105 



spiral, distinctly truncated in a young shell, indistinctly so in an old 

 one, with the edge somewhat dilated, so as to resemble a Spiraxis. 



Mean divergence about 9^ ; length of spire .28 inch ; total length 

 ,35 inch ; breadth .06 inch. 



Helix connectens. Shell hemispherical : white, with a horn 

 colored epidermis : with rather coarse striae of growth : apex very 

 obtuse: spire with regular and very convex outlines: whorls nine, 

 very narrow, moderately convex, with a well impressed suture : last 

 whorl slightly convex beneath, with the umbilical region slightly 

 concave : aperture nearly transverse, rather narrow, lunate ; with a 

 very prominent sharp stout revolving lamella far within in the lower 

 part of the last whorl : labrum thin and sharp : labium in old shells, 

 with a rather thick deposit : columella produced very obliquely ; 

 umbilicus wanting. 



Mean divergence about llO*^; height .08 inch; greatest breadth 

 .1 inch ; least breadth .95 inch. 



Helix alligans. Shell globose conoid : white, with a yellowish 

 brown epidermis : with regular striae of growth, which are very 

 coarse on the spire, and fine on the last whorl : apex very obtuse : 

 spire w^ell elevated, with the outlines very convex above, nearly rec- 

 tilinear below : whorls eight, narrow, rather convex, with a well im- 

 pressed suture ; last whorl scarcely convex beneath, with the umbil- 

 ical region planulate : aperture oblique, rather broad, lunate; with 

 a very prominent sharp stout revolving lamella far within in the lower' 

 part of the last whorl : labrum rather thin, sharp : columella mode- 

 rately dilated, and well rounded : umbilicus wanting. This species 

 resembles H. epistylium and H. epistylioides. It is most easily re- 

 cognized by the plane surface of the umbilical region. 



Divergence of the upper whorls about 140°; mean divergence 

 about 95'^; height 1.05 inch; greatest breadth 1.25 inch; least 

 breadth 1.17 inch. 



Helix amab[li.s. Shell nearly planulate above, very convex be- 

 neath, transversely suborbicular : blackish brown, paler on the apex 

 and lip: surface shining, with very fine unequal striae of growth, and 

 obsolete spiral striee on both sides of the periphery : spire slightly 

 elevated, convex : whorls four and one-half, slightly convex in the 

 upper part, and concave in the lower part, with a lightly impressed 

 suture ; last whorl with the periphery extremely acute : aperture in 



