158 



NATURAL HISTORY OF VERMONT. 



Part I. 



FRESH WATER AND LAND SHELLS. 



tifully at Crown Point under stones in 

 very dry situations. A few dead speci- 

 mens have been found in Bridport, on the 

 margin of hike Cliainplain, wliich may 

 have been drifted from the opposite side. 



Piqia alhilahris. — Ward. Inedit. 



Description. — Shell brown, finely stri- 

 ate, long-ovate, tapering above the penult 

 whorl ; whorls six, convex, with a well 

 impressed suture ; aperture a little less 

 than half as long as the spire, without 

 teeth, with a reflected, white, thick, flat- 

 tened margin ; umbilicus moderate. — 

 Length 0.18 inch; breadth 0.07 inch. 



Remarks. — This species is well known 

 as Say's cijdostoma viarginata. As the 

 latter specific name is preoccupied in the 

 genus Pupa, to which it belongs, it has 

 received tlie name under which we have 

 described it. A very few specimens only 

 have been found alive at Crown Point, 

 and one dead on the Vermont shore of the 

 lake. 



Pupa contracta. — Sav. 



Description. — Shell white, ovate, ta- 

 pering above the body whorl ; whorls five, 

 convex, with a well impressed suture; 

 aperture sub-triangular, with the trans- 

 verse lamina raised, and forming with the 

 labrum a continuous lip, much contracted 

 in the throat, with lliree teeth, one on the 

 transverse lip, large, prominent, and sin- 

 uous, another on the right side, where the 

 throat is most contracted, and the third is 

 merely a convexitj^ caused by the fold of a 

 large umbilicus. Length 0.1 inch ; breadth 

 COG inch. 



Remarks. — This species is easily rec- 

 ognized by its elevated transverse lip. It 

 is found under wood or stones in moist 

 pastures. 



Pupa Tappaniaiia. — Ward. Inedit. 



Description. — Shell very small, pale 

 horn color, translucent, tapering above 

 the penultimate whorl ; whorls a little 

 more than five, convex, with a well im- 

 pressed suture ; aperture sub-orbicular, 

 (the penult whorl cutting off" about one- 

 third of the circle,) about one-third of the 

 length of the sliell ; margin sharp, with a 

 narrow contraction in llie sub-margin, 

 beneath wliich is a tiiickening within, on 

 which are the labial teeth ; teeth eight, 

 five primary and three secondary ; of the 

 former the largest is on the penultimate 

 whorl, the next largest on the left side of 

 the aperture ; at the base, beginning at 

 the left hand, is a primary', then a secon- 

 dary, a primary, a secondary, a primary, 

 and another secondary, extending nearly 

 .to the upper extremity of tlie right mar- 

 gin : the last three primaries are not con- 



stant in size ; umbilicus open. Length 

 0,08 inch ; breadth 0,05 inch. 



Remarks. — This species is easily dis- 

 tinguished from the preceding by its 

 teeth. 



Pupa exigua. — Say. 



Description. — Shell white, shining, 

 elongate, tapering above the penultimate 

 whorl ; whorls six, convex, with a well 

 impressed suture ; aperture ovate, with 

 the upper lip oblique, margin reflected 

 and thickened, teeth two, of which the 

 larger is on the oblique lip, and the other, 

 wliich is small, is on the leftside ; umbil- 

 icus distinct. Length 0,08 inch; breadth 

 0,03 inch. 



Remarks. — This shell is easily distin- 

 guished by its neat, shining appearance, 

 and graceful form. It is more common 

 tiian anj' other species of this genus in 

 Vermont, and is found under stones and 

 logs in moist places. 



Genus Helix. 

 Generic CkrnYifkrs.-SUeW orbicular or globose, 

 usually conve.\ or conoid above, but sometimes 

 fialtcned ; ajierture wider than long, srmi-eiliptic 

 or lunate, contiguous to the a.\is of the shell, with 

 the outline interrupted by the intrusion of the pe- 

 nult whorl. No operculum. Tlie animal, com- 

 monly called a snail, has four tentacles, of which 

 the posterior pair are larger and oculiferous. 



Helix alholahris. — Say. 



Description. -Shell globose-conic, with 

 a light brown, sometimes reddish epider- 

 mis, with five parallel oblique incremen- 

 tal strife, and very minute revolving lines; 

 whorls five and a half, convex, with a 

 well impressed suture ; aperture contract- 

 ed by the labrum, which is white, flat, 

 broadly reflected, and extends beneath to 

 the centre of the shell, covering the um- 

 bilicus, which is open only in the young. 

 Greatest breadth 1.35 inch ; least breadth 

 1 inch ; height 0.8 inch ; divergence of 

 the spire 135°. 



Remarks. — This species is found very 

 commonly in most parts of Vermont. 

 On tlie islands called the Four Brothers, 



