430 CLASS ARACHNIDES. 
suspend it in the air, to enable it to reascend to the point from 
which it had descended, and to waft it from one place to 
another, by the assistance of the wind. These habits are 
generally common with species of this division. 
Several construct between leaves, under stones, &c., nests 
of silk, in the form of oval sacs, and open at both ends. 
These arachnides retire thitherto repose themselves, to change 
skin, and to shelter themselves from the inclemency of the 
weather. If any danger menaces them, they issue forth im- 
mediately, and run off with great agility. 
Some females form, with the same material, a sort of tent, 
which becomes the cradle of their posterity, and where the 
little ones live for some time in common with the mother. 
Some species resemble ants, in raising their anterior feet 
and causing them to vibrate very rapidly. 
The males sometimes betake themselves to combats very 
singular in their manoeuvres, but which have no fatal issue. 
One subgenus, established by M. Rafinesque, that of 
Tessarops, 
Appears to us very much to approach the following in most of 
its characters and habits, but to differ greatly, if there be no 
error, as to the number of eyes, which should be but four. 
(See the Annales Generates des Sciences Physiques, tom. viii. 
p. 88.) 
Another subgenus, which is equally unknown to us, except 
by its description, is that of 
Palpimanus, 
Published by M. Dufour in the Annales des Sciences 
Physiques (Y. Ixix. 5), and which appears to him to be inter- 
mediate between Eresus and Salticus. The disposition of the 
eyes is pretty nearly the same as in the first of these subgenera. 
The tongue is equally triangular and pointed, and the jaws 
