1898.] Adams. — Hyalinia Drapaymaiidi in N. I7'ela7id} 83 



compare them carefully with individuals of what we know as 

 typical Draparnatidi from Tenby. Now while the general 

 appearance of the Irish animals tallies with those from Tenby, 

 the following differences appear when examined under a 

 lens. 



The animals from Tenby (like those from Exeter with 

 which I am acquainted) are a dark but brilliant cobalt blue, 

 while those from Murlough are more of an indigo colour. 

 This alone might be put aside as trivial, but the mantle of the 

 Irish specimens is alwaj^s speckled with dark brown like those 

 of the normal cellaria, whereas the mantles of the specimens 

 from Tenby are entirely without these dark specks. 



I also remarked that the Irish specimens lost most of their 

 dark colour when boiled, which w^as not the case with those 

 from Tenby. 



Not satisfied with all this I sent some of the Irish specimens 

 to Mr. W. Moss of Ashton-under-Lyne, who has had great 

 experience in photographing the radulae and genitalia of 

 numerous species, and especially of the Hyaliiiics. His 

 opinion is that both radulae and genitalia of the Lancashire, 

 Manx, and N. Irish specimens are nearer to those oi cellaria 

 than to those of the Draparnaudi from Tenby. 



(It may be remarked here that it is not quite certain if our 

 typical Draparnaudi from Tenby are identical with what the 

 continental authorities call by that name ; indeed there is a 

 doubt whether the continental authorities are unanimous). 



The size of the doubtful forms under discussion is remark- 

 able. Some Lancashire specimens that Mr. Moss sent me 

 for inspection measure from 12 to 13 mm. in diameter, while 

 I collected some from Murlough measuring 12, 13, and one 

 14 mm. The breadth of a large typical cellaria is 10 mm., and 

 that of Drapar7iaudi 14 mm. 



Taking all these facts into consideration, I am unable to 

 consider the Irish specimens as Draparnaudi, but am inclined 

 to think them a form of cellaria, though, of course, I do not 

 pretend to say that the real Drapar7iaudi does not exist in the 

 North of Ireland. 



Northampton. 



