CARNIVOROUS ARACHNIDA AND MYRIAPODA 131 



is able to run on the surface of the water in pursuit of prey, or 

 even to dive, this being rendered possible by the entanglement 

 of air -bubbles among the numerous hairs with which the body 

 is covered. Another member of the same family, the Raft-Spider 

 {Dolomedes Jimbriatus), possesses the same powers as the pre- 



Fig. 400. — Hunting Spiders {Salticus scenicus) 



feding, but by constructing for itself a raft of leaves is able to 

 make a more extended use of them. There are other families 

 •of spiders the members of which are thorough-going aquatic forms, 

 a familiar British example being the Water-Spider {Argyroneta 

 aquaticd), of which more will be said in another connection. 



The last group to be here mentioned is that of the Jumping 

 Spiders (fig. 400), which patiently stalk their prey and ultimately 

 secure it by a final rapid jump. A very common little British 

 form, the Harlequin Spider (Salticus scenicus), in which even the 

 larger female is only about a quarter of an inch long, is distin- 

 guished by conspicuous striped markings. 



FALSE SPIDERS (Sqlpugid^) (see vol. i, p. 388) 



These arachnids are rapacious forms superficially resembling 

 large spiders, and have a wide distribution through the warmer 

 parts of both New and Old Worlds, ranging in the latter into the 

 Mediterranean countries of Europe and the south-east of Russia. 

 At first sight they seem to have ten pairs of legs, but the first pair 

 of these apparent legs are in reality the appendages corresponding 

 to the great claws of the Scorpions, serving in this case as feelers, 

 a, function which is also shared by the first pair of legs proper, 

 somewhat as in Whip-Scorpions. The jaws are of large size, and 

 the food chiefly consists of insects, though they also attack other 

 arachnids, even Scorpions. Desert regions are especially affected 

 by them. 



