HELIX. 223 



shell, blackish, or bluish black, darkest on the head, neck, 

 and tentacles. Tentacles short in proportion to the length 

 of the animal, and set widely apart. Respiratory foramen 

 in the angle formed by the junction of the lip with the 

 body-whorl. Base of foot whitish, the locomotive band 

 defined by two very fine lines, or furrows. A double, 

 marginal furrow runs along the sides of the foot, from 

 the head nearly to the posterior extremity, where it 

 passes upward, and joins that from the opposite side, 

 leaving posteriorly a flattened, rounded extremity, some- 

 what prominent and glandular. Upon the centre of the 

 extremity is a longitudinal fissure, or sinus, which is 

 sometimes expanded, and at other times closed and invisi- 

 ble. Secretion of mucus from the extremity profuse. 



SHELL thin, depressed on the upper surface ; epider- 

 mis dark, approaching to chestnut-color, shining and 

 smooth, wrinkled ; whorls four and a half, with irregular, 

 oblique wrinkles, the last whorl very voluminous, and 

 expanding transversely towards the aperture ; suture 

 very little impressed ; aperture ample, sub-circular, 

 within pearly or iridescent ; lip simple, thin, brittle, with 

 a light, testaceous deposit within, the two terminations 

 approaching each other very nearly ; umbilicus deep, not 

 much expanded. 



Greatest transverse diameter more than an inch. 



GEOGRAPHICAL DISTRIBUTION. Has been found in 

 nearly all the Southern, Middle, Western, and Northern 



States. 



