VERTIGO. 215 



Vertigo Bollesiana, MOUSE. 



Shell minutely perforate, cylindrical-ovate, delicately striated, subtranslucent ; 

 apex obtuse ; suture well defined ; whorls 4, subconvex ; aperture suborbicular, 

 somewhat flattened on its outer edge ; with 5 

 teeth, one prominent and rather curved on the pari- Fi S- 120> 



etal 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.) 



Isthmia Bollesiana, MORSE, Ann. N. Y. Lye., VIII. 

 209, Figs. 4-6 (Nov. 1865). 



Vertigo Bollesiana, MOUSE, Amer. Nat, I. 669, Figs. 63- 64 (1868). W. G. 

 BINNEY, L. & Fr.-W. Sh., I. 250 (1869). GOULD and BINNEY, Inv., 442, 

 Fig. 703 (1870). TRYON, Am. Journ. Conch., III. Ft. 4, p. 308, PL XV. Fig. 

 25 (1868). 



New England ; New York ; Virginia. Distribution, therefore, like the last 

 species. 



Animal unobserved. 



Jaw of the same width throughout, slightly rounded at the ends; cutting 

 edge without projections, finely striated. 



Lingual membrane with 88 rows of (12 1 12) teeth; base of attachment 

 notched at outer posterior corners ; square, widening posteriorly, armed with 

 three minute denticles, central one largest ; laterals having two minute den- 

 ticles apart, outer denticle nearly obsolete ; marginals scarcely notched. 



A comparison of this description and figure 

 Fig - 12L of dentition with that of Lehmann (PI. XIV. 



a* c= " e=s 



^ (P, na c= ^ Fig. 53) will prove that this species cannot be 



identical with P. pygmna of Europe, as has 



Lingual membrane of Vertigo Bollesi- . T _ 



ana (Morse). bcen su gg estc <l ty Mr. Gwyn Jeffreys (Ann. 



Mag. Nat. Hist., 1872, 246). 



Vertigo milium, GOULD. 

 Vol. III. PI. LXXI. Fig. 1. 



Shell very minute, subcylindrical, diminishing equally to both extremities ; 

 epidermis dark-amber, or chestnut-color ; whorls 5, rounded, very minutely 

 striated, decreasing slightly to the apex, which is obtuse ; suture deep ; peri- 

 stome white, slightly reflected ; aperture lateral, half the width of the last 

 whorl, within brownish, general shape semicircular, truncated abruptly and 

 directly by the last whorl, a testaceous deposit upon which forms the transverse 

 margin, and connects the two extremities of the peristome ; circumference made 

 up of two curves of different radius uniting in the peristome, where the June- 



