TARENTDLA. LEAPING SPIDERS. 219 



the Tarentula, so named from the city of Tarentum, in Italy, 

 in the neighbourhood of which it is common, is very celebrated 

 on account of its reputed venomous powers. Like all the 

 Spiders, it has a poison-gland in its mandibles ; but the idea that 

 its wounds are followed by death, or by a complaint termed 

 Tarantism, which can only be cured by the aid of music and 

 dancing, has originated in the imagination only. Some species 

 of the genus Dolomedes live upon the tops of trees, upon the 

 leaves of which they make a funnel-shaped silken nest ; whilst 

 others inhabit plants in the neighbourhood of water, on which 

 they find their prey, running upon its surface with surprising 

 quickness, and even entering it without being wetted. The 

 Spiders of the tribe of SALTATORES, or Leapers, have, as might 

 be anticipated from their name, the legs fitted rather for leaping 

 than for running. One of these is very common in summer upon 

 walls and windows exposed to the sun ; and its habits may be 

 watched with much interest. It moves in short leaps, and stops 

 suddenly at intervals, raising itself upon its legs, as if to survey 

 the neighbourhood. When it discovers a fly, or especially a 

 gnat, it approaches it cautiously until within leaping distance ; 

 when it darts upon it, not fearing to take even a perpendicular 

 leap, because it always at the same time suspends itself by a 

 thread, which it winds off as it advances. This thread also 

 serves to suspend it in the air, and enables it to mount up again 

 to the spot from which it leaped, or to sustain it whilst the wind 

 carries it from place to place. Many species of this group 

 construct, amongst leaves, under stones, &c., silken nests, in the 

 form of oval sacs, open at each end ; into which they retire in 

 order to take rest, to moult, and to take refuge against the 

 inclemency of the weather. If menaced with danger, they 

 quit these retreats, and run off very rapidly. Some species 

 construct, with the same material, a kind of tent, which serves 

 as the birthplace of their posterity, and in which the young 

 reside for some time with their parent. 



756. The family VAGANTES, or Wandering Spiders^ consists 

 of the single tribe LATERIGRADA ; the name of which (meaning 

 Side- Walkers) expresses the curious power which they possess, 



