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ZOOLOGY 



Class Chilopoda 



Centipedes The centipedes are so called because they are supposed 

 to have a hundred legs, though the number differs, in 

 different forms, from thirty to over three hundred. They 

 differ from the diplopods in having only one pair of legs 

 to a segment, and by the greater number of joints to the 

 antennae. . In the diplopods the antennae do not have 

 more than seven joints, in the chilopods they have at 

 least twelve. Some centipedes (Scolopendra), common 

 in the Southern and Western states, are very large ; others 

 (Geophilus) are small and extremely slender. The poison 

 claws represent the first pair of legs, greatly modified. 

 They are connected with glands, and the secretion flows 

 through a passage opening near the tip of the claw. 



In addition to the important classes Chilopoda and 

 Diplopoda, there are two represented by minute and 

 rarely observed species. Both have only one pair of 

 legs to a segment, though in other respects they differ 



The greatly from the chilopods. The Symphyla (Scuti- 



gerella and Scolopendrella) differ from the chilopods in 

 lacking maxillipeds (jaw feet), or modified legs serving 

 as mouth parts. They have twelve pairs of legs, and 

 the antennae are quite long, sometimes with as many as 

 fifty joints. The Pauropoda (Pauropus and Eury- 

 pauropus] are more like diplopods, with short and 

 curiously modified antennae, which are branched at the 

 end. They wholly lack special respiratory organs, 

 whereas the diplopods possess tracheae (air tubes), with 

 openings (spiracles) at the bases of the legs. Symphyla 

 and Pauropoda may be found under stones or stumps 

 in damp places, and are probably more widely spread 

 than the published records show, as owing to their 

 minute size they have been overlooked. 



