Mollusca of Panama Bay 27
are strong on the base and the canal; aperture subelliptical with a short,bended canal, denticulated wltnin the outer lip.
Height, 31; width, lo mm.
OCCURRENCE: Gatun Stage, Port Limon, Costa Rica.HORIZON: Gatun formation.
DRILLIA ZOOKI Brown and PilsbryPlate 8, Fig. 70.
Drill ja took î Brown and Pilsbry, Proc. Ac. Nat. Sci. Philadelphia, VoL. 63, 1911, p.345, ¡il. 23, Fig. 8.
Shell small, with long and arcuate spire, àperture narrow and short.Surface sculptured by prominent longitudinal folds, xx on the last whorl,below the fasciole below the suture; on the folds crossed by spiral lines. Onthe body whorl, the folds gradually die out, only spiral lines ornamented withcanal at the base.
Height, z; greatest diam.. 7 mm.
OCCURRENCE: Gatun formation, Isthmus of Panama.HORIZON: Gatun formation.
DRILLIA INAEQUISTRIATA n. sp.Plate 8, Fig. 71.
Shell slender and long, the last whorl occupying over half the height ofthe shell, aperture narrow and rather long, with canal at the base. Beneaththe fasciole below the suture, surface ornamented by prominent folds, ratherirregular, and crossed by spirals.
This species is characterized by its slender form and close folds.Height, 55; width, 9 mm.HORIZON: Probably Recent.
Family CONID1 AdamsGenus CONUS Linné
CONUS IMITATOR Brown and Pilsbry
Plate 8, Figs. 72, 72a.Conus imijatoy Brown and Pilsbry, Bull. Amer. Paleo., No. 3g, 1922, p. 45, pl.
3, Fig. 39.
Shell conical, moderate high spire, rather flat; aperture narrow and long;shoulder angle rather sharp, whorls slightly concave between the sutures; sur-face sculptured by 3 or more faint raised spirals ard strongly arcuate
276 Bulletin of the Geological Society of China
growth-lines; the last whorl with faint spirals above and with about i spiralgrooves at the base.
Height, 17; width, ir mm.OCCURRENCE: Gatun Stage, Costa Rica.
HoluzoN: Gatun formation.
Brown, A. P.,
Chenu, J. C.,
Clark, Shattuck and
Cooke and Vaughan,
Li: Miocene & Recent Mollusca of Panama Bay 277
Cossman, M.,
Dali, W. H.,
BIBLIOGRAPHY
Adams, C. B. Catalog of Shells collected at Panama. N. Y. Lyceum ofNatural History, May lo, 1852.
Arnold, R., Tertiary and Quaternary Pectens of California, U. S. G. SProfessional Paper, No. 47, 1906.
Augilera, j. G., Fauna Fossil de la Sierra de Catorce. Institute GeologicodeMexico. Bol. 1,1895.
Bartsch, P., Report of the Turton Collections of South Africa MarineMollusks. Bull, of Smithsonian Institution, U.S. NationalMuseum, 91, 1915.
Binney, A., The Terrestrial Air Breathing Mollusks, Vol. i-d, CharlesC. Little & James Brown, Boston, 185o.
Binney, W. G.,. The Terrestrial Mollusks of North America. Welch.Bigetow & Co., Cambridge, 1878.
Böse, P. E.. Fauna Teroiarias de Mexico, Inst. Geol. de Mexico. Bol.22, 1906.
Geologia de Chiapas Y Tabasco, Inst. Geol. de Mexico,Bol. 20, 1905.
Bosworth, T. C., Geology and Palaeontology of Northwest Peru. MacMillan& Co.. 1922.
Brown, A. P. and Pilsbry, H. A., Fauna of the Catun formation. Proc.Acad. Nat. Sci. Philadelphia, Vol.
73, 1921.Fauna of the Gatun Formation, Isthmus of Panama.Proc. Acad. Nat. Sci. Philadelphia, Vol. 64, 1912.Manuel de Conchyliologie et d'Paieontologie Conchylio-logique. Librairie Victor Masson, Paris, 1859.Dali, Wm. H.,1904.Contribution tothe West Indies.
Miocene, Maryland Geol. Survey,
the Geology and Paleontology ofCarnegie Institute of Washington,
Publication 291, 19X9.
Etude Comparative de Fossiles Mioceniques Recueilus ala Nartinique et a l'isthme de Panama, jour. deConchyliogie, Vol. 71, 1913.
New Species of fossil shells from Panama and CostaRica. Smithsonian Miscellaneous Collection, Vol. 59,No. 2.
278 Bulkin of the Geological Sociely of China
of the
Bull. Am. Pal. Vol. 5, No. 27.
A Preliminary Catologue of the Shell-hearing MarineMollusks and Brachiopods of South Eastern Coast ofU. S., Bull. U. S. Nat. Mus. 37, 1889.
Diliwyn. L. W., Descriptive catalogue of Recent Shell, London. 1817.
