90 AMERICAN SPECIES OF VERTIGO. 



the capacious external excavation over botli palatal plicae. 

 Vertigo morsci is similar to V. berry i in having a long spire 

 relative to the aperture, but the Eastern species is much larger, 

 has more convex lateral outlines, a much more developed point 

 on the outer lip and a stronger crest behind the lip. 



It was reported as Vertigo ovata (Say) var., in Nautilus 

 xxx, p. 38. 



6. VERTIGO BINNEYANA Sterki. PL 11, fig. 12. 



The shell is cylindric-oblong, auburn, somewhat transparent, 

 glossy, weakly, irregularly striate. The whorls are moderately 

 convex, the last having a low but distinct crest behind the 

 lip, a small impression between the crest and the point of the 

 lip, and a rather large impression behind the crest, over the 

 palatal folds. The aperture is rather small. The teeth are 

 whitish ; parietal lamella strong but rather short ; a quite 

 short angular lamella stands even with its outer end. 

 Colmnellar lamella strong, but not long, ascending a little in- 

 wardly. The palatal folds are both quite strong, the lower 

 entering much further. Basal fold short. The peristorne is 

 somewhat expanded, the outer lip a little bent inward above 

 the middle. There is a moderate palatal callus. Length 

 2.1, diam. 1.1, length of aperture 0.75 mm. ; 5 whorls. 



Montana: Helena, type loc., H. Hemphill; Grlendive, Dr. 

 Sterki; drift debris of Musselshell River, Winnecook, S. S. 

 Berry. Manitoba: Winnipeg, Sterki. Nanaimo, Vancouver 

 Island, G. W. Taylor. ( ? New Mexico : Albuquerque, Dr. 

 Sterki.) 



Vertigo bin-ncijatia STERKI, Proc. A. N. S. Phila, 1890, p. 

 33; Nautilus iii, 1890, p. 125 (Helena and Glendive, Mont,; 

 Winnipeg, Man., Albuquerque, N. M.) ; iv, p. 39, pi. 1, f. 1. 

 -BINNEY, Fourth Suppl., Bull. M. C. Zool. xxii, 1892, p. 

 198, fig. PILSBRY, Proc. A. N. S. Phila. 1899, p. 315, fig. 2 

 (specimen from Winnepeg) .-- RANDOLPH, Naut. ix, 102 

 (Seattle, Wash.). SQUYER, Naut. viii, 63 (Mingusville, 

 Mont.). BERRY, Naut, xxix, 125 (Winneeook, Mont.). 



It is smaller and more cylindric than any form of V. ovata, 

 has a longer lower palatal fold, and a less impressed point in 



