S94 PROCEEDINGS OF THE ACADEMY OF [1899. 



former in the distinct basal tooth, bi-ramose parietal lamina, colora- 

 tion, etc., and from P. matermontana it differs in being more 

 robust with far less open umbilicus and different coloration. P. 

 nelsoni Dall {Nautilus, xi, p. 74), of which I have seen the 

 types, is another species of the same group. 



Praticolella strebeliana n. sp. 



Shell nari'owly umbilicated, rather depressed, thin; uniform, pale 

 corneous, having a dull sheen as if frosted, caused by an exces- 

 sively minnte roughening of the surface. Spire low conic ; whorls 

 4f , the first one glossy, obtuse, the rest slowly widening until the 

 last, which is decidedly wider, moderately deflexed in front, the 

 periphery obtusely angular on the first half, becoming rounded on 

 the latter portion; scarcely any constriction behind the lip, but 

 opaque there. Aperture oblique, wider than high, shortly ellip- 

 tical, moderately excised by the parietal wall; peristome expanded, 

 narrowly reflexed, with a slight rib-like thickening within; mar- 

 gins approaching, the basal regularly arcuate, columellar margin a 

 little dilated at the insertion, slightly impinging on the narrow 

 umbilicus. 



Alt. 7.5, diam. 12 mm.; aperture, oblique alt. 5.7, width 7.2 

 mm., including peristome (type). 



Alt. 6.5, diam. 10.2 mm. (smallest adult specimen). 



Diente, near Monterey, State of Nuevo Leon, Mexico. 



Praticolella ampla (Pfr. ), which is the nearest to this species, 

 differs in being far more globose, with a rounded-lunate aperture 

 and more deeply arcuate basal lip, somewhat as in Eulota similaris, 

 while this species has a transversely elliptical, smaller aperture, 

 with far less arcuate basal lip, and much more depressed body-whorl. 

 P. berlandieriana and griveo/a are not closely allied to the present 

 species. 



Pratieolella strebeliana is named in honor of Hermann 

 Strebel, one of the aljlest investigators of the Mexican mollus- 

 can fauna. 



Numerous fresh specimens were collected, but only one Avas found 

 living. 

 Thysanophora proxima n- sp. 



Similar to T. conspureatella (Morel.), but with more elevated 

 spire, narrower umbilicus and far wider spaced oblique cuticular 



