HAAS: ABIDA AND CHONDRINA. 283 



as it flows iii the Pyrenees, and to its right tributary the 

 Valira, which flows out of Andorra. In the Pyrenean valleys 

 further west, no species of the affinis group could be detected ; 

 in those towards the east the above-mentioned A. a. catalonica 

 (Bof.) lives. 



Genus CHONDRINA (Vol. XXV, p. 1). 



Chondrina (Solatopupa) similis (Brug.). 



Pilsbry, Manual XXV, p. 57, pi. 4, figs. 1-4. 



As Pilsbry has said, this species has its southeastern limit 

 in the Spanish Province Gerona, wherein it occurs southward 

 as far as the Ter, thus about to the boundary of Province 

 Barcelona. Only the locality Fonteta lies south of this river. 

 Couturier's record that C. similis occurs in Barcelona could 

 not be confirmed by Bofill and me, at least not in case the city 

 of that name was intended. According to Spanish usage, the 

 Province is called by the name of its capital city, so that quite 

 possibly Couturier's material came from Barcelona Province. 

 Though similis is not yet detected there, yet it is by no means 

 excluded that it does not live in the northern part, over 

 against Gerona Province. 



The variability of Spanish specimens is relatively small, at 

 least as compared with those of the Alpes-Maritimes. 



Subgenus Chondrina proper. 



This includes all of the species following. 



The group of Chondrina (Chondrina) bigorriensis (Des M.). 



As in A. affinis among the Abidas, so C. bigorriensis here, 

 has formed a series of local races, which however are less dis- 

 tinct owing to the greater variability of the species. Only in 

 the average can the specimens of a special district be said to 

 be characteristic thereof. Among them there are always scat- 

 tering specimens which are not separable from the typical 

 form of the species ; so that one may venture to say that in 

 this species the formation of local races is not yet completed. 

 Since the size and thickness of the shell fluctuates between 