Engerrand, J. Y. and Urbina, F., Prinaera Nota Aceroa de la FaunaMiocenica de Zuluzum (Chiapas). Bol. de la SociedadGeol. Mex. Tomo VI, 1909.
Gabb, W. M., On the Topography and Geology of Santo Domingo.Transactions of American Phil. Soc., Vol. 5, 1873.
Guppy, R. J. L., On the Tertiary Mollusca of Fanmica. Journ. o the
Geol. Soc. of London, Vol. 22, i866.On the Miocene Fossils of Haiti. Quart. Jour.Geol. Soc. of London, Vol. 32, 1876.
Heniken, J. S., Tertiary Beds in the Islands of Santo Domingo. Quart.Jour. Geol. Society, London, Vol. 6, i85o.
Hubbard, Bela Tertiary Mollusca from the Lares District, Porto RicoN. Y. Acad. of Sci. Vol. 3, Part 2, 1920.
Martini and Chemnitz, Systematisches Cónchilien.Cabinet Nurnburg, Vol.
3-II, 1857.1888.Maury. C. J., Santo Domingo Type Section and Fossils. Bull. Amer.
Paleontology, Vol. 5, No. 29 and o, 1917.New Oligocene Shells from Florida, Bull. Am. Pal. Vol.
4, No. 21, 1910.
Contribution of the Paleontology of Trinidad. Journ.
Acad. Nat. Sd. Phila,, Vol. 15, 19X3.Tertiary Mollusca from Porto Rico. N. Y. Acad. of Sci.,Vol. 3, Part I, 1920.
Olsson, A. A., The Miocene of Northern Costa Rico. Bull. Am. Pal.Vol. 9, No. 39, 1923.New Miocene Fossils.1916.
Pilsbry, H. A.., Revision of W. M. Gabb's Tertiary Mollusca of SantoDomingo, Proc. Acad. Nat. Sci. Philadelphia, Vol. 3,
1921.
Roemer, E., Monographie der Molluskengattung Venus Linne. Casse!,Verlag von Theodor Fischer, 1869.
Li: Miocene & Recent Moilusca of Panama Bay 279
Rogers, J. E., The Shell Book. Doubleday, Page & Co., N. Y. ¡goS.Sopper. C., Gebirgsbau und Boden des nordlichen Mittelamerika,
Ergenzungshaft ¡27, Zu Petermann's Mitteilungen,¡899.
Sowerby, G. B., Conchological Manual, Henry G. Bohn, London, 1852.Toula, F., I'auna von Gatun Am. Panama-Kanal. Wien, Geol.
Reichanstalt Jahrbuch, Vol. 58, ¡909.Tryon. G. W., PUsbry Ii. A. and Cooke, C. M., Manual of Concliology.
A series of volumes published by the author and Acad.Nat. Sci. Philadelphia, ¡st series, Vol. i-z', 2nd series,Vol. I-25, 1880.1920.
Structural and systematic conchology, Vol. ¡.3. Pub.lished by the author, ¡882.
Vaughan, J. W., and others. Contributions to the Geology and Paleonto-logy of the Canal Zone, Panama, aild Geologicallyrelated areas in Central America and West Indics. Bull.U. S. Nat. Mus. 103, ¡919
White, C. A., A Review of the Fossil Ostreidae of North America.Fourth Annual Report of U. S. G. S. ¡882-83.
Whitfield. R. P., Mollusca and Crustacea of the Miocene formations ofNew Jersey. U. S. G. S. Monography, 1894.
Wood, W., General Conchology, John Booth, London. ¡835,
k_0 R O'? AL
At 0A
ANCO
PANAMA
0Ff,Naosi
Contourinteraj Ioofeet
o Z 3 4Milei
,°anam a BayFrom np issued ¿y the/e(h'niaP canal Commission
C. L / Altj,1ffZ4
Explanation of
Plate I
281
Plate I
Figure Page
L Arca cf. pennelli Gabb x ., Gatun formation 252
z. Arca cf. /,itticeri Dali x r, Gatun formation 252
3,3a. Arca dariensis Brown and Pilsbry x 1.1, Gatun formation 252
Arca (Sczfrharca) golfoyaquensis Maury x I.z, Gatunformation 253
Ostrea sp. .9 Gatun formation 253
O.ctrea Sp. x .9 Recent 253
7,7a. Pecten reliquus Brown and Pilsbry x 1.25, (atunformation 254
8. Pecten cf. circularis Sowerby X .95, probably Gatuntormation 255
282
Li: Miocene & Recent Mollusca of Panama Bay Pi. I
Explanation of
Plate II
283
Plate II
Figure Page9. Peclen circulajris Sowerby X .g. Recent 254
ga. Peclen cf. circularis Sowerby x .r, Probably Gatunformation 254
lo. Pecten fililextus n. sp. x i, Gatun formation 255
ri. Pecten iatiauritus var. fucicolus Dali x r, Recent . . 255
Pecten latiaurilus Conrad splendens fl. Sp. X 1.2, Recent 256
Pecten laliaurilus Conrad indenius n. var. x. 9, Recent 256Peclen. luna Brown and Pilsbry X .9, Gatun formation 256
