NOTE ON CYPR^A VENUSTA, (SO WERE Y). 

 By James C. Cox, M.D., F.L.S. 



(Plate XV., figs. 1 and 2). 



The specimen of Cyprcea venusta, Sow., (= C. Thatcheri, Cox) 



from which the accompanying illustration was taken, was obtained 



at Cape Naturaliste, where it was washed on shore with the 



animal in it. It is 78 millimetres long and 52 wide. It is so 



unlike the type specimens that when first I saw it lying in a case 



of exhibits in the Melbourne Exhibition I mistook it for Cyprcea 



thersites, having a view of its dorsal surface only, but a moment's 



handling of it at once revealed its nature, unlike as it was to the 



type. Its base is white gradually passing off to a granular grey 



at the sides with rather large undefined round dark spots showing 



through the grey sides, which are absent in my two type specimens 



of C. Thatcheri ; the size of the teeth, their number and their 



character, however, in no way differ from them. The colour 



of the interior of the shell is of a darker purple than m my types ; 



but the anterior and posterior notches are similar. It is 



on the lateral and dorsal aspects of the shell that the main 



differences exist, and these differences after all are only differences 



of colour, — the granular slate-coloured sides meet in front and 



behind, in front of the channels, and thus form a complete circle 



round the shell, and the dorsal surface enclosed is ornamented 



with very dark geographically bounded, variously shaped portions, 



mostly rounded with tapering offshoots, while the intervening 



spaces are of the normal bluish-amber colour of the type of C. 



Thatcheri : the dark geographically bounded portions are quite as 



dark as the dark dorsal markings of an ordinary G. thersites. 



