134 CONTRIBUTIONS 
cles; substance of the shell thin; spire elevated, pointed at 
the apex; whorls nine; mouth two fifths the length of the 
shell. 
Length .6, Breadth .2, of an inch. 
Observations. This species differs from the last described, 
in having a double row of tubercles, and in the mouth 
being rather longer. It has a very close resemblance to 
the P. semicolon (Sowerby) .* 
P. Baumontii.t Plate 4. Fig. 127. 
Description. Shell ovately fusiform, transversely striate, 
furnished with a single row of compressed tubercles near 
the middle of the whorl; substance of the shell rather thin ; 
apex pointed; whorls eight, subcanaliculate above ; mouth 
nearly one half the length of the shell. 
Length .6, Breadth .2, of an inch. 
Observations. A beautiful little species, differing some- 
what in its form from those above described, as well as in 
the tubercles and strie. The tubercles are compressed, and 
adorn the wider portion of the whorl. The strize are wide 
apart, and below the line of tubercles these are, for four 
or five rows, alternately, smaller. In the canal above the 
tubercles, flexuous folds of the form of the sinus are visibly 
and closely set. 
* Min. Conch. plate 146, fig. 6. 
| Named after the distinguished geologist Elie de Baumont. 
