GASTEROPODS 383 
which cross the whorls, projecting almost one fourth of an inch from the 
body of the shell. Between each of these varices isa large node. There 
is, besides all this, a system of pronounced revolving ribs which cross 
the varices and nodes, giving to the shell a greatly roughened appear- 
ance. The interior is bluish-white. The operculum is corneous, with a 
subterminal nucleus. Unfortunately, thisreally handsome shell is usually 
inerusted with coralline or calcareous matter, which must be removed 
with acid before a good idea of its appearance can be had. In color itis 
reddish-brown to dark chestnut on the varices. It is very common on 
the west coast of Florida, but rarer elsewhere. (Plate LX XII.) 
M.pomum. A more abundant species, found all along the coast 
from Hatteras to Texas. It is not so elongated as the last, and its seulp- 
tural design is much less exaggerated. Between each of the varices are 
two nodules. The aperture is oblong-ovate, and the anterior canal is 
nearly closed and recurved toward the back. Revolving ribs cross the 
varices and nodules. The color is ashen, with chestnut tips upon the 
nodes and varices, and chestnut-colored patches about the aperture. The 
varices are simple and not foliaceous as in M. rufus ; the shell is more 
globose. Length two to three inches. (Plate LXXII.) 
M. (Phyllonotus) fulvescens. The largest of the American murices. 
It is not commonly found except in Texas. 
Genus Trophon 
T. clathratus. A fairly common shell of the Maine coast; 
although it belongs to a deeper zone than that of the tides, it is 
occasionally found after storms upon the shore. It is a small 
fusiform shell, with many prominent longitudinal ribs and a 
produced anterior canal. Trophon is a boreal genus, which finds pg, 5h0n 
the best conditions for life in the icy waters of Labrador and cian. 
Greenland. : ratus. 
Genus Urosalpinx 
The genus Urosalpina is closely allied to Murex and Trophon. 
Several of its species are found on the east coast of the United 
States. 
U. cinerea. This well-known species is regarded by 
Chésapeake and Long Island Sound oystermen much in the 
light of a plague. These active predaceous mollusks live 
upon bivalves, and preferably upon oysters. They bore a 
small round hole through the shell of their helpless victims, 
and then proceed to extract the succulent, fleshy animal 
from within. The oystermen call them by the suggestive 
name of “ drill,” and wage incessant warfare upon them. 
In some years these mollusks appear to go into partnership 
with the large starfish, Asterias, and the combination of the 
two can soon destroy any oyster-bed. The original home of 
ee this destructive little creature is presumed to be in Chesa- 
