FOOD OF INSECTS. 425 



Walckenaer and its congeners not only chase their prey 

 in the same situation, but, venturing to skate upon the 

 surface of the water itself, 



" . . • . bathe unwet their oily forms, and dwell 

 With feet repulsive on the dimpling well." 



The Rev. R. Sheppard has often noticed in the fen 

 ditches of Norfolk a very large spider which actually 

 forms a raft for the purpose of obtaining its prey with 

 more facility. Keeping its station upon a ball of weeds 

 about three inches in diameter, probably held together 

 by slight silken cords, it is wafted along the surface of 

 the water upon this floating island, which it quits the 

 moment it sees a drowning insect — not, as you may con- 

 ceive, for the sake of applying to it the process of the 

 Humane Society, but of hastening its exit by a more 

 speedy engine of destruction. The booty thus seized it 

 devours at leisure upon its raft, under which it retires 

 when alarmed by any danger. 



The last of the tribe of hunters that it is necessary to 

 particularize, are those which, like the tigers amongst 

 the larger animals, seize their victims by leaping upon 

 them. To this division belongs a very pretty small 

 banded species, A. sce?iica, which in summer may be 

 seen running on every wall. 



To Walckenaer's swi?nmers, the last of his grand 

 tribes of spiders, including Aranea aquatica, L. &c, the 

 first line of the above quotation from Dr. Darwin is par- 

 ticularly applicable ; for these actually seize their food by 

 diving under the water, their bodies being kept unwet 

 by a coating of air which constantly surrounds them. 

 —Thus one single race of insects exemplify in miniature 



