O S T R /E A. 



Pi„Mi; XXVI. 



Species Ki. (Fig. <i, l>, c, Mils. Ilatilcy.) 



OsTRiE.v GuiNEENsis. Onl. tculd mulci/oriid, vavie tov- 

 tuosd, j)leramqiie oblonyd, soltdiusculd, soixlide 

 alba, suhlamellosd ; inlics viridi, margine inliis 

 denlicuiato et indentato; impressiune musculari rcni- 

 formi ; cardine parvo, trigono ; apice acuminato. 

 The Guinea Osti!.«;a. Shell multiform, variously 

 tortuous, generally oblong, rather solid, dull 

 white, rather lamellose; green within, margin den- 

 ticulated and indented within, muscular impression 

 renilbrm ; hinge small, ti-igonal, apex acuminated. 

 DuNKEU. PL 43. f. 12-18. 

 Uab. Guinea. 



This little species assumes various t'ornis, e.xhibits no 

 external painting, and is always tinted with green in- 

 side. 



Species 63. (Mus. Hanley.) 



OsTH.SA LUGumus. Ost. testd teiwi, oblique subtrigond, 

 leviter aunculatd, griseo-purpured, obscure radiatd, 

 siiblcevigatd, nitenti, intus albidd ; latere antico ad 

 marginem ventralem producto ; valvuld superiori 

 complanatd, suboperculari, valvuld inferiori con- 

 vexd obscure costellatd ; ad marginem alteram 

 valvam xuperantc, cardine angusto dongato acu- 

 minato ; impressione musculari nni/ornii nigreti- 

 centi. 



The luguhrious Ostr.sa. Shell thin, obliquely subtri- 

 gonal, sliglitly auriculated, greyish purple, ob- 

 scurely rayed, rather smooth, .shining, whitish 

 within; anterior side produced at the ventral mar- 

 gin; upper valve flattened, subopercidar, lower 

 valve convex, obscurely ribbed ; at the margin ex- 

 panded beyond the iipper valve ; muscular im- 

 pression reniform, nearly black. 



SoWERBY. 



Uab. North America? 



.Species i; I. (Fig. a, h, Mus. Ilanley.) 



OsTi:/EA ciiicii.MSUTtTS. Osl. tcstd ovato-obloiigd, ple- 

 rumque augustd, ad rhizoporas adhceraiti, ad mar- 

 ginem jjlicatd, albidd vel pwpured ; intixs albd, 

 purpurea aut viridi tiiwtd, margijie valvules supe- 

 rioris omnino denticulato, valvidm inferior is inden- 

 tato. 



The stitched Ostr.jea. Slu'll ovately oblong, generally 

 narrow, adhering to mangroves, plicated at the 

 margin, whitish or purplish ; within white tinted 

 with purple or green ; margin of the upper valve 

 denticulated in every part, and that of the lower 

 valve indented. 



Gould. United States Expedition. 



llab. Massachusetts ? 



This species is named from the stitch-like appear- 

 ance of the denticles and corresponding indentations in 

 the inner margin of the valves. 



Species Oo. (Mus. Hanley.) 



Ostr^ea Algoensis. Ost. testd, suborbicidari, ventri- 

 cosd, subauriculatd ; valvuld superiori convexd, 

 superne nitenti, versus marginem dense squamosd, 

 valvuld inferiori extus subconcavd, irregulariter 

 tubefrculatd, albd ; valvulis intus albidis, impres- 

 sionibiis muscularibus maximis, reniformibus, con- 

 cenlrice viridi strigatis. 



The AL(i0A Ostr.ea. Shell suborbicular, ventricose, 

 subauriculated; upper valve convex, shining above, 

 closely squamiferous towards the margin ; lower 

 valve rather concave outside, irregularly tuber- 

 culated, white; valves whitish within, muscular 

 impressions very large, kidney-sliaped, concen- 

 trically striiicd with green. 



The spocinun is si regularly jjrodi 

 side. 



the anterior llah. Ala 



September, \>^~ \ ■ 



