216 TERRESTRIAL AIR-BREATHING MOLLUSKS. 



tion causes an angle projecting inwards, the smaller curve comprising about 

 one fourth part, and forming the superior portion of the peristome ; teeth 6, 

 two on the transverse margin, sharp, projecting, and tooth-like; one in the 

 angle between the columellar and transverse margins, broad, massive, and prom- 

 inent, with occasionally one or more tubercles about its base ; one on the 

 lower part of the columellar margin ; two on the peristome, in the base of the 

 aperture, and at the junction of the two curves ; umbilicus rather wide. Length, 

 •| mill. ; diameter, | mill. 



Jhipa milium, Gould, Bost. Journ. Nat. Hist., III. 402, PI. Til. Fig. 23 (1840) ; 

 IV. 359 (1843); Invertebrata, 187, Fig. 118 (1841). — DeKay, N. Y. Moll., 

 48, PI. IV. Fig. 44 (1843). — Adams, Vermont Mollusca, 157 (1842). — Pkeif- 

 FER, Mon. Hel. Viv., II. 362. — Binney, Terr. Moll., II. 337, PI. LXXI. Fig. 

 1. — KtJSTER, in Chemnitz, ed. 2, 119, PI. XV. Fig. 39-42. 

 Vertigo milium, W. G. Binney, Terr. Moll., IV. 148. — Mokse, Amer. Nat., I. 



669, Figs. 65, 66 (1868). 

 From New England to Texas. A species of the Eastern Province. 

 Animal very light gray, darkest above ; foot thick, broadest behind the mid- 

 dle, tapering suddenly to a point. Eye-peduncles somewhat globular at tips, 

 in the centre of which are the eye-spots ; no tentacles. 



The most minute of our species, but though the eye cannot, without the aid 

 of the microscope, detect its characters, they are very strongly defined. The 

 parts about the aperture are particularly well-developed, the teeth being long, 

 compressed, and sharp, and the transverse margin distinctly bounded. Pro- 

 fessor Adams mentions that twelve mature specimens weighed less than a six- 

 teenth of a grain. It is found under or among dead leaves. It is gregarious 

 in its habits ; when one is found, many others may be quite certainly found 

 near it. 



Vertigo ovata, Say. 

 Vol. III. PI. LXXI. Fig. 4. 



Shell minute, ovate-conic, ventricose, dark amber-colored; whorls 5, very 

 convex, the last much inflated, diminishing rather rapidly to a somewhat acute 

 apex, with an indentation towards the aperture ; suture rather deep ; peristome 

 thin, somewhat expanded, with a groove behind and a thickening within ; aper- 

 ture in general outline semicircular, the curve consisting of segments of two 

 different-sized, but well-defined circles, the smaller on the right at the junction 

 of the peristome and body-whorl, comprising about one fourth of the whole con- 

 tour, and forming an angle at their junction ; teeth generally 6, two on the 

 transverse margin, two on the columellar margin, the upper of which is mas- 

 sive, the lower pointed, and two on the peristome, in the base and at the junc- 

 tion of the two curves, sharp and prominent ; umbilicus expanded. Length, 3 

 mill.; diameter, \h mill.; aperture, 1 mill. long. 



Vertigo ovata. Say, Journ. Acad. Nat. Sci. Philad., II. 375 (1822) ; ed. Binney, 

 26. —Binney, Terr. MoU., II. 334, PI. LXXI. Fig. 4. — W. G. Binney, Terr. 



