312 



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. 



Fig. 178.— Mouth 

 pendra morsitans. 



parts of Scolo- 

 After Buffon. 



1. The poison claws or 4th postoral 



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 3rd postoral 



Limb-like appendages. 

 c. Palp-like maxillae. 

 6, Small process formed by 

 their fused bases. 

 Ventral view of head with jaws 

 removed. 



OS. Eye. e. Labrum. 



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 

 glands, 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 Ghilopoda are carnivorous, Lithobius 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 



