252 VALLONIA. 



Var. ALTILIS Sterki. PL 32, figs. 14, 15, 16, 17. 



Differs from the type by its somewhat larger size, more elevated 

 spire, narrower umbilicus, the last whorl descending below the 

 periphery of the penultimate. The aperture is even less oblique and 

 inclined, rather higher than wide, and the peristome quite straight 

 and simple. 



Alt. 1'7, greater diam. 2*9, lesser 2'5 mill. 



Drift on Main river, Germany, and Aare river, Switzerland. 



The few examples of this species extant are, though found in 

 drift and dead shells, quite fresh ; and it is to be expected that living 

 ones will be found in the localities given. 



(2) Group of V. pollinensis. 



Aperture crescentic circular ; surface very finely striated, with 

 more distant, acute, lamelliform, fine ribs. 



V. POLLINENSIS Paulucci. Unfigured. 



Shell with a rather narrow, funnel shaped umbilicus (the same at 

 the aperture little and gradually widened), convex, with obtuse 

 prominent apex, light horn colored, exceedingly finely striate, 

 adorned with more distant, acute, lamelliform, regular, fine ribs; 

 whorls 4J, regularly increasing, convex, with impressed suture, the 

 last gradually [slowly] increasing and not expanded at all at the 

 aperture, rather constricted, scarcely wider than the penultimate, 

 slightly and gradually descending above; aperture little oblique, 

 crescentic-circular, descending [?] ; margin straight, simple ; only 

 the columellar margin high up somewhat everted. 



Alt. 1-5, diam. 2'5 mill. ( Westerly 



Italy ; Monte Pollina, Prov. Potenza. 



Hel. pollinensis PAUL., in WESTERLUND, Fauna, I Suppl., p. 120. 



Description translated from Westerlund, I. c. Not seen by me. 



(3) Group of V. cosiata. 



Aperture with margins much approximating, nearly circular or 

 transversely wider, with a more or less strong lip ; surface with dis- 

 tinct membranous ribs ; nucleus with fine revolving lines. 



V. COSTATA Miiller. PL 32, figs. 18-22, 27 ; pi. 33, fig. 54. 



Moderately umbilicated, more widely so for the last half whorl, 

 depressed convex above, or nearly flat ; grayish to light or reddish 



