VERTIGO. 



443 



Fig. 704. 



r. ovata. 



comb ; one on the middle of the transverse lip, a still larger one at 

 right angles on the middle of the pil- 

 lar lip, a minute one at the front of 

 the pillar, and two farther within the 

 shell, one opposite the tooth on the 

 transverse lip, the other on the in- 

 dentation of the outer lip ; umbilicus 

 small, distinct. Length, three for- 

 tieths of an inch ; breadth, one twen- 

 ty-fifth of an inch. 



Inhabits damp, rich places near 

 water, or in fertile fields under bits 

 of l)oard, chips, sticks, &c. It was first noticed in this region by 

 Mr. T. J. Whittemore, at Cambridge. From Maine to Texas. Also 

 quoted from Mexico and Cuba. 



It is a very small, but interesting shell ; double the size, how- 

 ever, of V. mi/iui)i, and of a much more conical shape. Their color 

 is similar. In their armature the two are very diiferent. The pil- 

 lar lip is somewhat broad and flattened. 



Mr. Say describes only four teeth, but the small one at the base 

 of the pillar probably escaped his observation, as it would only be 

 seen under a high magnifier. One of the teeth on the right lip is 

 often wanting. I have occasionally noticed a specimen with two, 

 and even three, teeth upon the transverse lip. 



Vertigo ventricosa. 



Shell ovcate-conic, smooth; whorls four; aperture semi-circular, with five 

 teeth ; umbilicated. 



Isthmia ventricosa, Morse, Ann. N. Y. Lye. viii. 1, fig-s. 1 -.3 (Nov. 18G.5). 

 Vcrtkjo ventricosa, Morse, Am. Nat. i. 669, figs. 61, 62 (1868). 



Shell umbilicate, ovate-conic, smooth, pol- 

 ished ; apex obtuse ; suture deep ; whorls 

 four, convex ; aperture semi-circular, with 

 five teeth, one prominent on the parietal 

 margin, two smaller on the columcllar mar- 

 gin, and two prominent Avithin, contract- 

 ing the aperture at the 1ki.sc ; ])cristoine 

 widely reflected, the right margin flexu- 

 ose, within thickened and colored. Length, seven hundredths of 

 an inch ; breadth, forty-five hundredths of an inch, (ilforse). 



V. ventricosa. 



