254 THE CHICAGO ACADEMY OF SCIENCES. 



Animal: (Fig. 79.) With a short, stout foot, which is 

 divided into two portions, the anterior with the head and ten- 

 tacles, and the posterior with the balance of the body; anterior 

 portion bilobed and projecting, when the animaj is in motion, 

 in front of the head proper; body colorless; tentacles about a 

 third the length of the foot, cylindrical, obtuse, with the eyes 

 placed near the base of the tentacles, on the back. Genitalia? 

 Jaw arched, with no ribs or denticulations. Radula with rows 

 of teeth in a slightly bent series; the central tooth is narrow, 

 equilateral and unicuspid, the laterals broad, short, and den- 

 ticulated. Animal terrestrial. 



Fig. 79. 



CARYCHIUM EXIGUUM Say. (Binney, Fig. 9.) Animal showing head 

 and lower surface of foot. 



Distribution: United States, Europe and Africa. 



KEY TO SPECIES OF CARYCHIUM. 



a. Shell cylindrical, aperture over one-third of total length, 



whorls four and one-half exiguum 



b. Shell elongated, aperture one-third of the total length, 



whorls five and one-half exile 



102. Carychium exiguum Say, pi. xxvi, Fig. 4. 



Pupa exigua SAY, Journ. Phil. Acad., Vol. II, p. 375, 1822. 

 Carychium existelium BOURGUIGNAT, Mag. de Zool., p. 220, 1857. 

 Carychium euphceum BOURGUIGNAT, 1. c., p. 221, 1857. 

 Carychium exiguum mexicanum PILSBRY, Proc. Phil. Acad., p. 319, 

 pi. xiv, Figs. 7, 8, 9, 1891. (Variety.) 



Shell: Cylindrical, pupiform, translucent, spire long and 

 conic; color pearly white, surface shining, somewhat pol- 

 ished, lines of growth numerous, crowded, minute; whorls four 

 and one-half, regularly increasing, convex, somewhat oblique 

 in position; spire very long, conic, less than two-thirds the 

 length of the entire shell; apex obtuse; sutures very deeply 

 impressed, making quite a perceptible v-shaped depression 

 between the whorls; base of shell rounded, exhibiting a round 

 and deep umbilicus; aperture ovate, rounded below, narrowed 

 at the upper part, more than one-third the total length; parietal 

 wall with a large plait midway between the terminations of the 

 peristome; there is a somewhat prominent callosity on the base 



