CHAPTER XXVIII 

 Centipedes and Millipedes 



Class Myriapoda: (Gr. ;ui//)ios = numberless; 7roy? = foot). 



This Class includes inter alia the Centipedes, whose great 

 poison-claws, which can inflict a very painful wound, entitle 

 them to some consideration here. 



In the Myriapoda the body as a rule is elongate and is 

 composed of a head and of numerous segments which, with 

 their appendages, are all nearly alike. The legs are composed 

 of several segments and usually end in a single claw. 



The general plan of the head is very similar to that of an 

 insect, the appendages being a pair of many-segmented 

 antennae, a pair of mandibles, and two pairs — though in many 

 cases only one pair — of maxillae. 



Breathing is performed by tracheae like those of insects, 

 which have definite openings, usually on the sides of the body. 



The Myriapoda are grouped in four orders, as follows : — 



1. Chilopoda, or Centipedes. There are two pairs of 

 maxillae. The first pair of legs are much enlarged " poison- 

 claws." The genital pore is on the penultimate segment of 

 the body. 



2. Diplopoda, or Millipedes. There is only one pair of 

 maxillae. Most of the body-segments have two pairs of 

 appendages. The genital ducts open on the 2nd or 3rd 

 body-segment. 



3. Pauropoda (Traupo? = few ; 7roy? = foot). Minute Myria- 

 pods with nine pairs of legs and triflagellate antennae. They 

 resemble tiny Centipedes in form ; but, like Millipedes, have 

 the genital openings close behind the head, and only one pair 

 of maxillae. 



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