POISONOUS INSECTS AND THEIR RELATIVES 411 



1911. COOLEY, R. A. Tick control in relation to the Rocky 

 Mountain spotted fever. Bull. 85, Montana Expt. Stat. 



1911. HUNTER, W. D., and BISHOPP, F. C. The Rocky Mountain 

 spotted-fever tick. Bull. 105, Bu. Ent, U. S. Dept. Agri. 



1902. OSBORN, H. Poisonous insects. Reference Handbook of 



the Medical Sciences, Vol. V, pp. 158-169. 

 1909. WARBURTON, CECIL. Arachnida. Cambridge Natural 



History, Vol. IV, p. 424. 

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CENTIPEDES 



The centipedes belong to a group of animals more 

 closely related to the insects than are the spiders. Earlier 

 authors place the centipedes and millipedes together in 

 the class Myriapoda (many-footed). More recent in- 

 vestigators tend to separate the two groups and rank 

 each as a distinct class. So far as the writer is aware, 

 the millipedes are harmless to human beings, and we have 

 no concern with them. The centipedes, on the other 

 hand, are reputed to be poisonous to man, especially the 

 larger, tropical forms. The centipedes which we shall 

 discuss and which are commonly known and dreaded, 

 belong, for the most part, to the family Scolopendridce. 

 We shall refer to them as scolopendras or simply as 

 centipedes. 



The scolopendras have long bodies flattened above and 

 below and divided into 21 to 23 ring-like segments. Each 

 segment bears one pair of legs and the last pair is rather 

 long. The head bears a pair of long antennae (Fig. 141). 

 They are active, swift-moving creatures and live, for the 



