1908. Phii,i,tps. — Vertigo moiilinsiana^ Dtipiiy. 9 1 



being blown to the edge of the water they quickly crawled 

 out of it, carrying their shells in an upright position. Most 

 of the shells have only four denticles, but some of the older 

 specimens possess an additional small one at the corner of 

 the lip near the columella. 



The first specimens I collected differed from English 

 (Bishopstoke, Hants) ones in my collection in being of a much 

 darker colour and possessing a more contracted mouth and 

 rather narrow^er lip-margin, so I sent some to Dr. Scharff, who 

 compared them with English and Italian ones in the National 

 Museum, and at once pronounced them true V. mo7iHnsiana. 

 This determination w^as afterwards fully confirmed by Messrs. 

 R. Standen and J. Wilfrid Jackson, of Manchester Museum. 



The distinctions noted above between the Irish and English 

 specimens induced Mr. Standen to go deeply into the ques- 

 tion, and comparison with the numerous sets from nearly all 

 its known localities, British and continental, in his own col- 

 lection and in the collections of the Conchological Society and 

 Manchester Museum, resulted in showing that these differences 

 were fully accounted for by the "locality variation " to which 

 most species of mollusca are subject. This was clearly demon- 

 strated b}- a number of beautiful photo-micrographs prepared 

 by Mr. Jackson, who has kindly allovv'ed me to reproduce some 

 of them here (Plate 3.). A fairly large gathering made at 

 Tinnahinch in January proves that even among individuals of 

 one locality a considerable amount of variation may occur, 

 many specimens showing differences in size, outline of lip and 

 tumidit}^ This is well illustrated in Plate 3 and in the 

 accompanying figures (see next page), 



V. moiilinsia7ia has, like many other species, been described 

 by various authors under different names, and the synonjmiy 

 here published, I believe for the first time, will, it is hoped, 

 prove useful to conchologists. 



Dr. Scharff, who kindly worked out its distribution for me, 

 says that V. moulmsiana seems to be a member of the Lusi- 

 tanian fauna. It occurs in Spain, France, North Italy, 

 Carinthia, Sicily, and as far east as the Caucasus. North- 

 eastward it spreads into Switzerland, Germany, Belgium 

 Denmark, and northward into the. south of England and 

 Ireland, 



h 2 



