S T R JE A. 



specie 



(Fiir. (1, h, Mus. Ilanley.) 



OsTR^A COCHLEAR. Ost. lentd tenuisiimd, ovatd vel 

 suborhicidari, foliaced ; valvd inferiori profiin- 

 disstmd, alb& vel piirpureo strigatd, intus serpe 

 prope cardinem et medio vivide fused ; cardine 

 trigono ; valvd supenori compressA, margine rejkxo, 

 purjntred, prope marginem radiatiin strigatd. 



The spoon Ostu^.a. Shell very thin, ovate or sub- 

 orbicular, foliaceous ; lower valve very deep, 

 white or stripeil with purple, often a bright brown 

 within near the hinge and in the middle ; hinge 

 trigonal; upper valve compressed, with the 

 margin reflected, jmrplo, near the margin radiateiy 

 striated. 



Poll Utriusquo Sicila;, vol. ii. tab. 28, f. 28. 



Hah. Mediterranean. 



Remarkable for its thinness and diiith. 



Species 4G. (Mus. Ilanley.) 



! OsTU.KA rosacea. Ost. testd iiregulariter pUcatd, rugosd, 



\ subtiigond, roseo-purpurascenti, intils albd, margine 



nihro limatd ; valvd inferiori pirofundd., siiperiori 



j compressd ; cardine parvo ; impressione musculari 



mbrottindd, 2>(trvd. 

 The rosy O.STRiEA. Shell irregularly plicated, rough, 

 subtrigonal, purplish pink, interior white, with 

 margin red-bordered ; lower valve deep, upper 

 compressed ; "hinge small ; muscular iiufiressiou 

 rather round, small. 



I CuKMNiTZ (Parasitica var.). Conch, f. 997. 



' O.-itrwa pticatula var., Lamarck. 



1 Hah. Lord Hood's Island. 



I 



Species 45. (Fig. a, h, Mus. Ilanley.) 



OsTRA\ lima. OsI. testd pared, fused, longitridinaliter 

 subovatd, subceqiuvalvi, tenui, valvd iifiTiuri pro- 

 fumld, mimite striatd ; valvd superion subcomprcsi^d, 

 tubercidis parvis aaitimarginatis trigonis nigatd ; 

 cardine parro. 



The file Ostr.ea. Shell small, bro-wn, longitudinally 

 subovate, subequivalve, thin ; lower valve deep, 

 minutely striated ; upper valve subcompressed, 

 roughened with small .sharp- edged trigonal 

 tubercles ; hinge small. 



Sowerby. 



Mab. Sandwich Islands. 



The pecuUar rasp-like sculpture which roughens the 



upper valve in this interesting little species does not 



appear, as might at first be suspected, to be the resultof 



any structure in the substances to which it is attached. 



Species 47. (Fig. a, b, Mus. Hanley.) 



OstRvEA Chemxitzii. Ost. testd tcnvi, comphmatd, de- 

 pressd, plicatim et xmdulatim rugosd, pkrumque 

 sinistrorsd, ad margincs lobatd ; valvd superiori 

 sicbviridi, prope umbones obscuri purpureo ; margine 

 dorsali post umbones e.rpanso : vmbmiibus jJ'irvis ; 

 cardine lineari. 

 Chemnitz's 0.str.ea. Shell thin, flattened, depressed, 

 roughened with plaits and undulations, generally 

 sinistral, lobed at the margins; upper valve 

 greenish, dull purple near the umboes ; dorsal 

 margin expanded behind the umboes ; umbues 

 small ; hinge linear. 

 n.\NLEY. Proc. Zool. Soc, 1845. 

 Ilab. China. 



I understand by Mr. Hanley's expression "shell 

 generally sinistral," that whereas in most species the 

 ape.x is turned towards the posterior side as indicated 

 by the position of the adductor muscle, in this species 

 it is generally turned away from that side. 



September, 1871. 



