178 CHILONOPSIS. 



Length 9-11, diam. 3.5, aperture 3.5 lines (Woll.). 



Length 16, diam. 6 mm., whorls 7y 2 . 



St. Helena; Northern slopes of the ridge below Diana's 

 Peak, at the roots of grass in damp places ( Wollaston) . 



Subulina melanioides WOLL., Testacea Atlantica p. 550 

 (lS78).Bulimulus m., SMITH, P. Z. S. 1892, p. 267, pi. 22, 

 f. 18. Pachyotus melanioides DALL, Proc. A. N. S. P., 1896, 

 pp. 416, 419. PILSBRY, t. c. p. 418, footnote (teeth and 

 jaw figured). 



In this species the first half whorl appears to be smooth; 

 then spiral striae faintly appear. The second whorl has 

 coarse rib-striae crossed by some spirals. The oblique nodules 

 appear at the beginning of the third whorl. On the later 

 whorls the spirals become weak or obsolete, except the peri- 

 pheral angle. It is a decidedly less evolved species than 

 C. nonpareil, in which the sculptural characters are more 

 accelerated. Dall 's conjecture that the latter arose from some 

 such form as C. melanioides seems well founded. I have fig- 

 ured the jaw and teeth of this species, from a dry specimen. 



3. C. SUBPLICATUS (Sowerby). PI. 52, figs. 55, 56. 



Shell narrowly rimate, long and slender, rather thin; red- 

 dish brown, paler at the suture and base, or bleached to a 

 gray tint, elaborately mottled and striped with opaque white. 

 Outlines of spire convex, the apex obtuse. Whorls 6% to 7, 

 slightly convex. The first 2 whorls are smooth and convex. 

 The following whorls are densely striated longitudinally, the 

 striae somewhat wavy; and at first there are some indistinct 

 spirals. Bounded nolule-like folds below the suture appear 

 weakly on the third whorl, increase in size, becoming largest 

 on the intermediate whorls, and diminish on the last whorl, 

 where they are absent for some distance. The last whorl is 

 oblong and usually shows indistinct traces of a peripheral 

 angle. Aperture fusiform-oval, narrowed towards both ends. 

 The outer lip is simple and obtuse, not thickened; columellar 

 margin dilated, continued above in a thin parietal callous. 

 Columella obliquely truncate at the base, concave in the 

 middle. 



