66 



ZOOLOGY 



vessel divided into sacs by valvular partitions, conveying 

 the blood towards the head. .Air is conveyed through 



FIG. 27. CENTIPEDE. 



a, centipede ; b, anterior part of the body seen from above ; c, eyes of the 

 right side magnified ; d, head ; e, antenna ; /, anterior part of scolopendra, 

 .seen from below ; g, perforated hooked jaws ; h, posterior part of the body ; i, 

 the same seen from below ; k, one of the somites with foot and stigma ; lc' I, 

 isolated stigmata ; m, antenna of Geophiius. 



the body by tracheae which communicate with the atmos- 

 phere by stigmata. In those groups which have one pair 

 of limbs attached to each segment, the stigmata occur on 

 the sides of every alternate somite; but when the segments 

 bear two pairs of limbs, each is furnished with a pair of 

 breathing apertures. This seems to corroborate tho 

 opinion, that in these cases, each segment consists of two 

 amalgamated somites. 



80. The nervous system is similar to that found in 



