ANTERIOR LniBS OF BIRDS, ETC. 95 



Following the true limbs and seated under 

 •what is called the tail, are five pairs of false 

 feet, all, excepting the first pair, bifid at the 

 last joint. These are useless as organs of loco- 

 motion; they are not encased in armour, as 

 are the trae limbs. Such is a brief description 

 of the ordinary arrangement of the limbs in 

 these mail-cl,ad tenants of the waters, but it is 

 totally inapplicable to the lower groups of 

 these crustaceous animals, among which Ave 

 meet with the most strange and singular of 

 beings, as diversified in habits as in structure. 



Passing to the arachnida, we find the sting- 

 armed scorpion, with four jointed limbs on 

 each side of the chest, besides a pair of crab- 

 like claws, which are not limbs, but certain 

 parts of the mouth developed, namely, the 

 maxillae ; these are used for seizing prey. 



In spiders, the limbs are eight in number ; 

 four on each side, and jointed into seven parts. 

 The terminal joint is, in many species, fur- 

 nished with two claws, having comb-like den- 

 tations, and a straight claw besides, with a 

 saw-like edge. It is by means of these claws 

 that the web- weaving spider stretches her lines, 

 shakes her web, and glides along her filmy 

 cordage, by these that she cuts away super- 



