178 JOURXAL OF CONCHOI.OGY, VOL. II, NO. 6, APRIL, I905. 



year, at the sale of the late Mr. Hugh Nevill's collection, at Stevens' 

 auction rooms ; this wa,s from Ceylon. It resembles the example in 

 the British Museum (Natural History) in being almost an albino, but 

 the shape more oblong and laterally compressed than in C. vibex, and 

 the outer lip are identical in all three. As yet, I know of no other 

 examples extant. (5) C. turgida Reeve, quoted on Adams' list, is 

 referred to C. achatina by Tryon. I think it should be placed here. 

 It is a large, more inflated form, with decidedly ventricose whorls than 

 is usual, affording it subspecific characters, with the whole edge of the 

 inner lip denticled, the teeth somewhat variable. It is just possible 

 C. glabrata Dunker may be a form of this rather than of typical vibex. 



Lastly, C. tenuilabris Menke, 1828, is unknown to me. It is entered 

 in Paetel's catalogue as belonging to the sub-genus Casniaria, and 

 reported from Javanese waters. C. quadrata Link, mentioned (4) in 

 Adams' list above, I have likewise, so far, failed to identify. 



The following is a summary of the conclusions just arrived at : — 



CASSIS (Ivlein) Lamarck. 



Sub-genus Casmaria H. and A. Adams, 1853. 



1. C. achatina Lamk. 



var. pyriini Lamk. (sp.). 

 var. paucirugis Menke (sp.). 

 var. ceylanica Lamk. (sp.). 

 lA. ? Sub-sp. sophiae Brazier (sp.). 



2. C. vibex L. 



var. erinacea L. (sp.). 



var. torquata Reeve (sp.). 

 2A. Sub-sp. turgida Reeve (sp.). 

 2B. Sub-sp. ? glabrata Dunker (sp.). 

 2C. Sub-sp. kalosmodix Melvill (sp.). 

 Species vel varietates incertfe : 



C. quadrata Link. 



C. tenuilabris Menke. 



Opercula of Bithynia tentacu lata.— Messrs. Dean and Jackson in their pajier 

 on " A Chara and Shell-Marl Deposit at Haweswater " {antea p. 148) mention that 

 in one or two cases the deposit on the beach consisted entirely of opercula of 

 Bithynia lentaculata. This reminds me that in July, 1903, I visited Lou^h Gur, 

 Co. Limerick, and found the shore in one place white with opercula of this species. 

 At various other points along the shore a belt of foamy scum had drifted to the edge 

 of the lough, which, when examined, yielded myriads of opercula together with a 

 few dead shells of the species, and a few empty shells of Valvata (liscinalis and 

 Platiorbis (ontortus.—h. L. Mk'&'AY {Read before t/ie Society, Feb. 8th, 1905). 



