STRUCTURE OF CHILOPODA 



57 



the Chilopoda and the other three Orders which have still to be 

 described. 



The Chilopoda have only one pair of appendages to each 

 segment of the body instead of two pairs like the Chilognatha. 



The antennae of the Chilopoda are as a rule very long, arid 

 are always longer than in the Chilognatha which we have just 

 described. They differ from those of the Schizotarsia (the third 

 Order, which will be the next to be described) in having the 

 basal joints nearer together ; in other words, they are differently 

 placed on the head. They differ from those of the Pauropoda 

 (the fifth Order) in being straight and not branched. As a rule 

 the antennae of the Chilopoda taper towards the extremity. 



A B C 



FIG. 35. Mouth parts of Lithobius (Latzel). A, Head of Lithobius seen from the 

 under surface after removal of poison claws : a, second maxilla ; b, c, the two 

 shafts of the first maxilla. B, One of the mandibles. C, The two poison 



claws. 



The mouth parts are more numerous than in the Order we 

 have just described (the Chilognatha). They consist of 



1. An upper lip. This is a transverse plate as just described 



in the case of the Chilognatha, but it is not always 

 fused with the rest of the head. It is also usually 

 composed of three pieces, two lateral and a middle piece. 



2. A pair of jaws or mandibles, which are not of so simple a 



form as those of the Chilognatha, but rather resemble 

 those of some of the Crustacea. 



3 and 4. Two pairs of appendages called maxillae resem- 

 bling feet, but used to aid the act of eating instead 

 of locomotion. They are very different in different 

 Chilopods, but are mostly slender and weak and usually 

 provided with feelers (or palps) growing out of the 

 main stem. 



