PURPURA. MONOCEROS. CONCHOLEPAS. 105 
P. NucLEus. Small, ovate, shining, smooth, 
but transversely striated near the lip and at the 
base; brownish chestnut; aperture rounded; lip 
striated within. 4. W. 23. 91. 
MONOCEROS. 
Shell oval; aperture longitudinal, terminating in- 
Seriorly by an oblique sinus; a conic tooth at 
the base of the lip internally. 
M. cinguLatum. Ovate-oblong, contabu- 
lated, whitish, covered with a reddish epidermis, 
and adorned with smooth black belts and fine 
transverse striz ; whorls angulated above; aper- 
ture very white. 12. W. 24. 168. 
M.IMBRICATUM. Ovate-ventricose, roughish, 
ash-colour or reddish grey, with very crowded 
transverse imbricated scaly ribs ; whorls rounded; 
spire short ; lip crenulated. 2. W. 22. 54. 
M. cRASSILABRUM. Ovate, thick, smooth, 
reddish ash-colour; whorls convex; spire rather 
exserted ; lip exceedingly thick, almost double, 
toothed within; horn short, obtuse. 1}. E. 
396. 2. 
CONCHOLEPAS. 
Oval, inflated, semi-spiral; summit inclined obliquely 
towards the left margin; aperture ample, lon- 
gitudinal, oblique, with a slight notch at the 
F 2 
