C Y T H E R E A. 



Plate VII. 



Species 24. (Miis. Cuiiiiiig.) 



Cythedea DiLLWYiNi. Cijlli . tedd tngono-ciineiformi, 

 conipre-ssiiiscidd, subreqidlatcrali, spudiceo-fuscd, vio- 

 lacM-fi(sco fallid'!'. radlatd et concentrice fasciatd, ht- 

 uiild snbampld, obloiigo-ocalL 



Dillwyn's Cytherea. Shell ti-iaiig'ularly wedge-shaped, 

 rather compressed, nearly equilateral, iawn-browii, 

 faintly rayed and concentrically banded with violet- 

 brown, lunule rather large, oblong-oval. 



(^'uUirrfn viaclroldes, Sowerby (not of Lauiarek), Thes. 

 vol. i. p. (il5. pi. 128. f. 3(1. 

 Trigona Dillwi/iii, Deshayes. 



llnlj. Indian Ocean. 



A solid, Donax-shaped sliell, neatly cross-lianded and 

 raved with violet-brown. 



with two ratlier distant black or brown rays, smooth, 

 shining, lunule indistinct. 



Hnh. 



Allied to C. casta, but of a more gibbous, heart-shaped 

 ibrm, distinctly produced at the posterior side. The two 

 distant rays of black or brown are striking, but they may 

 not be permanent. 



Species 25. (Mas. Cuming.) 



Cytiiere.\ casta. Ct/th. testa ocald, vix curdatd, sub- 

 depressd, solidiuscidd, glaucescente-grised, pallidissime 

 radiatd, lavigatd, iiitente. 



The chaste Cytherea. Shell ovate, scarcely heart- 

 shaped, somewhat depressed, ratlier solid, glaucous- 

 grey, very faintly rayed, smooth, shining. 



Fenits casta, Chemnitz, Conch. C.b. vol. vi. p. 349. pi. 33. 

 f. 34fi. 



Cytherea casta, Lamarck. 

 Meretrix casta, Deshayes. 



Hab. Ceylon. 



The shining glaucous-grey colour, indistinctly rayed, is 

 a characteristic feature of this species. 



Species 2(i. (Fig. a, b, Mus. Cuming.) 



Cytherea astricta. Cyth. testa subtrigmio-cordatd, 

 glbbd, solidd, postice subproductd, olivaceo-spadiced, 

 riifo iinctd, radiis diiobus subdlstaiitibus nigris aid 

 fuscis notatd, laoigatd, nitente, liinuld Indist'mctd. 



The tied Cytherea. Shell somewhat triangularly 

 heart-shaped, gibbous, solid, slightly produced pos- 

 ti-riorly, olive-fawn colour, tinged with red, marked 



Species 27- (Mus. Cuming.) 



Cytherea radiata. Cijtii. testa trigouo-uvatd, poslkl- 

 siibprudiietd, solidd, gibbosd, Jidrescente, riifesceiite- 

 brunueo profase radlatd et cunceiitrice J'asciatd, treiu- 

 gatd, hand niteide, antice subpHcato-cornigutd, epider- 

 mide Kuriwd partlni indutd, lunula ampld. 



Tnii RAYED Cytherea. Shell triangularly ovate, rather 

 produced posteriorly, solid, gibbous, fulvous, pro- 

 fusely rayed and concentrically banded with reddish- 

 brown, smooth, not shining, obscurely plicately 

 wrinkled on the anterior side, partially covered with 

 a horny epidermis, lunule large. 



SowEKBY, Pro. Zool. Soc. 1835, p. 23. 

 Veiins Salaiigensis, D'Orbigny. 

 Cytherea gracdior, Soweiby. 

 Trigona Byroitensis, Gray. 

 Trigona radiata, Deshayes. 



Hab. Salango and Xipixapi, West Columbia (in sandy 

 mud, at the depth of nine fathoms) ; Cuming. 



Of a solid, triangular form, obscurely plicately wrinkled 

 on the anterior side, profusely rayed with light red-brown, 

 not shining, but partially covered with a horny epidermis. 



Species 28. (.Mus. Cuming.) 



Cytherea nubila. Cyth. tesid trigono-cordatd, gibbd, 

 prfPsertini ad latus posticuni,fidvd, pallide Jusco pro- 

 fuse undutd et fasciatd, Icevigatd, nitente, ared posticd 

 perampld, lata, plana. 



The cloudy Cytherea. Shell triangularly heart- 

 shajied, gibbous, especially on the posterior side, 

 fulvous, profusely waved and banded with light 



anuary, 18(54. 



