8 MOLLUSES FEOM WEST COAST OF AMERICA— BALL. vol.xviii. 



nacre shines througli tlie outer coating of the shell quite conspicuously 

 when it is wet. Height, 20; maximum diameter, 18; height of aper- 

 ture, 7 mm. 



West Mexico, in deep water; also at U. S. Fish Commission station 

 3387, and in the gulfs of Panama and California, in about 100 fathoms. 



T,n)e.—l^o. 122957, U. S. :N^. M. 



This elegant species has an operculum with a great many very nar- 

 row whorls nnd entire margin. The animal is brilliantly painted with 

 scarlet and black, and has well developed eyes and an unusually long 

 muzzle. 



CALLIOSTOMA TURBINUM, new species. 



Shell small, margarit.'^-form, with six and a half rounded whorls; 

 nucleus minute, white, smooth, of one whorl, followed by strongly sculp- 

 tured, rather inflated whorls separated by an inconspicuous suture; 

 sculpture on the spire of rather elevated, narrow, spiral ridges, of which 

 the most posterior is always beaded, though the beading on the others 

 fails on tbe apical whorls; in front of this ridge is a smaller one, then 

 three, or on the last whorl five, subequal, larger ones, the third form- 

 ing the periphery of the whorl, the suture being laid against the most 

 anterior ridge; the base has al)Out twelve, subequal, more crowded, 

 spiral threads, faintly or not at all beaded, larger toward the axis; the 

 body of the shell is of a nacreous waxen tint, with transverse flammules 

 of dark brown, which articulate the spirals, are much fsiinter on the inter- 

 spaces, but do not reach the base, on which the spirals are more or less 

 articulated with reddish- brown; the base is somewhat flattened, the 

 jDcriphery not keeled, the pillar short, white, with a minute umbilical 

 chink; aperture subquadrate, nacreous, sulcate by the external sculp- 

 ture; there is no projection at the distal end of the pillar. Height, 12; 

 major diameter, 12.5 mm. 



U. S. Fish Commission stations 2902 and 2972, among the Santa Bar- 

 bara Islands, in about 100 fathoms. 



Type.— Bo. 122578, U. S. N. M. 



This is a pretty species, with a polished outer coat, through which 

 the luicre shines very distinctly. 



Genus AN APLOCAMUS, Dall. 



Shell short-spired, with a thick brown periostracum, with a simple, 

 sharp, outer lip, parietal callus, arched pillar, the anterior extreme of 

 the aperture slightly produced and pointed, as in some Litorinas; the 

 base imperforate, the ai)ertare destitute of lir;ie, teeth, or other i)rojec- 

 tions; operculum, relatively to the size of the animal, large; area of 

 attachment, small; form, U-shaped, the apex without any spiral incli- 

 nation, rather blunt, the increment being applied to the proximal end, 

 and the edges entire. 



Type. — A. borealis, Dall. 



