Symphyla, Chilopoda . 
125 
These minute Myriopods have a wide distribution ; they have Table-case 
been found in Europe, India, Java, Sumatra, South Africa and • No ‘ 
America. A few species occur in this country. There is a single 
family, S colop endrellidae, with two genera, Scolopendrella and 
Scutigerella. 
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 11 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 ways 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 
orifices at the posterior extremity of the body, a character in which 
they agree with 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 about thirty-nine to over one hundred and forty. Each 
