OST H/EA. 



I'l-vii: XXIX. 



The 

 iservt 



Fig. 64, <•, Mus. Ta)- 

 inner denticulations of tlii? 

 .1, provH it to be a variety ol' 



not at first 



Ostrci-(. 



Species 7;>. (Fig. «. i, Mus. Taylor.) 



OsTU.K.l CY.MB^FOU.MIS. Ost. tCStd tCVUi, l'n/i(ir< d. <l lliii/.i. 



hic-illic purpurea fiiffusd, i-alde ina-ipiil'itrni!/. 

 lomiituiUnuliter attemiatd; rated inferiori pmj'irn- 

 f/issiiiid, cijmhiformi, cardine alleiiiiato, acute vunei- 

 fornii, apice acumhiato ; ralvd siipeiiori di'preffid, 

 aiinplanatd, vel excaratd, marijine (/or.-'dli rertiuscvlo. 

 tipire parvo, aciito. 

 'Vm iVMBlFORM OstHjEA. Shell thin, foliaccou.s, whitish, 

 here and there suffused with purpk', very inequi- 

 lateral, longitudinally attenuated ; lower valve very 

 deep, boat-shaped, hinge attenuated, acutely cunei- 

 form, ape.x acuminated ; upper valve depressed 

 llatteiied or e.xcavated, dorsal margin rather 

 straidit, ape.x small, acute. 



Species 74. (Mns. Ilanley.) 



R.T:.\ Ml-LTIST1!I.\TA. Ost. listd n„i,/,ns.-^,>, (/,'.<roid(V, 

 irrcyiilaritcr sxihrvtiinda ; riiira sii/iirion' fiisrd, 

 paulv conrexil. .v7r»> 7-a,/ia,itihiis ,1 ,/ir, r</,nti/>it.'^ 

 densis sculptd, /irajii uiiilmni's hrit, r t'di, icululd. 

 margine dor.'<ali i.rjxiiii:^, r, nlnili .-idii-i I'linlnUt ; 

 vxnbuiiibiis (iriiiiiiniitin, pain\< , rulrd infrrinri itlbd, 

 complanatd. 



MULTisTi;iATEr> OsTU.EA. Shell comj>ressed, dis- 

 coidal, irregidarly rather rounded ; upper valve 

 brown, a little convex. seul].tured with close 

 radiating and diverging stria-, slightly tubercular 

 near the umboes, dorsal margin expanded, ventral 

 .slightly crenulated ; undioos acuminated, small ; 

 lower valve white, flattened. 



l.KY. Pro. Zool. Soc, 1M4(J. 



A highly characteristic .shell, different in sculpl 

 )ni any other. 



Species 7.-). (Mus. Barclay.) 

 ■i;.i:a aifixis. O.v/. tc.<td Kolidd, 7-uf/oyd, purpurea, 

 /niiisci r.-«^ iiUi,iii/d. lid iiiartjinnit plicis mmjnis,(KUte 

 aihjiiliUis iniilatd ; tutus medio aureo-subfusrd. 

 iu<ir<jhie late purpurea, riratrice postice laterali, 

 luagud, cinered, cardine parvo, trigono, anfice Kub- 

 tenninaii : mari/ine iutenio 7itrdi/ue vaird, grami- 

 lato. 

 \: ALLIKI) OsTi;^A. Shell solid, rough, purple, 

 transversely oblong, undulated at tlie margin with 

 large acutely angular plica;; within golden 

 brownish, with the margin broadly purple, cicatrix 

 posteriorly lateral, large, ash-coloui'ed, hinge small, 

 trigonal, nearly terminal in front; internal mar- 

 gin granulated in each valve. 



.■KllliV. 



b. Diego (iarcia, near the Mauritiu.*. 



ient by .M. Uobilliart to Sir David Bai-clay, I>art. 



Species. 7C. (Mus. Taylor.) 



OsTR.KA FniRlliENSls. Osl. tcstd subarcuold, lowiitudi- 

 natiier svbatteuuatd, xolidd, i-alde incrquilatirali. 

 valrdinferiari ad marginrmplinitd. purjm rco siiffusta, 

 pradiirld, ad r/,;:.n/,h„r<iy adia'nuli, iiitiis ad mar- 



• 2"" J"" 



, I ulhd . 



vaird 



.<ujieri(iri paulo ronvcro, o/icrriili/w-iui, subiwrii/ata. 

 Till-: Florida Osthjea. Shell somewhat arched, longi- 

 tudinally rather attenuated, solid, very inequi- 

 lateral, lower valve plicated at the margin, 

 suffused with purple, produced, cicatrix chestnut 

 or white ; upper valve a little convex, opcrculifonii, 

 rather smooth. 



SoWEIHiV. 



Ilab. Coast of Florida. 



This is one of the Mangrove oysters, who.se form >o 

 much depends upon the position in which they are 

 attached. In both our specimens the lower valve rises 

 considerably beyond the upper. 



1871. 



