NELSON AND STANDEN ; HYALINIA PURA. 153 



L. E. Adams, in his ' Collector's Manual of British Land 

 and Freshwater Shells,' 1884, partially follows Jeffreys, and 

 describes the shell as ' dull, semi-transparent, light-horn colour.' 

 Var. iiiargaritacea — 'pearl white and nearly transparent.' Mr. 

 Adams informs us that he took the brown form as the type from 

 Jeffreys' work, but, as he did not observe any tinge of red, or 

 that the brown colour was on the upper side alone, he spoke of 

 the shell as he saw it. 



Rev. Canon Norman, in his ' Museum Normanianum ' 

 Catalogue, 1890, gives var. lenticularis Held; but in his 'Revi- 

 sion of British Mollusca ' (Annals of Nat. Hist., 1890), he does 

 not give any variety of H. piira. 



We consider that sufficient evidence has been produced to 

 warrant the expulsion of var. margaritacea Jeff, from our British 

 List, and if a varietal name is required at all, it should be given 

 to the brown form. The question of the relative frequency 

 between the brown and white form has, of course, nothing to do 

 with Alder's naming, and is simply interesting as pointing to 

 the appropriateness of his type being fully recognised. In his 

 ' Catalogue of the Mollusca of Northumberland and Durham,' 

 1848, Alder gives var. nitidosa Fer., and he evidently believed 

 the brown form to be nitidosa of that author. Gray evidently 

 did not agree with this ; and Jeffreys in 1829 put nitidosa as a 

 variety of H. cellaria. On consulting Ferussac's work we can 

 find no description of nitidosa, and Moquin Tandon, as already 

 shown, quotes it without giving any characters. But Ferussac 

 says ''Helix nitidosa nohis^=Ileiix nitidula var. x ' (Drap., Hist., 

 pi. viii., fig. 21 — 22). This is extremely conflicting, otherwise 

 we would have suggested var. nitidosa as a fitting name for the 

 brown form, to take the place of var. margaritacea Jeff. 



