ORTHALICUS. 209 



in tint on the latter lialf, and girdled by a broad blackish band at the 

 periphery, with traces of one or two fainter dusky bands above ; hav- 

 ing some oblique variceal dark streaks. Surface glossy, with close, 

 irregular wrinkles of growth, roughened at the varices. Whorls 6 

 (in a decollate and plugged specimen, figs. 2, 3 ; but G^ according to 

 Fulton), the apical 2^ thimble-pitted, those of the spire hardly con- 

 vex, the last oblong, convex ; apex obtuse. 



Aperture oblique, ovate, pure white within, but with a very wide 

 black internal border shading through violet into the white ; peri- 

 stome obtuse, thick, a trifle expanded, black ; columella vertical, bi- 

 sinuate, the upper fold or nodule much stronger, purple tinted, the 

 lower one slighter; parietal callus black. 



Alt. 59, diam. 29, longest axis of aperture 29 mill. 



Alt. G7, diam. 31 mill. (type). 



Bogota, Colombia. 



Porphyrobaphe approximata FULTON, Ann. and Mag. N. H. (6), 

 xviii, p. 103 (July, 1896); xx, pi. 6, f. 6, (1897). 



Allied to 0. atramentarius, adamsoni and pounsiamis. From the 

 last of these it differs in coloring, the more oblique aperture, and the 

 straight lateral outlines of the spire. 0. adamsoni is much larger, with 

 more ample body-whorl, and has spiral stria? ; it agrees in the color- 

 ing of the aperture. O. atramentarius is much' more closely related 

 to approximates , differing from it chiefly in the different color-pattern 

 of the exterior, the browner black of the lip and parietal wall, and 

 the red-purple rather than violet or blue-purple internal shading of 

 the lip-border, and the tinted instead of pure white color of the 

 interior. The form of the columella is closely approached by some 

 specimens of atramentarius. 



Fig. 1 represents the type ; 2 and 3 are from a specimen received 

 from the author. 



O. ATKAMENTARIUS (Pfeiffer). PI. 38 ; pi. 39, fig. 7. 



Shell ovate-conic or oblong-conic, thick and solid ; two or three 

 early whorls flesh-tinted, the succeeding whorls of the spire fleshy or 

 white, with irregular, broad ragged stripes and narrower oblique 

 streaks of purple-brown, the last whorl (1) whitish-lilac or pale 

 brownish with similar stripes, streaks and spots, or an indefinitely 

 mottled pattern, or (2) wholly or on the last half of a uniform black- 

 ish-purple color ; sometimes showing an obscure band at the per- 

 14 



