AMERICAN SPECIES OF VERTIGO. 97 



Length 1.8, diam. 1 mm. 



Maine : Rockland, Thomaston and Warren, Knox Co., N. W. 

 Lermond. Massachusetts, E. W. Roper. New York: Staten 

 Island, E. W. Hubbard; Westchester Co., E. G. Vanatta; 

 Dutchess Co., W. S. Teator; Madison Co., Henderson, Pilsbry; 

 Herkimer Co., A. Bailey. New Jersey: Burlington Co., B. 

 Long. Pennsylvania, Philadelphia Co., Montgomery Co., 

 Pilsbry; Chester Co., W. D. Hartman. D. C., Sterki. Vir- 

 ginia: Alexandria, Sterki. Ohio: Columbus, H. Moores; 

 Lake Superior, J. T. Crans. 



Vertigo callosa STERKI, Proc. A. N. S. Phila. 1890, p. 31 

 (Columbus, 0., Mass., N. Y.) not of Reuss, 1849. Pupa 

 (Nearctula) supcrioris PILSBRY, Nautilus xii, 1899, p. 103 

 (Lake Superior). Vertigo pygmcca Drap., STERKI, Nautilus 

 vi, May, 1892, p. 5 ; Nachrbl. d. m. Ges. 1889, p. 114. PILSBRY, 

 Proc. A. N. S. Phila. 1900, p. 608. HANHAM, Nautilus xi, 111 

 (Quebec). HENDERSON, Naut. xx, p. 97 (Cazenovia, N. Y.). 

 -JOHNSON, Fauna of New England no. 13, 1915, p. 216 (Me. 

 and Mass. ) . 



This species was first recognized in America by Dr. Sterki ; 

 it had long been in collections, confused with other species. 

 It proves to be somewhat widely spread, having been found in 

 many places between Quebec, Maine, Virginia and Ohio. The 

 strong, continuous crest behind the well expanded lip and the 

 absence of a distinctly defined upper arc or sinulus of the 

 outer lip are its more prominent features. V. gouldii is a 

 paler, much more sharply striate shell with weaker crest and 

 distinct sinulus. V. ventricosa has a weaker and interrupted 

 crest. 



In some lots, as that from Cazenovia, Madison Co., N. Y., 

 the basal fold is small or rarely absent, only five teeth 

 present. In others of the same lot there are both basal and 

 suprapalatal folds, the latter weak; these having seven teeth. 

 Dr. Sterki notes that sometimes the basal fold is bifid, as an 

 individual variation, and occasionally a small angular lamella 

 is present. The crest and the palatal callus vary in strength. 



For other references to V. pygmcea see under Palaearctic 

 species, no. 52. 



