EXERCISE VIL. 
THE GARDEN SLUG (Limax molestus). 
Sub-kingdom—MouLuLusca, Class—GASTEROPODA. Order—PULMONATA. 
1. External characters—Examine the slug when crawl- 
ing. Notice the small shield-like mantle on the back, 
and below it, on the right side, the pulmonary 
opening ; the long tentacles on each side of the head, 
with the dark eyes at their tips; and the shorter 
pair of tentacles below them. The longer pair are 
often called the eye peduncles. Notice also the long 
flat muscular foot on which the animal crawls. 
2, Kill the animal either by immersion in water between 
100° and 130°, or by putting it in weak vinegar 
and water (the first is the better method, but it takes 
longer time), then put it into strong alcohol for ten 
minutes, to coagulate the mucus; wash it, clean off 
the mucus with blotting paper, and pin it on to the 
cork, foot downward, with a pin through the end of 
the tail. Cover with water. 
3. Internal Structure Make a longitudinal incision from 
the tail to the left of the mantle, and then to the 
centre of the head. Pin out the integument on 
either side, and remove the pin from the end of 
the tail. Notice the following points. At the head, 
the yellowish-white buccal mass, with the purple 
cerebral ganglia, joined by the commissure behind 
it, and the purple tentacles (if retracted) on either . 
