100 AMERICAN SPECIES OF VERTIGO. 



inward. Inferior columellar (basal) is usually wanting or 

 quite small" (Sterki). 



Length 1.75, diam. 1 mm. (fig. 6). 



Maine : Woodland, Aroostook Co., type loc., Nylauder. 

 Quebec, Sterki. 



Figured from cotypes, no. 119007 A. N. S. P. It had been 

 mentioned before (Nautilus xiii, 103), with the note "Fine 

 examples with the two palatal folds continuous and one an- 

 gular" terms not diagnostic of the race. It stands midway 

 between gouldii and nylanderi. 



. Vertigo gouldii cristata Sterki, n. subsp. PI. 12, figs. 

 4,5. 



"The shell is rather large, about 2 mm. long (1.8 to 2.1) ; 

 form cylindrical to somewhat oblong, barrel-shaped. Surface 

 striae rather fine. Some distance behind the outer and basal 

 lips there is a rather large, conspicuous crest, which does not 

 extend above the middle ; behind it there is a broad flattening 

 or impression over the palatals, the base being narrow there, 

 then becoming rather broadly rounded towards the aperture. 

 A small angular lamella may be either present or wanting. 

 There is no basal ('lower columellar') fold." (Sterki.) 



Length 2.1, diam. 1,2 mm. (fig. 4). 



Canada : Quebec, rather abundant, A. W. Hanham. 



A strongly marked race, having the crest as well developed 

 as in many examples of V. pygmcca,, but without a callus in 

 the palate, and with the sculpture of gouldii. Figured from 

 cotype no. 119008 A. N. S. P. 



11. VERTIGO NYLANDERI Sterki. PL 7, figs. 13, 14, 15. 



Shell rimate, oblong, with a rather acute apex, cinnamon 

 colored, pellucid ; whorls 4i/ 2 -5, quite convex, with a deep 

 suture ; sculptured with somewhat irregular, crowded strife 

 (except the embryonic whorl) ; the last occupying about one- 

 half of the altitude, gradually narrowed towards the aperture, 

 which is small. Peristome slightly everted, margin not thick- 

 ened. The outer margin has an indentation barely above its 

 middle, forming a well-marked sinulus; behind it a trace of a 



