ty 
ZOOLOGY 
face, and terminating in a claw. The fifteenth pair are often 
directed backwards. The anus is terminal, and the genital 
pore in both sexes is just in front of it, on the ventral surface. 
Fie. 178.—Mouth parts of Scolo- 
pendra morsitans. After Buffon, 
1. The poison claws or 4th postoral 
appendages, 
s. Median cutting processes 
formed by the anterior edge of 
the basilar sterna. 
2. One of the mandibles with its 
cutting edge to the left. 
3. The maxillae and 8rd _postoral 
appendages, 
a, Limb-like appendages. 
c, Palp-like maxillae. 
6. Small process formed by 
their fused bases. 
4, Ventral view of head with jaws 
removed. 
@. Hye. e. Labrum. 
i The alimentary canal runs straight through the body with- 
out any loops. It consists of a short stomodaeum, which 
receives near the mouth the secretion of a pair of salivary 
elands, of a wide mesenteron, and of a rectum, which opens by 
the terminal anus. Two long white tubes—the Malpighian 
tubules—open into the posterior end of the mesenteron ; they 
are longer than the body, and are consequently somewhat 
coiled. The Malpighian tubules secrete uric acids and urates, 
and thus function as organs for the excretion of nitrogenous 
waste matter. 
The Chilopoda are carnivorous, Zithobius living upon flies, 
insect larvae, and earthworms, which are quickly killed by the 
poison from the poison claws; these also assist by holding the 
prey whilst the jaws tear it in pieces. 
The alimentary canal occupies a considerable portion of the 
body-cavity ; this space is to some extent occluded by the “ fat- 
body ” which in Myriapods and Insects forms large masses of 
tissue abundantly supplied with tracheae. The body-cavity is 
full of blood, which is kept in circulation by the contractile 
heart. The latter organ stretches all along the dorsal surface, 
lying immediately beneath the integument. It consists of 
fifteen chambers, one in each segment: the first of these, which 
