MOLLUSCA. 65 



Family — Caediace^:. 

 Caedita. Bruguihres. 



270. Caedita dbyssicola, (Plate XIX. fig. 3.) Testa crassa, retusa, convexa, gibbosa, alba, 

 costis numerosis radiantibus ; costis rotundatis, minute lamellosis ; lunula late cordata; intus 

 lactea. 



Inhab. Straits of Malacca. From a depth of upwards of a hundred fathoms, 

 among mud. 



Family — VeneeacejE. 

 Venus. LinruEus. 



271. Venus Kellettii, (Plate XIX. fig. 5.) Testa oblique cordata, solida, laevigata, castanea, 

 transversim sulcata, seu potius lineis impressis exarata, intervallis latitudine variabilibus, ad extreme- 

 tates laminis munita; lunula elongate cordata. 



Inhab. Island of Quibo, "West coast of Veragua. In adhesive mud of a low 

 temperature, in between thirty and thirty-four fathoms. 



The specific name is a compliment to Captain Henry Kellett, R.N., C.B., 

 who, during the expedition, commanded H.M.S. Starling, and is conspicuous for 

 his attachment to science. 



Cytherea. Lamarck. 

 Subgenus Trigonella. Conrad. 



272. Cytherea crassatelloides, Conrad, Journ. Acad. Nat. Sciences, Philad. vol. vii. p. 253, 

 (Plate XXI. fig. 1.) 



Inhab. San Diego, California. On a mud bank in the harbour. 



It is unquestionably a satisfaction to be enabled to bring a fine shell like the 

 present into more general repute, and to introduce it to English collections. This 

 is one of a group of new shells brought from California by Mr. Nuttall, and 

 described in 1837 by Conrad. Very recently a number of shells from the same 

 coast have been described by M. Deshayes in the " Revue Zoologique," and 

 apparently in ignorance of the labours of the former ; hence some species have 

 been redescribed. The subgeneric designation of Conrad has been in previous 

 use as early as 1778 by Da Costa in his British Conchology ; and some kindred 

 words have been scarcely less happy, as Trigona of Schumacher has been 

 employed in Entomology, and Trigonia of Bruguieres likewise in Botany ; but 



