432 ARACH NIDA—-CHERNETIDEA CHAP. 
are eleven in number (except in Chiridium, which has only ten), 
and are frequently bisected by a median dorsal membranous line. 
There are nine ventral plates. There is a membranous interval 
down each side between the dorsal 
and ventral series of plates. 
The chitinous membrane between 
the plates is very extensible, render- 
ing measurements of the body in 
these animals of little value. In 
a female full of eggs the dorsal plates 
may be separated by a considerable 
interval, while after egg-laying they 
may actually overlap. The four 
stigmata are not. situated on the 
plates, but ventro-laterally, at the 
level of the hinder borders of the 
first and second abdominal plates. 
The first ventral abdominal plate 
bears the genital orifice. In the 
Fic. 222.—A, Ohernes sp., diagram- same plate there are two other orifices, 
Pa oe eee an anterior and a posterior, which 
ative opening ; p, pedipalp; 1, belong to the “abdominal glands.” 
2, 3, 4, legs. (ihe stigmata ar They were taken by some authors 
at the postero-lateral margins of : 
the Ist and 2nd abdominal sege- for the spinning organs, but their 
ep ine with claws function is probably to supply 
material for the capsule by which 
the eggs are suspended from the body of the mother (see p. 434). 
The Chernetidea possess chelicerae, pedipalpi, and four pairs 
of ambulatory legs, all articulated to 
the cephalothorax. 
The chelicerae are two-jointed, the 
upper portion of the first joint being 
produced forward into a claw, curving 
downward. The second joint is articu- 
lated beneath the first, and curves 
upward to a point, the appendage being ye, 223.—Chelicera of Garypus. 
thus chelate. This second joint, or 4 Flagellum; g, galea; s, 
ye : i serrula. (After Simon. ) 
movable digit, bears, near its extremity, 
the opening of the spinning organ, and is furnished, at all events 
in the Garypinae and Cheliferinae (see p. 437), with a pectinate 
