90 AMERICAN SPECIES OF VERTIGO. 



the capacious external excavation over both palatal plicae. 

 Vertigo morsel 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. 

 Columellar 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 peristome 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; Glendive, 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 Unneyana 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 (Winnecook, 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 



