242 HEMITROCHUS. 



having a supraperipheral chestnut zone and numerous bands of a 

 lighter brown both above and below, all bands sometimes lacking. 

 Whorls 4, convex, the first smooth ; sutures impressed ; last whorl 

 rounded at the periphery, deeply descending in front. Aperture 

 transversely oval, oblique; outer lip slightly expanded, slightly 

 thickened within ; baso-columellar lip reflexed, nearly straight, the 

 columella thickened by a strong callus within, which is more or less 

 truncated below. 



Alt. 7 , greater diam. 121, lesser 11 mill. 



Bahamas. 



H. (Plagioptycha') maynardi PILS., Nautilus, Nov., 1891, p. 83 ; 

 Proc. A. N. S. Phila., 1891, p. 456. 



This is one of those species lying somewhat between Plagioptycha 

 and HemitrocJius. It resembles the form described by me as H. 

 brownii in the surface-sculpture, which is decidedly coarse, as 

 in H. albersi. The brown bands of the surface are visible on the 

 face of the thickened and slightly expanded lip, but they are some- 

 times absent. 



H. XANTHOPHAES Pilsbry. PI. 57, figs. 20, 21, 22. 



Shell small, subglobose, solid, narrowly rimate. Spire low-conoid, 

 the apex obtuse. Surface shining, having irregular growth-lines 

 more conspicuous just below the suture. Streaked with reddish- 

 chestnut on a pale isabelline ground, having an inconspicuous paler 

 line at the periphery and a dark band just above it, the latter some- 

 times obsolete. Whorls 4, separated by slightly impressed sutures, 

 the last whorl very obtusely subangular at the periphery, slightly 

 descending in front. 



Aperture half-round, oblique ; peristome not in the least reflected, 

 thickened and pinkish within, showing the band when present. 

 Columella steeply sloping, straight, forming an obtuse angle with the 

 basal margin ; its upper two-thirds flatly reflexed to form a triangular 

 plate nearly concealing the umbilicus. 



Alt. 61, greater diam. 8, lesser 7i mill. 



Alt. 10, greater diam. 11 mill. 



Inagua, Bahamas. 



Helix (Hemitrochus) xanthophaes PILSBRY, Nautilus, Nov. 1891, 

 p. 83; Proc. A. N. S. Phila. 1891, p. 456. 



This is the smallest species yet known of the Hemitrochus group 

 of Helices. It has the same general coloring as the var. of H. vari- 



