CHONDRINA. 



79 



the other species, usually known as avenacea, he uses the name 

 clienta Westerlund, contrasting them thus. 



C. avenacea (Brug.) 



1. Shell surface irregularly 

 striate. 



2. Both principal palatals and 

 the infrapalatal almost 

 equally strong, the parietal 

 and columellar lamellae placed 

 opposite them. 



3. Only the upper whorls 

 strongly convex, the middle 

 and lower laterally com- 

 pressed. 



4. Last whorl usually strongly 

 flattened or even impressed 

 below the shoulder-like swell- 

 ing behind the aperture. 



5. Peristome little expanded, 

 weakly lipped, light brown- 

 ish ; interior of aperture more 

 or less reddish brown. 



6. Color of shell usually light- 

 er or darker reddish brown. 



C. clienta (West.) 



1. Shell regularly, finely 

 striate. 



2. Only the two principal 

 palatals strongly developed ; 

 super- and infra-palatals, if 

 present, very short and 

 receding. 



3. Middle and lower whorls 

 are also quite convex. 



4. Last whorl flatly convex, 

 but little flattened. 



5. Peristome distinctly ex- 

 panded, lipped, whitish; in- 

 terior light grayish brown. 



6. Color of shell usually 

 corneous brown. 



In distribution, according to Ehrmann, avenacea is mainly 

 western, from the Maritime Alps through the Swiss and 

 French Alps to the Alpenrhein. C. clienta is mainly east, as 

 far as the Caucasus, where a new race which is called [Chon- 

 DRiNA clienta] caucasica Ehrmann occurs (I.e. p. 19, foot- 

 note 1, pi. 1, fig. 4). It differs from the type by the more 

 elongate form, less regular striation, and an infrapalatal, 

 which is often stronger than the supra-palatal (PI. 20, fig. 4). 

 Type locality Letschghum, Caucasus. Unfortunately the var. 

 suhcereana West, of the western Crimea could not be 

 compared. 



