310 HAAS: ABIDA AND CHONDR1NA. 



that I am impelled to award it specific rank. We will see in 

 C. arigonis and C. gorbeana two further cases of local races 

 of C. avenacea, which within their special areas have devel- 

 oped into constant species. 



Chondrin a arigonis (Kossm.). 



Manual, XXV, p. 34, pi. 2, figs. 10-12, 17-18. 



In this species we see a form of C. avenacea jumillensis 

 which has become constant in its differential characters, fully 

 illustrating what was said above of C. aragonica. I could in- 

 vestigate Rossmaessler's series, consisting of about 20 speci- 

 mens, varying only in size and thickness. Comparing with 

 the original series of jumillensis Rossm. (jumillensis guira- 

 onis Pils.), one cannot escape the conclusion that the two are 

 quite identical except as to the apertures. The aperture is 

 formed entirely as in aragonica so far as the peristome is con- 

 cerned, the dentition differing by having two columellar teeth 

 developed. 



Chondrin a gorbeana Pilsbry. 



Manual XXV, p. 56, pi. 3, fig. 12. 



This species too, I view as a form of the avenacea-complex 

 which has become constant, and in this case, C. avenacea 

 kobelti was evidently the parent form. The characters of 

 peristome are entirely similar to those of aragonica and ari- 

 gonis. The peristome is thickened within; on the columellar 

 side somewhat expanded, but not on the palatal side. Tooth 

 reduction has gone further than in the two preceding species, 

 there being present only 1 angular and 1 parietal lamella as 

 well as 1 columellar. 



Pilsbry conceives that this species may be a degenerate form 

 of the bigorriensis group, which in view of its other qualities 

 I do not believe; on the contrary, everything favors my view 

 that it belongs with avenacea kobelti. 



There are before me 21 Chondrinas from Orduiia, collected 

 by Kobelt, thus from near the type-locality, and which both 

 Kobelt and Boettger had in their collections under the name 

 Pupa farinesi var. biplicata. They are identical with gor- 



