6S SPIDERS: THEIR STRUCTURE AND HABITS. 



of ten families ; — and the 6-eyed, which contains only two families. 

 Of foreign spiders there are two tribes in addition to the above, 

 namely, the 4-eyed and the 2-eyed ; but of the 4-eyed tribe only 

 two individuals, so far as I am aware, are known. One of these, 

 the Tetrablemma mediociilahc7n, was discovered by Mr. Thwaites in 

 Ceylon in 187 r, and a description of it is given in "The Pro- 

 ceedings of the Zoological Society for 1873." It bears no affinity 

 to its fellow-tribesman ; and the four eyes are closely grouped 

 round a circular eminence in the centre of the cephalothorax — an 

 adaptation rendered necessary by the conical shape of the latter. 



The 2-eyed spiders are also very scarce, only a few species 

 being known. 



The 12 British families may be divided, like the Roman 

 gladiators of old, into two classes : — the Retiarii and the 

 Secutores, for six of them ensnai-e their prey by subtlety in webs 

 of various descriptions, and six ptirsue their prey and capture it by 

 swiftness of foot. Suppose we designate them the Rdiary and 

 the Hunti7ig spiders, and see whether we can find any interesting 

 members of either class. 



The " Hunters " weave no snares, but hide under stones or 

 leaves, or in crevices, whence they rush out upon passing insects, 

 sometimes springing upon them from a distance and surprising 

 them. Of these the Lycosa (wolfish) and the Saltims (leaper) are 

 very common examples ; and many of them may be found even 

 in the winter months on sunny days in full activity. 



The Drassidce (seizers), although they weave no snares, con- 

 struct silken cells for places of concealment, and in these they lie 

 snugly ensconced through the winter, generally beneath the loose 

 bark of rails or trees. The most remarkable members of this 

 family are the Water-spiders, or more poetically and more 

 classically the Ar^yroiietm (spinners of silver), from the beautiful 

 silvery cell which they build on sub-aquatic plants, and which 

 they fill with air brought down, a bubble at a time, from the 

 surface, just as a glass jar is filled with gas on the shelf of a 

 pneumatic trough. The Rev. J. G. Wood gives a charming des- 

 cription of these interesting little creatures in " Homes without 

 Hands." They are so commonly met with in aquaria, of which 

 they are among the most popular tenants, as to render any 

 farther description of their proceedings almost superfluous. One 

 of the Wolf-spiders, the Dolojjicdes fimbriatus — the generic name 

 signifying " crafty " — also frequents the water ; not building a 

 sub-aquatic home like the former, but leading a piratical life on 

 the surface, cruising about on a raft of dead leaves and twigs 

 bound together Avith cords of silk. It disembarks and runs along 

 the surface of the water in pursuit of insects, and even descends 

 beneath it, not by diving, like the Argyroneta^ but by crawling 



