MIRIAPODA. 
347 
FAMILY 1. 
CHILOGNATHA*. 
The body generally crustaceous and frequently cylindrical ; the 
antennfe somewhat thicker near the end or nearly equal, and com- 
jjosed of seven joints ; two thick mandibles without palpi, very dis- 
tinctly divided into two portions by a median articulation with imbri- 
cated teeth, implanted in a cavity of its superior extremity ; a species 
of lij: — ligulaf — situated immediately aboAm, that covers them, is 
crustaceous, plane, and divided on its exterior surface by longitudinal 
sutures and emarginations, into four principal areae, tuberculated on 
the superior margin, the two intermediate of Avhich, narrower and 
shorter, are placed at the superior extremity of another arese, serving 
as a common base : the feet very short, and always terminated by a 
single hook ; four feet, situated immediately under the preceding 
part, of the form of the following ones, but more closely approxi- 
mated at base, Avith the radical joint proportionably longer ; most of 
the other attached in double pairs to a single annulus. The male or- 
gans of generation are situated immediately after the seventh pair of 
feet, and those of the female behind the second. The stigmata are 
placed alternately, outside of the origin of each pair of feet, and are 
A’’ery small. 
The Chilognatha move very sloAvly, or slide along, as it AV'ere, and 
roll themselves spirally or into a ball. The first segment of the body, 
and in some the following one, is the largest, and has the form of a 
corselet or little shield. It is only at the fourth in some, and at the 
fifth or sixth in others, that the duplication of the feet commences ; 
the first tAA'o or four feet are eA^en entirely free to their origin, Avhere 
they merely adhere to their respectiA'e segments by a median or 
sternal line. The last tAVO or three rings are Avithout feet. A series 
of pores is obseiwed on each side of the body, Avhich Avere considered 
as stigmata, but, according to Savi, they are simply designed to 
afford a passage to an acid fluid of an extremely disagreeable odour, 
Avhich appears to serve as a means of defence ; the respiratory aper- 
tures, for Avhose discovery aa'c are indebted to him, are situated on 
*■ CiiiLOGNATA, Lat. or the genus Iulus, Lin. 
t The lower lip composed of the two pairs of jaws of the Crustacea, according 
to Savigny. 
