24 STROPHOCHEILUS-BORUS. 



wrinkled, with slight spiral cords, subregularly squarely malleated ; 

 penultimate whorl flattened on the left side, the last whorl ventricose, 

 widened transversely, subdepressed on the hack, slightly ascending 

 in front. Aperture vertical, acuminate above, subdilated below, 

 five ninths the shell's length, inside whitish-blue ; peristome thick- 

 ened, white, narrowly reflexed, margins joined by a rather thick 

 callus which has a tubercle above; right margin slightly flexuous, 

 colurnellar margin oblique, reflexed, adnate, covering or nearly 

 covering the perforation. 



Length 105, diam. 56 mill. (Hid.'). 



Rio Janeiro (Paz). 



?? Bidimus eantagallanw PFR., Monogr. iv, p. 365 (1859), not of 

 Rang. Bu limits gummatus HIDALGO, Journ. de Conch., Cat. Coq. 

 Amer. Merid. p. 41 (1870) ; Viag. al Pacif. p. 49, pi. 4, f. 1 ; pi. 5, 

 f. 1. 



Three specimens with the locality " Brazil " only, are before me, 

 two of which are figured on plates 19 and 20. It is unquestion- 

 ably a species distinct from B. ovatus v. chionostomus, being dis- 

 tinguished by the more conic spire, closer and narrower folds of 

 early whorls, aperture distinctly wider and more truncate below, the 

 outer lip not vertical but sloping outward ; columella less vertical, 

 being oblique and passing without distinct angle into the parietal 

 wall. It is also less expanded, not suddenly spreading as in ovatus. 

 Moreover, the callous lump of the parietal wall is strongest at the 

 edge of the parietal callus, which is not thinned out as in ovatus. 

 For the rest, there are no very decided differences, although the 

 cuticle in gummatus is of a varnish or gummy brilliancy, the spiral 

 cords are quite obvious, and the malleation is not of the pattern seen 

 in ovatus and is less pronounced. 



S. OVATUS Miiller. PI. 12, figs. 60, 61. 



Shell large, solid, oval; chestnut-brown with numerous darker 

 and lighter streaks ; surface glossy. Nepionic shell of 4 whorls, the 

 first smooth, planorboid, the following radially costate, costee separ- 

 ated, short, and minutely spirally granulate, post-nepionic whorls 1%, 

 at first densely granulated and slightly malleated, the last whorl 

 without granulation, glossy, finely malleated all over. 



Aperture much exceeding half the length of shell, acuminate- 

 ovate, narrow and acute above, narrowly rounded below; peristome 

 pink edged ; outer lip curved at upper insertion, then rather straight, 



