BIVALVE SHELLS. 221 



vis ; dentibus cardinalibus duobus utraque valva ; lateralibus 

 lamelliformibus, perpendiculariter striatis,quatuor valva dextra, 

 duobus sinistra. 



Cyrena Panormitana, Bimna, Nuovi Mollus. Terrest. di Palermo, 

 p.21. 



Hab. In rivulis Siciliae. 



b. Species Africance. 



2. CORBICULA CONSOBRINA. 



C. testa ovato-trigona, transversa, inaequilaterali, tumida, sub- 

 cordata, fusco-virente, transversim tenue sulcata ; latere antico 

 longiore, lato, obtuso, postico valde declivi, brevi, subtruncato ; 

 umbonibus tumidis, obtusis, oppositis, apice denudato viola- 

 ceis, valvis intus albo-pallide violaceis, ad margines saturati- 

 oribus ; cardine angusto in utraque valva tridentato, dente 

 postico valvffi sinistrse obsoleto ; dentibus lateralibus angustis 

 inaequalibus, antico longiore, cardinem attingente. 



Cyclas consobrina, Caillaud, Voy. a Meroe, ii. pl. 61. f. 10, 11. 



An eadem var. ? Savigny, Exj). d'Eg. Moll. pl. /• f. 7- 

 Hab. Flumen Nilum. 



3. CORBICULA COR. B.M. 



C. testa elongato-trigona, cordata, subaequilaterali, tumida, viridi- 

 fuscescente, trausversim tenue et subtiliter sulcata ; umboni- 

 bus prominentibus, involutis, vix obliquis, saepius integris ; 

 lateribus obtusis, posticali paulo breviore, subtruncato ; valvis 

 intus violaceis zonulis saturatioribus ornatis ; cardine angusto, 

 tridentato; dentibus subffiqualibus, posticali valvula dextva 

 apice emarginato ; valvulai sinistrse mediano bifido ; dentibus 

 lateralibus angustis, tenue striatis. 



Cyrena cor, Lamk. An. s. Vert. v. 552. no. 3. 

 Deless. Rec. de Coq. pl. 7- f- 7- 

 Hab. ? exoriente {Olivier). In Nilo superiore, Coll. Cum. 



4. CORBICULA PUSILLA. B.M. 



C. testa parva, tenui, turgidula, ovato-orbiculari, vix trigona, in- 

 ajquilaterali, alba ; striis transversis, confertis ; epidermide 

 pallide flava ; deutibus lateralibus elongatis, striatis, cardinali- 

 bus tribus, inaequalibus, duobus majoribus in utraque valva 

 bifidis. 



