CHILONOPSIS. 177 



16. Var. obliteratus Woll. Covered rimate; whorls more ob- 

 soletely biangulate below the suture ; peristome less thick- 

 ened, the right margin nearly simple, scarcely thickened 

 within. Parietal callous far within, in the middle slightly 

 swollen. 



Ic. Var. darvinianus Forbes (pi. 52, figs. 50, 51). Narrower, 

 smaller and more fusiform than C. nonpareil, less rough- 

 ened, with the suture more oblique. Parietal tubercle 

 developed. Umbilicus closed. Found in company with 

 C. nonpareil, imbedded in the ridge-like slopes of in- 

 durated soil in the vicinity of Flagstaff, Sugaiioaf and 

 the Barn. 



The original figure of Chilonopsis sulcata indicates at least 

 a peculiarly senile stage of development, and if it is accurate, 

 perhaps even a distinct species or subspecies of the group. 

 The description follows: 



Chilonopsis. Shell turrite, with 6 convex spirals; umbili- 

 cate; aperture long, narrow, of unequal width, columella 

 strongly dilated, sinuate below and inwardly, margined out- 

 wardly, base forming a canal with the swollen, outwardly 

 triplicate right lip. 



C. sulcata (pi. 62, fig. 25, 27). Turrited, seven- whorled, 

 the whorls convex, longitudinally sulcate. Alt. 6 millim. ; 

 diani. of the first whorl 30 millim. Hab. in St. Jago, South 

 America. 



2. C. MELANIOIDES ( Wollaston ) . PL 52, fig. 53. 



Shell long and rather narrow, turrite-conic ; narrowly, 

 nearly covered perforate; black-brown, sometimes reddish, 

 marked with irregular, usually confluent ochraceous streaks; 

 very closely longitudinally costulate-striate, subopaque. 

 "Whorls 8 to 9, a little convex, separated by a very deep, 

 somewhat wavy suture, obliquely, strongly and rather dis- 

 tantly plicate below the suture, the last whorl obtusely angu- 

 lar at the periphery, less strongly striate below. Aperture 

 narrowly ovate; outer lip simple and thin. Columella obli- 

 quely truncate below, and bearing an oblique fold above; 

 parietal callous a very thin film. 



