126 PROCEEDINGS OF THE ACADEMY OP 



vexoinferiore, arcuato ; umbonibus parvis, depressis, obliquis, approximatis, 

 detorticatis ; ligamento elongato ; valvis tenuis, intus candidissimis ; cardine 

 angusto, inaequaliter tridentato ; dentibus cardinalibus obliquis minutis, medi- 

 ano et postico dente valvae dextrae bifidis ; dentibus lateralibus parum elon- 

 gatis brevibus. 



Long. 46 ; lat. 42 ; diam. 22 mill. 



Hah. Borneo. (Collect. Prime.) 



This light and delicate species seems different from any other that has 

 come under my notice. 



3. Cyrena regularis Prime. C. testa ovato-rotundata, tumida, cordi- 

 formi, valde inaequilaterali ; epidermide viridi vestita ; latere antico acuto, 

 postico subtruncato, latere supero posticali sulco sinuoso decurrenteseparato; 

 umbonibus tumidis, brevibus ; ligamento angusto ; valvis intus albis ; car- 

 dine utroque latere tridentato ; dentibus cardinalibus obliquis, mediano et 

 postico dente valvae dextrae bifidis ; dentibus lateralibus brevibus, antico 

 erasso, conico, apice acuto. 



Long. 78 ; lat. 69 ; diam. 40 mill. 



Hab. ? (Collect. Prime.) 



Somewhat similar in general, appearance to the Cyrena Caledonica 

 Garsies ; it is, however, anteriorly more angular, the body of the shell is 

 more inflated, the beaks are more prominent, and the epidermis is smoother 

 and more regular. 



4. Cyrena Siamensis Prime. C. testa ovato-transversa, subtrigona, in- 

 aequilaterati, convexa, postice subtruncata, antice valde declivi, crassa, solida, 

 in medio convexa ; epidermide fusca indnta ; irregulariter striata ; valvis 

 intus albis ; umbonibus depressis, brevibus, saepius erosis ; dentibus cardi- 

 nalibus tribus, obliquis, approximatis, fere parallelis, superne canaliculars ; 

 dentibus lateralibus subaequalibus. 



Long. 61 ; lat. 47 ; diam. 27 mill. 

 Hub. Siam. (Collect. Cuming et Prime.) 



Nearly allied to the Cyrena Sumatrensis Sowerby, from which it differs, 

 however, in being less inflated, smaller and generally less ponderous. 



5. Cyrena Bernardiana Prime. C. testa ovato-transversa, trigona, in- 

 aequilaterati, tumida, crassa, in medio ventricosa, margine superiore arcuato; 

 epidermide viridi vestita; regulariter striata; umbonibus parvis elevatis ; 

 ligamento elongato, partim infosso ; valvis solidis, intus candidissimis ; car- 

 dine angusto, inaequaliter tridentato ; dentibus cardinalibus angustis ; denti- 

 bus lateralibus elongatis. 



Long. 65 ; lat. 49 ; diam. 38 mill. 

 Hab. New Caledonia. (Collect. Cuming et Prime.) 



I dedicate this species to the Chevalier Bernardi of the Conchological Jour- 

 nal of Paris. 



6. Corbicula erosa Prime. C. testa trigona, subaequilaterali, tumida, 

 crassa, solida, transversim irregulariter striata ; epidermide nigrescente ves- 

 tita ; latero antico brevi, postico obtuso ; margine inferiore parum arcuato ; 

 umbonibus inflatis, erosis ; cardine incrassato, tridentato ; dentibus cardinali- 

 bus crassis ; dentibus lateralibus aequalibus, serrulatis. 



Long. 20 ; lat. 18 ; diam. 13 mill. 



Hab. Camboidia. (Collect. Cuming, Jay et Prime.) 



Compared to the Corbicula L y d i g i a n a Nobis, the only species to which it 

 seems at all allied, it is less elevated, not so triangular in appearance, its lines 

 of growth are less regular and deeper, its epidermis is darker and rougher. 



7. Corbicula b r u n e a Prime. C. testa ovato-transversa, subaequilaterali, 

 extremitatis aequaliter obtusa, transversim striata, sulcis regularibus ; epi- 



[June, 



