JOURNAL OF CONCHOLOGY, 255 



CRITICAL NOTES ON SOME LAND AND 

 FRESHWATER MOLLUSCA. 



By T. D. a. COCKERELL, M.C.S. 



(Read liefore the ConchoIosii:al Society, April 2n(:l, 1S90). 



Through the kindness of Mr. J. A. Singley, of Texas, I have 

 been enal:)led to examine a large series of shells, most of which 

 are not well known to British Conchologists. I have thought, 

 therefore, that a few notes on some of these specimens might be 

 of interest, especially in relation to synonymy. The German 

 shells were mostly collected by Mr. Jetschin, and there is reason 

 to suppose that with a few possible exceptions they are correctly 

 named. I give the names and localities as received, and follow 

 with my own notes. 

 Zonites nitens var. albina Kob. Hochwald, Austria. The 



greenisli-white form oi nitens; max. diam., lo mill. 

 Z. nitens var. beryllus West. Patschkau, Germany. A 

 distinct var., small (max. diam., 7 mill.) more compact and 

 rounder; colour, transparent white. Agrees with nifidulus 

 rather than nitens. 

 Z. glaber var. striaria West. Hochwald. A fine shell, 

 certainly i^labra Jeff. Max. diam., iiA mill.; yellowish 

 horn, semitransparent, very shiny; flattish. Aperture more 

 semilunar than usual ; umbilical region hardly whitish. 

 Resembles the Cheshire form of H. glabra more than the 

 south of England form. 

 Z. crystallinus var. subterranea Bgt. Rudesdorf, Ger- 

 many. Seems to differ only in not being so flat, shell 

 altogether rounder. 

 Vitrina nivalis Charp. Weissenbach, Tyrol, Austria. So far 

 as the shell goes, this is a good deal like Vitrittosofiifcs of 

 America. V. kochii Andr., from Patschkau, seems hardly 

 more than a variety of nivalis. 

 Helix pomatia var. connpacta Hazay, Tirchova, Hungary. 



