or 
A. E. Verrili— Catalogue of Marine Mollusca. 45 
fade out and the revolving lines become still more prominent, some 
of them often dividing, but on the canal they again become smaller 
and closer. The two nuclear whorls are very small, chestnut-brown, 
searcely carinated, rounded, with the surface finely reticulated by 
lines running obliquely, in two directions, but close to the suture only 
the transverse lines appear. Outer lip with a wide and rather deep 
rounded sinus, a little below the suture; below this it curves strongly 
forward, and recedes again at the canal, which is rather short, 
narrowed, and a little excurved. Columella smooth, with a sigmoid 
curve, and obliquely narrowed at the canal. Aperture subovate, 
sinuous, rather large but narrow. Shell usually white when fresh, 
sometimes pink or pale yellow, often stained with dark ash-gray, even 
while still living ; the columella is usually more or less deeply tinged 
with brownish red, or orange-brown, but is often white. 
Uncini numerous, small, slender, oblong-linear, very acute, twisted 
close to the tip, scarcely barbed; base yellow, relatively large, thick, 
saddle-shaped, with two large subequal lobes and a smaller one, and 
with a long, pyriform appendage about one-fourth as long as the 
shaft. Length of the uncini, 0166""; of shaft, 0104"; diameter of 
shaft, 0012; breadth of base, 0034. 
Length, of an average specimen, 31"; breadth, 14%"; length of 
aperture, 16°"; breadth, 6™™. 
There is considerable variation in the proportions of the Shells. 
In some specimens the spire is much longer and more slender than 
usual, and the whorls are flatter. In others, the shell is stouter, with 
a shorter and less acute spire. Among the shorter-spired ones I have 
found both sexes, but the females are more generally of this form, 
while the males are usually of the more elongated form. 
One of the most elongated specimens is 30°5"" long; 12 broad. 
One of the stoutest is 26™" long; 13 broad. These are both dry 
shells, and the sex is not known. An ordinary male is 24™™ long; 
10 broad. A female, of the longer form, is 26™" long; 12 broad. | 
The animal, in alcohol, has a rather small head, with small, short, 
obtuse tentacles, slightly swollen at base, but without eyes. The penis 
is unusually small, and very much smaller than in P. Packardii,; its 
diameter is about twice, and its length about three times that of the 
tentacles; it is slender, round, and tapers from near the base to the 
acute tip. The foot is rather large, with strong auricles at the 
anterior corners. No operculum, 
This elegantly sculptured species occurred sparingly, living, in 
