PUPILLA. 



83 



astomosing net-like sculpture and pale grayish color. Sub- 

 sequent whorls are moderately convex, and the last one rises 

 somewhat and becomes flattened laterally towards the aperture. 

 The aperture is about as wide as long, somewhat squarish with 

 rounded angles. The peristome is expanded, the outer and 

 basal margins thickened with a cinnamon callus within, upper 

 external margin thin ; columellar margin dilated. There is a 

 transverse white nodule on the parietal wall within the angle 

 of the lip, united with the latter, and continued in a thin 

 callus across to the columellar lip-insertion. Length, 4 mm.; 

 diam., 1.9 mm. ; 6% whorls. 



Guadalupe Island, Lower California, at Northeast Anchor- 

 age at an elevation not greater than 100 ft., in the canyon 

 back of the buildings, abundant (G. D. Hanna). 



Pupilla goniodon Pils., Proc. Cal. Acad. Sci. (4), XVI, 

 1927, p. 172, pi. 7, fig. 3. 



The presence of a strong angular nodule and the more deli- 

 cate riblets differentiate this species from P. sterkiana. In ex- 

 ceptional specimens there is the barely perceptible trace of a 

 parietal tooth, rather deep within ; in none do I see any colu- 

 mellar tooth or truncation, such as P. sterkiana usually shows 

 in an oblique view in the aperture. The species was collected 

 alive in some numbers. 



Pupilla guadalupensis Pilsbry. PL 15, figs. 10, 11. 



Shell cylindroid, slowly tapering in the upper half, cinna- 

 mon colored, only slightly glossy, very evenly sculptured with 

 retractive riblets paler than the ground color, from a half to a 

 third as wide as their intervals and about 14 to 16 in one milli- 

 meter on the face of the last and penult whorls; the usually 

 paler 1% embryonic whorls have the net-pitted sculpture of 

 Striopupilla. Subsequent whorls are rather strongly convex. 

 Aperture rounded below, straightened with rounded angles 

 above; no trace of a crest or contraction behind outer lip. 

 Peristome expanded, heavily thickened within except at the 

 posterior-lateral curve, continuous in a slightly free or adnate 

 callus across the parietal wall. Aperture typically four- 



