CHILONOPSIS. 177 



16. Var. obliteratus Woll. Covered rimate; whorls moreob- 

 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, Sugarloaf 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- who rled, 

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

 diam. 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. 



