HAAS: ABIDA AND CHONDRINA. 289 



Azpeitia figures 8 specimens on his plate, representing as 

 many forms, and demonstrating their untenability. Among 

 the figured specimens happened to be one of A. b. tenuimargi- 

 nata form elongatissima Des M. from Foz de la Binies in 

 Aragon, 15.5 mm. in length. 



Chondrina bigorriensis microchilus (Bofill). PI. 26, fig. 10. 



Pupa leptochilus var. microchilus Bofill, Act. Mem. I 

 Congr. Nat. Esp. Zaragoza, 1909, p. 198 ; Treb. Inst. Cat. Hist. 

 Nat., I, 1915, p. 44, pi. 6, f. 2. 



Pupa (Mod/iceUa) megacheilos microchilus Bofill and 

 Haas, Est. II, p. 84, pi. 3, f . 1, 2 ; Est, III, p. 199. 



"This title is proposed for a form which I found in the 

 valley of the Noguera Ribagorzana and in the Congost de 

 Sabinos between Sot de Fet and Sot de Blancafort. 



"It is distinguished chiefly by its strongly lengthened shape 

 and its small aperture" (Bofill). 



From eight localities in Montsech there are specimens of a 

 form of bigorriensis before me which all differ from typical 

 bigorriensis and its local form tenuimarginata by the pecu- 

 liarities mentioned by Bofill. On pi. 26, fig. 10, is figured a 

 Bofill cotype of his P. microchilus from Ca'n Quinquilla de 

 la Serra in Montsech. Its small, round aperture with the 

 very strongly developed angular lamella and the strong colu- 

 mellar lamella are very characteristic. 



In size the Montsech form varies relatively little. The 

 figured specimen measures 8.5 mm. long, 3 mm. diameter. 



This local race, which differs a good deal from other forms 

 of bigorru nsis by the constancy of its apertural and size pro- 

 portions, is restricted to the Montsech chain in the Province 

 Lerida, 



The group of Chondrina avenacea (Brag.). 



As will appear in the following exposition, I cannot, from 

 the examination of my Pyrenean and north-Spanish material 

 — several thousand specimens strong — arrange the Chondrinas 

 of the Pyrenean center in a special Group of C. fa/rmesi as 

 Pilsbry has done (XXV, p. 45). What led Pilsbry to this 



