ODONTOSTOMUS. u-> 



Smaller than 0. pantagruelinus, often more distinctly striated 

 spirally, having the teeth less developed, and with low white bosses 

 strung along the suture.' It sometimes attains a length of 55 mill.; 

 and while usually da^rk colored and less solid than the larger species, 

 it is sometimes quite as pale and equally as strong. This form was 

 recognized as distinct by both Moricand and Jay, prior to *Beck's 

 publication, but the Swiss and American authors used names pre- 

 occupied in the genera to which they referred the species ; hence 

 Beck's name leucotrema, " white-mouth," prevails. 



O. EXESUS (Spix). PI. 8, figs. 79, 80. 



Shell riinate-perforate, fusiform, solid and strong, coarsely plicate 

 above, wrinkled and pitted below, the raised sculpture dirty white, 

 sunken portions fleshy or ashen-gray ; densely and minutely striate 

 spirally. Whorls 8, convex, the last constricted and more or less 

 pitted behind the lip, pinched at the base. Aperture subvertical, 

 oblong, more or less distinctly pink, the intervals between the teeth 

 usually dark ; obstructed by four large teeth : a thin entering parietal 

 lamella, a squarish columellar lamella, and two folds within the outer 

 lip, the lower palatal compressed and entering, the upper palatal 

 squarish and obliquely transverse. Peristome very broadly ex- 

 panded and reflexed, especially at the lower outer portion ; pink, 

 usually with dark shading around the teeth. 



Length 68, diam. 13, length of aperture 17^ mill. 



Length 34, diam. 13J, length of aperture 16J mill. 



Brazil: Province of Bahia (Blanchet). 



Clausilia exesa SPIX, Test. Bras., pi. 14, f. 1 (1827) DESHAYES, 

 An. s. Vert., viii, p. 215 (1838) Pupa exesa WAGNER in Spix, 

 Test. Bras., p. 19 Helix ( Cochlodina) exesa (?) RANG, Ann. des Sci. 

 Nat., xxiv, 1831, p. 62. MORICAND, Mem. Geneve, vii, p. 441; 

 ix, p. 61, pi. 4, f. 8, 9 (var. zonata). Odontostomus exesus BECK, 

 Index Moll., p. 54 Bulimus exesus PFR., Symbols, ii, p. 114; 

 Conchyl. Cab., p. 291, pi. 56, f. 3, 4 ; Monogr., ii, p. 83; iii, 367; 



iv, 435; vi, 75 DESK., Histoire, p. 120, pi. 162, f. 7-10 REEVE, 



Conch. Icon., pi. 38, f. 227 HIDALGO, Journ. de Conchyl., 1870, 

 >. 51. 



The coarsely-shriveled surface, pink lip, more or less stained with 

 >urple-black, which runs out between the teeth, or is confined to 

 their bases, are characteristic. There is a wide range of variation in 



