S T R yE A. 



Species 41. (Fig. a, Mus. Hrit.; A, 



Ml 



llaniey.) 



OsTR.EA FROSS. O^t. leM jUiwcd, tc iiui uscnld, pleriim- 

 que laid, per lohas testaceas ad radices adhwrenti, 

 suhpwjmreo-fitscd^ divwicatim plicatd, plicis ad 

 marginem magnis, acutangnlai-ihus ; intus pallida 

 snhaureo-fidrd, cardlne valves sinistrce parvA. 



The leaflet Osti:.*:a. Shell I'oliiicoous, rather thin, 

 mostly broad, adhering to routs liy sliclly lobes, 

 purplish brown, divergently plicated; plications 

 large, sharply angtilar at the margins ; inside pale 

 golden fawn; hinge of the loft valve small. 



LiNNiEUS. Syst. Nat. 



Ostrma limacella, Lamarck. 



Ostrcea iiiMla, Lamarck. 



Ostrcsa EniceUa, Lamarck. 



Hab. West Indies. 



Differing from Ot^trmi fidiinn in the acutely angular 

 plaits ; and whereas it is the prevailing habit of the 

 0. Jhli urn to be attached lengthwise to the roots and 

 stems of seaweeds, the present species is generally 

 attached crosswise. 



Species 42. (Mus. Ilanlcy.) 



OsTr.^\ RETD.SA. Ost. testd elonyalA, tiiiijiiwformi, 

 tortuoso-wcuatd, solidd,coni:entrii'i lamimitd, alhidd, 

 pvrpureo tincto, intus albd, jivr/nirvn-iii/n.^'nit, 

 vei-sus marginevi ventralem sv/i/.-ni : nniriiiiiiliiiK 

 lateralibuslevitev crenulatis ; inijm .<sioii, imixi-iilari 

 elongatd ; cardine lata, ntrdipie valcd produdo ; 

 valvd inferiori perfoliaced. 



The obsolete O.str.ea. Shell elongated, tongue- 

 shaped, tortuously arched, solid, concentrically 

 laminated, whitish tinted with purple, white within, 

 suffused with reddish purple near the ventral 

 margin ; lateral margins slightly crenulated ; 

 muscidar impression elongated ; hinge wide, pro- 

 duced in each valve ; lower valve very foliaceous. 



Pease. ? 



Il,d,. Sandwich Islands. 



ind only in a half- fossil state. 



This shi 



Species 43. (Fi 



OSTE.EA CJUERCINfS. Ost. 



nigatd, 



a, h. Mus. Hanley.) 



■rqfidanhr 

 d margin,,, pl>n,ld, con>,>n's,,l, obsrure 

 pitrpured ; valcd inferiori sidicnni/ilniKitd. supcrurri 

 ivnrt'jdlisculd ; intus querriimx, m, in/in,' albido, 

 striijato, findiriatn : iinjircssiuiii' iiiiisri(/<iri maxima, 

 cuncentrice utriijaln. 

 The oak Oystkk. Sliell suborliicular, irregularly 

 rugged, plaited at the margin, compressed, dull 

 purple ; lower valve rather flattened, upper rather 

 convex; within oak-coloured, margin whitish, 

 striped, fimbriated ; muscular impression very 

 large, concentrically striped. 



Hab. ? 



A remarkable shell in Mr. llanley's collection, which 

 I can assign to no known species. The oak-wood 

 colouring of the interior and the large size of the 

 muscular impression, are the distinguishing charac- 

 teristics. 



September. 1871. 



