XVi PSEUDOSCORPIONS 431 
in this country, twenty British species have been recorded, and 
the known European species number about seventy. 
As might be expected from their small size and retiring 
habits, little is known of their mode of life. They are 
carnivorous, feeding apparently upon any young insects which 
are too feeble to withstand their attacks. The writer has on 
two or three occasions observed them preying upon Homopterous 
larvae. As a rule they are sober-coloured, their livery con- 
sisting of various shades of yellow and brown. Some species 
walk slowly, with their relatively enormous pedipalps extended 
in front and gently waving, but all can run swiftly back- 
wards and sideways, and in some forms the motion is almost 
exclusively retrograde and very rapid. A certain power of 
leaping is said to be practised by some of the more active species. 
The Chernetidea possess spinning organs, opening on the movable 
digit of the chelicera. They do not, however, spin snares like 
the Spiders, nor do they anchor themselves by lines, the sole use 
of the spinning apparatus being, apparently, to form a silken 
retreat at the time of egg-laying or of hibernation. 
External Structure—The Chernetid body consists of a 
cephalothorax, and an abdomen composed of twelve segments. 
The segmentation of the abdomen is emphasised by the presence 
of chitinous plates dorsally and ventrally, but the last two dorsal 
plates and the last four ventral plates are fused, so that ordinarily 
only eleven segments can be counted above and nine below. 
The cephalothorax presents no trace of segmentation in the 
Obisiinae (see p. 437), but in the other groups it is marked 
dorsally with one or two transverse striae. The eyes, when 
present, are either two or four in number, and are placed near 
the lateral borders of the carapace towards its anterior end. 
They are whitish and only very slightly convex, and are never 
situated on prominences. Except in Garypus there is no trace 
of a sternum, the coxae of the legs and pedipalps forming the 
ventral floor of the cephalothorax. 
In the Obisiinae a little triangular projection in front of the 
cephalothorax is regarded by Simon! as an epistome. It is absent 
in the other sub-orders. 
~The abdomen is armed, dorsally and ventrally, with a series of 
chitinous plates with membranous intervals. The dorsal plates 
1 Arachnides de France, vii., 1879, p. 2. 
