I 
79 
CONUS. 
1 
A. Spire nearly truncate or flat. (Plate XIIL 
Fig. 1.) 
B. Pyriform. (Fig. 2.) 
C. Elongated. (Fig. 3.) 
D. Ventricose, contracted at both ends. 
E. Thin, ventricose. (Fig. 4.) 
Shell univalve, convolute and turbinate. Aper- 
ture effuse, longitudinal, linear, toothless, entire at 
the base. Columella smooth. Base attenuated, 
often marked with oblique rugose stri{3e. The aper~ 
ture is sometimes dilated. The whorls are mostly 
flat, often channelled, rarely crowned. The supe- 
rior beauty of this genus renders it highly interest- 
ing, and the conical form distinguishes it from all 
others, except the Voluta and Trochus, the former 
of which has a plaited, and not a smooth colu- 
mella ; the latter a transverse, and not a longitu- 
dinal aperture ; and the conoidal form is erect, and 
not inverted. 
The shells of this genus are usually covered with 
