AMERICAN SPECIES OF VERTIGO. 101 



crest, and behind that a long, deep, furrow-like impression, 

 over the palatal folds, ascending obliquely from near the base ; 

 no callus within ; lamellae and plicae 6 ; parietal lamella long 

 and curved ; parallel with it is a thin, lamelliform angular ; 

 columellar lamella ascending inwardly. Palatal folds long, 

 the lower pala-tal deep-seated, emerging only about to the inner 

 end of the upper. Basal fold small, subcolumellar in position. 



Length 1.7, diam. 0.95 mm. 



Length 1.6, diam. 0.9 mm. 



Maine : Woodland, Aroostook county, 0. 0. Nylander. 



Vertigo nylanderi STERKI, Nautilus xxii, Feb., 1909, p. 107. 



By the fine striation it has some resemblance to V. gouldti 

 and might be regarded as an extreme form of V. g. paradoxa, 

 as Dr. Sterki has suggested to me. The color is more that 

 of V. bollesiana. It differs from those, and from, all other 

 American species, by the deeper immersion of the long lower 

 palatal fold, and the deep impression in the back, over the 

 palatals. 



It is remarkable that this strongly characterized species has 

 been found in only a single locality. Type no. 1075 Sterki 

 coll. Description and figures from a cotype, 98331 A. N. S. 



12. VERTIGO BOLLESIANA (Morse). PI. 7, figs. 9, 10. 



Shell minutely perforate, cylindrical ovate, delicately 

 striated, subtranslucent ; apex obtuse ; suture well denned ; 

 whorls four, sub-convex ; aperture suborbicular, somewhat flat- 

 tened 011 its outer edge; with five teeth, one prominent and 

 rather curved on the parietal margin, two similar in form, the 

 lower one the smaller, on the columellar margin, and two 

 slightly elevated lamelliform teeth within and at the base, 

 peristome subreflected and thickened. 



Length .065 inch; breadth .035 inch (Morse). 



Maine: throughout the State, type loc. Orono. Massachu- 

 setts, New Hampshire, New York. Also reported from 

 Indiana and Michigan, south to Norfolk, Virginia (Morse) 

 and mountains of East Tennessee. 



Isthmia bollesiana MORSE, Ann. Lye. of Nat. Hist, of N. Y., 

 viii, 1865, p. 209, figs. 4-6. W. G. BINNEY, Terr. Moll. vol. v, 



