Symphyla , CJi ilopoda . 1 1^ 5 



These minute Myriopods have a wide distribution ; they have Table-case 

 been found in Europe, India, Java, Sumatra, South Africa and ■'^°- -' • 

 America. A few species occur in this country. Tlaere is a single 

 family, Scoloprndrcllichic, with two f^enera, Scolopcnclrella and 

 Sciitigerella. 



Class 8.— CHILOPODA (Centipedes). 



In the Chilopoda the body consists of a number of similar 

 segments, and with the exception of the last, each of them is pro- 

 vided with a pair of appendages. The generative organs open upon 

 the penultimate segment, behind the legs of the last pair. The 

 anterior extremity is differentiated into a head which bears a 

 single pair of antenniform, many-jointed, pre-oral appendages. The 

 anterior four pairs of post-oral appendages are modified as jaws, the 

 first pair being the bi-segmented biting mandibles, the second pair 

 the biramous foliaceous maxillae, the third pair the leg-like palpi, 

 or " palpognaths," and the fourth pair the powerful biting poison- 

 jaw^ or " toxicognaths." The rest of the appendages are loco- 

 motor in function, and are tipped with a single claw; those of the 

 last pair, however, are sometimes modified in various w\ays in 

 relation to sex or otherwise. 



The Chilopoda were formerly associated with the Diplopoda. 

 They differ, however, essentially from the Diplopoda, as well as from 

 the Pauropoda and Symphyla, in the position of the generative 

 oriiices at the posterior extremity of the body, a character in which 

 they agree wdth the Hexapoda or Insects. They are often swift- 

 moving forms, and are carnivorous. 



There are two sub-classes, Artiostigma and Anartiostigma. 



Sub-class ARTIOSTIGMA. 



The tracheal tubes are retained in the Artiostigma, and 

 their orifices open upon the pleural area of more or fewer of the 

 segments. A dorsal plate (tergum) and a ventral plate (sternum) 

 are present on each of the leg-bearing segments ; and the number 

 of ventral plates never exceeds that of the dorsal plates. There 

 are four orders. 



Order — Geophilomorpha. 



Chilopoda in which the body is long and vermiform, consist- 

 ing of a large number of somites varying, according to the genus, 

 from aboi;t thirty-nine to over one hundred and forty. Each 



