162 THE VOYAGE OF H.M.S. CHALLENGER. 



This well-known "West Indian shell has already been recorded from several islands 

 belono-ing to that group and from St. Elena and Monte Christe on the west coast of 

 Central America. The shell described by Reeve as Cardium hiulcum, from an unknown 

 locality, is unquestionably a mere distorted half-grown example of this species. In the 

 Report on the Mollusca of the west coast of America, Dr. P. P. Carpenter states that he 

 considers Cardium asperum perfectly distinct from Cardium hullatum. In this opinion 

 I cannot concur, for, having closely studied the two forms, I fail to discover any con- 

 stant and sufficient reasons for separating them specifically. 



Cardium (Papyridea) semisulcatum, Gray. 



Cardium semisulcatum, Gray, Annals of Philosophy, 1825, vol. ix. p. 137. 



Cardium 7-riirjiculnm, Sowerby, Proc. Zool. Soc. Lend., 1848, p. 106. 



Cardium ringicidum, Sowerby, Conch. 111., fig. 11. 



Cardium ringiculum, Hanley, Rec. Biv. Shells, p. 136. 



Cardium ringiculum, Reeve, Conch. Icon., vol. ii. fig. 115. 



Cardium ringiculum, d'Orbigny, Sagra's Hist, de Cuba, vol. ii. p. 305. 



Cardium {Papyridea) ringiculum, Romer, Conch.-Cab., ed. 2, p. 76, pi. xiL figs. 17, 18. 



Cardium petitianum, d'Orbigny, op. cit., p. 309, pi. xxvii. figs. 50-52. 



Habitat. — Simon's Bay, Cape of Good Hope, in 15 to 20 fathoms. 



Gray's name has hitherto been overlooked. In the British Museum the types which 

 he described are stUl preserved, and accord with respect to colour with his brief 

 diagnosis. They consist of five odd valves, one of them being totally white, two pale 

 lemon-yellow, the fourth light red, and the remaining specimen white anteriorly and 

 pink behind. 



I am inclined to think with Reeve that this species does not occur at Ceylon as 

 stated by Sowerby, but that it wUl be found restricted to the Atlantic. It is very 

 interesting to find this West Indian form ranging eastward as far as the Cape. 



Cardium (Papyridea) transversale, Deshayes (PL VIII. figs. 3-36). 



Cardium transversale, Deshayes, Proc. Zool. Soc. Lond., 1854, p. 333. 



Habitat. — Station 75, ofi" Fayal, Azores, at a depth of 4.30 fathoms; and ofl' 

 Tenerife, Canary Islands, in 70 fathoms (Challenger) ; Alboran Island (Deshayes). 



This species, as far as at present known, is of small size, the largest specimen 

 examined being only 6 mm. long, 4 high, and 3 in diameter. It is oblong, rounded 

 anteriorly, and obliquely truncated behind. It is very inequilateral, white in front and 



