AMERICAN SPECIES OP VERTIGO. 103 



the palate externally is different, though gouldn varies in that 

 respect. In bollesiana there is generally a small, narrow crest 

 close behind the lip-margin, and a slight impression at the 

 auricle, suggesting a double curve of the outer lip. This is 

 less marked in gouldii. 



"The inferior columellar (basal) is often wanting or 

 vestigial. In some specimens it is bifid. Some specimens 

 have a very small angular. The peristome was described as 

 subreflected and thickened, but it is narrowly everted, and 

 thus only apparently thickened in a front view." 



13. VERTIGO HEBARDI Vanatta. PI. 8, fig. 4. 



The shell is minute, distinctly perforate, very shortly rim- 

 ate, shortly oval, fragile, corneous; first whorl smooth, the 

 penult irregularly, finely striate, last whorl with few strise; 

 glossy. The whorls are rather strongly convex, the last not 

 noticeably flattened or grooved, and without a crest behind the 

 lip. The aperture is indistinctly triangular and has 5 teeth : 

 angular lamella very low, half as long as the rather short, 

 high parietal. The columellar lamella enters deeply and 

 horizontally, its crest slanting downward. The palatal folds 

 are rather short, subequal, the lower being slightly stouter and 

 a trifle further in. The outer lip is scarcely expanded, some- 

 what straightened, without a projecting point. Length 1.25, 

 diarn. 0.84 mm. ; 4 whorls. 



Florida : Long Key, Morgan Hebard. 



Vertigo hebardi VANATTA, Proc. A. N. S. Phila. 1912, p. 

 445, fig. 



It is most like V. bollesiana, but the shell is shorter, has a 

 distinct angular lamella and no external crest or impression 

 behind the lip. Figure and description from the type. 



14. VERTIGO PERRYI Sterki. PL 7, fig. 7. 



' ' Shell minute, dextrorse, ovate with the apex rather acute, 

 rimate; thin, transparent, of rather dark brown color with a 

 slight greenish tinge [dark olive buff]. Whorls 4^2, rather 

 rapidly increasing, separated by a moderately deep suture, the 

 last comparatively large, occupying over one-half of altitude, 



