354 MOLLUSCA. 
base of the tentacles; branchial plumule short, broad, pyramidal, just 
visible at the right side of the neck. Habits sluggish. 
Common on rocks exposed to the surf, Valparaiso. [J. Pp. c.] 
Figure 459, profile view of the typical shell; 459 a, the animal, 
from beneath. 
A small, elevated form, obtained at Orange Harbour, would seem 
to be identical with this species. We often find specimens where the 
central portion representing the early stages of the shell have this 
elevated, conical form, and then the marginal portion suddenly takes 
a new direction, and finishes off with the usual form, the whole looking 
like a hat with a conical crown and broad brim. Mr. Gray has given 
this as one of the forms of his L. variabils. Mr. Nuttall also brought 
home many specimens, which he distributed under the name of P. 
monticula. The animal, as observed by Mr. Couthouy, gives some 
ground for holding it as a distinct species. His description of the 
animal and shell is as follows. 
Animat. Foot very broadly rounded, varying in colour from 
orange or clear ochreous to nearly white. Head darker coloured, lips 
rosy flesh-colour ; tentacles very long and slender, with the eyes large 
and distinct, at their external base; mantle coloured like the foot, 
at margin, but its inner portion has a bright green tinge; mar- 
ginal cirrhi very numerous and fine, tinged with purple at base, 
yellowish-white elsewhere. Branchial plumule very long, its lamelle 
opposite and full of fine, transverse strie, and not extending quite to 
the base of the plumule, which is attached by a small, naked pedicle. 
SuHett small, solid, conical, sometimes depressed, but generally 
quite elevated ; apex acute, subcentral, and in the most elevated ones 
nearly vertical, but in others shghtly inclined forwards. There are 
about ten or twelve rounded, somewhat nodular ribs, situated at the 
sides and behind, and with only some minute, rather crowded ones in 
front. Lines of growth crowded, rather lax ; colour dirty-olive, darkest 
between ribs, and dotted with whitish. Aperture rounded-ovate ; within 
bluish-white, with the central spatula very dark, greatly varied, but 
commonly composed of longitudinal stripes, or annular spots, &c. 
Margin crenulated by the ribs, the spaces answering to the ribs 
