218 ATOPOCOCHLIS. 



Genus ATOPOCOCHLIS Crosse & Fischer, 1888. 



Atropocochlis C. & F., Journ. de Conchyl., 1888, p. 11, 

 type Buccinum exaratum Mtill. Euiaxis ANCEY, Bull. Soc. 

 Malac. France, v, 1888, p. 67, footnote no. 5, type B. exaratus 

 Miill. 



Shell Bulimiform, imperforate, thin, diaphanous, roughly 

 striate; suture crenulate; last whorl subangulate; columella 

 vertical, straight and entire, not truncate at base; peristonie 

 strongly reflexed. 



Type A. exarata (Miill.). Distribution, Island of San 

 Thome, in the Gulf of Guinea. 



The single species composing this group has been variously 

 classified, but its true position was indicated by Furtado in 

 1888, who showed that in soft anatomy it closely resem- 

 bles Perideris Shuttl. Atopocochlis differs from Perideris 

 (=^Pseudotrochus) in the rougher sculpture and the reflexed 

 Up, the latter character being of some importance in view of 

 the total absence of even a tendency to expansion of the lip 

 in Pseudotrochus. It is on this ground alone that the group 

 is here given generic rank, a course in which I follow Kobelt. 



The long free course of the vas deferens suggests the prob- 

 ability that Atopocochlis is ovo-viviparous, like Pseudotro- 

 chus alabaster. 



1. A. EXARATA (Miiller). PI. 9, figs. 1, 2. 



Shell imperforate, long-pyramidal, thin but rather solid, 

 diaphanous, scarcely shining; longitudinally sculptured with 

 suboblique, very rough, rude, unequal stria? ; uniform whitish. 

 Spire long-conic, the apex rather obtuse; suture crenulate, 

 somewhat channelled. Whorls 7, nearly flat, the embryonic 

 l!/2 smooth, the last whorl not descending, longer than the 

 spire, angular-carinate a little below the middle, strongly, 

 subobliquely corrugate-striate ; base somewhat tapering, 

 rounded ; columella vertical, straight. Aperture rather large, 

 subangulate-ovate, glossy and white inside. Peristome simple 

 somewhat thickened, strongly reflexed, buff-bordered, tie 

 margins distant; columellar margin dilated, basal margin 

 thickened, expanded, subangulate outwardly. Length 59, 



