AMERICAN SPECIES OF VERTIGO. 107 



HENDERSON, Univ. of Colo. Studies iv, p. 172 (South Park, 

 Colo.). SARGENT, Naut. ix, 89 (Clearwater, Minn.). JOHN- 

 SON, Fauna of New England 13, 1915, p. 214 (Maine). 



The light color, tapering form, absence of basal and angular 

 teeth and the small size or sometimes absence of an upper 

 palatal, distinguish this from other American species. Most 

 specimens have the upper palatal fold developed, either dis- 

 tinct though small, or as a trace; yet in some it is wholly 

 absent. The type is no. 58008 A. N. S. P, figured in A. J. C. 

 Figs. 1-3 represent specimens of the type lot. 



The species was placed in the synonymy of V. ovata by Mr. 

 Binney, but Dr. Sterki, in 1888, called attention to its dis- 

 tinctive characters, which are now generally admitted. The 

 two species are not closely related. 



Mr. Wolf found it "abundant in shady copses on green 

 weeds, climbing as high as three feet from the ground. I col- 

 lected 12,000 from standing weeds and not one from the 

 ground, although it was searched well to find them." 



V. perryi differs from V. tridentata by the smaller size, 

 more fragile, distinctly greenish shell, with broader, more 

 rounded aperture, smaller teeth and dark-edged peristome. 



17. VERTIGO MARKI Gulick. PL 13, fig. 17. 



The shell is shortly rimate, ovate, the spire convexly conic, 

 the summit obtuse. Surface nearly smooth; color yellowish 

 (bleached) . The whorls are moderately convex, the last some- 

 what flattened over the lower palatal region, having a low, 

 white crest close to the lip. Aperture with 4 teeth : a strong, 

 moderately long parietal lamella, a low, massive columellar 

 lamella, a small upper and larger lower palatal fold, both 

 tuberculiform. The palatal callus is strongly developed. 

 Peristome is slightly expanded, a little prominent and bent 

 in above the middle of the outer margin. 



Length 2.05, diam. 1.1 mm.; 5 whorls (type). 



Bermuda: Paynter's Vale (G-ulick, S. Brown) and Bailey 

 Bay road cut (Verrill). 



Vertigo marki GULICK, Proc. A. N. S. Phila. 1904, p. 414, 

 pi. 36, f. 7. VERRILL, Trans. Conn. Acad. xii, 1907, p. 170. 



