OTINA. 
223 
horny ; operculum none ; shell depressed, nearly 
ear-shaped ; spire small, lateral ; aperture large ; 
peristome nearly continuous ; pillar arched. 
On the sea-coast, just above or just within the 
edge of the tide-line. The animals walk by the 
alternate motion of the two sections of the foot and 
of the lower surface of its large broad head. 
This animal was first described as belonging to 
the genus Helix. Dr. Fleming referred it to Velu~‘ 
tina ; and after examining the animal, I separated it 
as a section of that genus under the name of Otina. 
Mr. Clark adopted it, and placed it, with some doubt, 
among the genera of Auriculidce^ which he considers 
pectinobranchous. Messrs. Forbes and Hanley refer 
it to PyramidelladcB^ describing the animal as having 
^^an armed tongue and jaws, and branchial plume 
single.” But in 1854 I showed that the animal, 
instead of having gills, respired free air in a closed 
branchial cavity, and had teeth like other Pneumo^ 
nobranchiata, and compared it with Auricula. Dr. 
Pfeiffer forms for it a small sub-family of Otinince 
in Auriculidce; but the form of the animal, and 
especially of the tentacle and the shell, bears much 
more affinity to the family Limnceadce. 
100 . 1. Otina otis. — Shell depressed, semi-ovate, 
rather solid, very slightly striated, covered 
with a thin periostracum, rather shining 
brown, often eroded; spire minute; whorls 
2 the last somewhat compressed ; aperture 
nearly horizontal, ovate oblong; peristome 
nearly continuous, with the pillar edge liver- 
coloured. 
