Par 1a, 
TERRESTRIAL. 
Order —PULMONOBRANCHIATA (continued). 
Family I[—LimMacipz (Slugs). 
The bodies of the Limacide are straight, not coiled ; 
the upper part of the back is covered with a fleshy 
shield or mantle, under which the shell, if any, is 
located. This shell is rudimentary, and is usually 
an oblong plate, more or less membranaceous. They 
have four tentacles similar to those of snails, the longer 
or upper pair terminating in bulbs in which the eyes 
are situated. ‘The whole lower surface of the body 
forms the foot. They have a respiratory orifice 
situated on the right side of the body by the edge of 
the mantle. 
Genus I.—ARION. 
All the Arions have a slime gland at the extremity 
of the tail. 
