Quarterly Journal of Conchology. 1 33 



so intimately blended together by intermediate links as to make the 

 line of separation too critical, the test fails, and a subordinate group, 

 or a 'variety,' is the result.'' 



NOTE ON THE IDENTITY OF VARIOUS EUROPEAN 



HELICIDAE. 



By C. P. GLOYNE. 



Through the liberality of my French friends and correspondents, 

 especially M. de St. Simon and M. l'Abbe Dupuy, I have had the 

 opportunity of examining and comparing specimens of various re- 

 puted species, and I will briefly mention one or two conclusions I 

 have come to. 



Azeca Nouletiana, Dupuy, is a variety of A. tridens, Pult. The 

 British specimens in my possession all belong to this variety. 



Azeca Mabilleana, Fagot, is not even a variety; I cannot see any 

 difference between it and the typical tridens. 



Clausilia nigricans, Pult. I fail to perceive any difference be- 

 tween it and C. rugosa, Drap. Moquin Tandon says that the striae 

 in nigricans are closer than in rugosa, but I see no difference. All 

 the subvarieties — Reboudii, Dupuy; abietina, Dupuy; etc. — must 

 be sunk in the species rugosa, Drap. 



Ccecilianella acicula, Mull., Liesvillei, Bourgt., ang/ica, Bourgt. 

 These are absolutely identical, and I suspect that most of the other 

 so-called species of Ccecilianella must follow suit. 



Helix nubigena, Charp. This is a variety only, but of carascalen- 

 sis, Fer., not of cespitum, Drap. as Moquin Tandon says. 



Buliminus niso, Pfr. I suspect that two forms have been includ- 

 ed under this name, one only a variety of B. quadridens, Mull., but 

 the other more elongate and cylindrical, a distinct species. 



Clausilia Aleissneriana, Shuttl., Kiisteri, Rossm., adjaciensis 

 Shuttl. These are terribly alike. 



