HOLOSPIRA. 93 



This species resembles II. goldfussi Menke, but is slightly 

 smaller, with a shorter neck to the aperture and a less reflected 

 and triangular peristome. It is entirely destitute of the 

 remarkable internal lamellae which characterize H. goldfussi. 

 It is named in honor of M. H. Crosse, who has monographed 

 the genus. (Dall.) 



In the single specimen I have seen (pi. 23, fig. 75) the rib- 

 lets are subobsolete on the cylindrical portion of the shell. 

 The column is of about equal diameter throughout the cylin- 

 drical portion. H. crossei is most nearly related to H. re- 

 mondii, but differs in the coarser external sculpture, some- 

 what more slender contour, and the convex, not flattened, 

 whorls of the terminal cone. 



18. H. REMONDII (Gabb). PL 23, figs. 61-63, 70; pi. 24, 

 figs 1-4. 



Shell perforate and rimate, cylindric, conic above, thin, 

 pale brown. Whorls 11^-12%, the first 2 smooth, convex, 

 the first whorl wider and more bulging than the second; fol- 

 lowing 4 whorls (pi. 24, fig. 4) gradually widening, the cone 

 flattened, angular, and projecting more or less above the 

 suture, sharply and finely ribbed obliquely, the riblets much 

 narrower than the intervals. Succeeding whorls are convex 

 and obliquely ribbed, but in many specimens the riblets be- 

 come subobsolete on the last 2 or 3 whorls. The last whorl is 

 a little narrower, scarcely projects beyond the level of the 

 ventral outline, and is rounded below, but with the base de- 

 fined by an obtuse angle, and usually perforated by a distinct 

 though small, rounded umbilicus. Aperture circular exter- 

 nally, somewhat ovate inside, the peristome expanded through- 

 out. Internal column (pi. 23, fig. 70) small, smooth, a trifle 

 larger above, and with a weak spiral swelling in the penulti- 

 mate whorl. 



Length 11.3, diam. 3.7 mm. ; whorls 12%. 



Length 9, diam 3.2 mm. ; whorls 11%. 



State of Sonora, Mexico: 1% leagues from Arivechi, 

 Sahuaripa Valley (A. Remond). 



Cylindrella remondii GABB, Amer. Journ. of Conch., i, p. 



