1849. J occurring in Afghanisthan. 655 



Fresh Water Shells. 



Fam. Paludinidve. 

 1 1 . — Paludina parvula, (Hutton.) 



Animal dusky grey. 



Shell convid, of four whorls exclusive of apex ; colour of epidermis 

 dull or dusky green ; aperture ovate, rounded below, angular above ; 

 oblique ; operculum horny ; subumbilicate, pillar lip partially reflected ; 

 sutures deep ; epidermis of the upper whorls usually eroded ; trans- 

 versely striated by fine lines of growth. Length T \ of an inch, or less. 



Inhabits a marshy patch of ground caused by a spring oozing from 

 the side of the Kojuck Pass, at Chummun. 



Fam. Limn^ead^. 



12. — Limncea peregra, (Lam.) 



This so closely resembles one of the varieties of the European shell, 

 that I can see no good reason for separating it. On comparing it with 

 an English specimen long since presented to me by Mr. Benson, no 

 character appears to authorize the idea of its being other than a mere 

 variety, and the differences, where any exist, are nothing more than 

 the variations usually observable in a series of specimens. In fact the 

 only difference that I can see, consists in the spire of the Candahar 

 shell being rather more exserted than in the European specimen before 

 me, — but in this respect, judging from Gray's figures and description, 

 there is always great variety, and consequently no importance can be 

 attached to it. At Candahar the species was very common in brick 

 tanks, and almost invariably covered with small aquatic plants or 

 incrustations of lime, concealing the colour, and sometimes even the 

 shape of the shell, a fact which is likewise observable in regard to the 

 European species. 



Var. A. — Low down on the Western side of the Kojuck range of 

 hills, at some distance below the Pass, is a green spot called Chummun, 

 from whence issues a small clear spring of water, which spreading 

 over the slope, forms a marshy patch in which are several species of 

 shells, and among them occurs another variety of Limncea peregra, 

 which living in running water is free from the impurities which attach 

 to the Candahar variety, and the substance of the shell is perhaps 

 somewhat thicker. 