284
Li: Miocene & Recent Mollusca of Panama Bay Pl. II
Explanation of
Plate III
28
Plate Ill
Figure Page15. Pecten Sp. x .8, Gatu nformatiGtl . 257
i6. Crassatiflites ?udis n. sp. x .8, Gaturi 257
17. Lucina cf. callozoensis Hubbard x .ij, Gatmi 257
i8. Codakia orbicularis Linne X .95, Gatun, 257
Myrtaea litnoniana Dali X .95, Gatun formation . . 25
Phacoids hispaniolana Maury x .8, Gatun formation 258
Cardiutn cf. procerum Sowerby x .8, Recent 258
Cardium parovalun.z n. sp. x .8, probably Recent . 259
Cardium sp. x .9, Gatun formation 259
286
Li: if iocene & Recent Mollusca of Panama Bay Pl. III
Explanation of
Plate IV
287
Plate IV
Figure Page
Clementia dariena Conrad x i, Gatun 259
Venus ebergenyii Böse X .95, Gatun 259
Venus waüi Guppy x .8, Gatun formation 260
z6a. Same species x .8, Gatun formation 260
Tapes staminea Conrad x .9, Recent . . 260
Pitarla acuticostata Gabb X .95, Gatun 265
Pitaría labreana Maury X .9, Gatun 265
Telling cibaoica Maury x .9, Gatun 26t
35. Telina costaricana Ølsson x ., Gatun 262
288
Li: Miocene & Receni Mollusca of Panama flay Pl. iV
Explanation of
Plate V
289
Plate V
Figure PageTf1in« fa4arnanensis n. sp. x .q, Gatun 262
Telling tenuilineatus n sp x .8, probably Gatun forma-tion 262
Psammobia sp. x .85, probably Gatun formation 262
Raeta maxnna n. sp. X .9, Recent 263
36, 36a. Corbuía cf. coliazia Maury X .9, Gatun 263
37. Corbula al!iroslris n. sp. X .i, Gatun 263
38, 38a Corbula gly/)la n. sp. X .75, Recent 264
30. Corhula cf. swiftiana Adams x ., Gatun 264
40. Patella calix n. sp. x .9, probably Gatun - . 264
24)0
38a'
Li: Miocene & Recent Mollusca of Panama Bay Pl. V
Explanation of
Plate VI
291
Plate VI
Pf gu re PagePai sUa calcilus n. sp. x .9, Recent - 265
Sohirium gatussense Ioula X .9, Gatun . , z6
Crepidsila plana Say x .3, Gattin formation 265
Crepidula /'lana Say x .3, Recent 265
Crepidula cf. plana Say x .9, probably Recent 266
Natica guppyasa Ioula X .9, Gatun formation , 266Natica youngi Maury X .9, Gatun formation z66
47a, Same species x ., Gattin formation 266
Polinices slanislas-meunie,i Maury, x .8, Gattin formation 267
Tssrritella gatunensis Conrad z .8, Gatun 267o. Potamides mcta n, sp. x .8, probably Recent 267
51. Strombina Icevisiriata n. sp. x .8, Recent 268
Sirombina slegans n. sp. z .8, Recent - 268
292
Li: Miocene & Recent Mollusca QJ Panama Bay Pl. VI
Explanation of
Plate VII
293
Plate VIL
Figure Page
Triton cf. barthelemyi Bernardi x .8, Recent. 2(8
53a. Same species x ., Recent. z68
Distortrix gatunensis Tonla x .85, Gatun 269
Phös coslatus Gabb X .9, Gatun formation. 269
Metula cancellata Gabb x .85, Gatun formation 269
Melongena mengeana Dali x .9, Gatun formation. .
Marginella evax n. sp. x .8, Gatun formation. 270
Marginella cf. cineracea var. quadriplicala Böse x .8,
Recent. 271
6o. Oliva cf. litterala Lamarck x .85. Recent6i. Otiva callosa n. Sp. X .8, Recent. 271
62. Cancellaria karrisi Mauryx .8, Gatun. 272
294
Li Miocene ' Receit Moilusca of Panama Bay pl. VII
Explanation of
Plate VIII
29S
Plate VIII
Figure PageCa,sceUuia ¡aevescens Guppy x L, Gatun . . .
Tere,a gausa'aM ¡a.vifasci ola Maury x .85. Gatunformation 273
Terebra gaiusessis Mamy . var. x .8, Gatun 273
Terebra Macrospira n. sp. x .8. Gatun. 273
Tereb'a cj'acüenta U. sp. Ï Gatun 274
Terebra Lenuis, n. sp. x .75, Gatun formation 274D,illia ¡isosset1a Olsson x .8, Gatun formation . . . 274
Drilla zooki Brown and Pilsbry x .8, Gatun formation . 275
Drilla isaequistriala n. sp. x .8, probably Recent . . 275
Cossus imilato, Brown and Pilsbry X .9, Gatun . . . 275
296
Li .fiocene & Recent Mollasca of Panama Bay PI. l'if!
