BARLEEIA. 393 
area, crosially and vertically cloven, containing the usual 
masticatory processes of the Littorinide ; neck dark, but not 
so much so as the rostrum, quite plain and without appen- 
dages. Tentacula very short, strong, broad, not in the least 
setaceous, with perfectly rounded, somewhat spatulate extre- 
mities ; they are not vibrated on the march; colour very pale 
yellowish-white, with a line of sulphur-coloured beads or 
minute flakes running centrally from base to point; eyes 
very large, black, fixed on bright sulphur inflations at the ex- 
ternal bases. Foot an elongated, rather narrow oval, anteally - 
arcuated, labiated, with scarcely perceptible auricular points, 
posteally rounded, emarginate in the centre of its termination ; 
colour, in the middle of the upper part, confused flake-white, 
margined with a belt of pale smoke hue; sole pale yellow, 
with a decided depressed longitudinal line on the centre of 
the posterior half, not constricted under the slight auricles as 
in Rissoa, and not so slender. The operculigerous lobe is 
small, very little alated anteriorly, but expands below into a 
dark, flat, arcuated membrane; no cirrhus is visible, and I 
believe none exists; it carries a strong, red-brown, suboyal, 
testaceous operculum, sharp above, rounded below and at the 
outer edge, and straighter on the columellar side. The struc- 
ture of the fine striz on the upper surface is of subannular 
figure, with a longitudinal furrow about the middle, which 
forms a raised rib on the under part, the whole of that area 
being thick, coarse and irregular, with, at the nucleus (which 
is nearer the base than the centre), a testaceous apophysis, 
more prominent than in Jeffreysia, and stronger and longer ; 
indeed, as much so as in some of the Chemnitzie. 
These animals inhabit the lower littoral levels at Penzance ; 
their locomotion is deliberate, and they evince considerable 
shyness. There are many fasciated varieties and a white one. 
This animal approaches the Littormidan group, and con- 
ducts from Rissoa to Jeffreysia: as the latter and it have analo- 
gous subtestaceous opercula and apophyses, they naturally lead 
to the Pyramidellide. But this species cannot be placed in 
Rissoa on account of the singular operculum (as the like is 
not seen in any species of that genus), and many other animal 
