CHAPTER X. 

 OF THE CLASS OF MYRIAPODA. 



804. THE Class Myriapoda, which is very closely allied to 

 the Insects, appears to lead from those highly organized articu- 

 lated animals towards the lower division of the Annelida. The 

 legs are to a certain extent intermediate in conformation be- 

 tween the more highly-organized legs of Insects, and the simple 

 bristle-like appendages possessed by some of the Annelida ; and 

 on looking at the form of their bodies, we see that they are dis- 

 tinguished by a uniformity in the character of their segments, 

 nearly as great as that which prevails in the Annelida ; so that 

 an lulus (Fig. 539) might almost be likened to an Earthworm, 

 provided with a stiifer integument and with slender legs : 

 whilst, on the other hand, the adaptation of the respiratory 

 organs to breathe air with regularity and energy, the complexity 

 of the masticating apparatus, the possession of distinct eyes, and 

 many other characters, indicate their affinity with Insects ; in 

 which class, indeed, some Naturalists comprehend them. They 

 differ from insects, however, not merely in the absence of wings, 

 but in the great multiplication of the segments, which are nearly 

 always twenty-four at the least, each provided with a pair of 

 legs ; and also in the absence of any line of division between the 

 thorax and abdomen. As we shall see hereafter, there are cer- 

 tain Crustacea which bear a considerable resemblance to them in 

 regard to the equality of the segments, and general organisation ; 

 but these are characterized by their branchial respiration, and 

 the number of their segments is usually much inferior. 



805. The covering of the body of these animals is firm, and 

 of a somewhat horny character, resembling that of many Insects. 

 The division into segments is very distinct ; a flexible membrane 



