CH. XIV.] THE SPIDER. 231 



monstrous bird-spider tynygale avicularia) of South 

 America ; it is at least two inches long, and reputed 

 (although on authority which has been denied) to 

 hunt for and devour birds. In general outline and 

 shape they all present a strong family likeness. 

 The body is divided into two parts : the fore-part, 

 containing the head and breast, is separated from 

 the hind-part by a ligature, or very slender thread. 

 The fore-part, together with the feet, which are in- 

 serted into the breast, is covered with very strong 

 scales. The hind-part is clothed in a very fine and 

 supple skin, which is covered with hair. In different 

 parts of the head, they have several fine eyes — gene- 

 rally eight, and sometimes no more than six ; two 

 in the fore-part, two in the hind-part, and the rest 

 in the sides. They are all without eyelids, and are 

 covered with a hard, polished, and transparent crust. 

 As these eyes are immoveable, they have been mul- 

 tiplied, to convey to them, on all sides, intimations 

 of whatever it concerns them to know. The fore- 

 part of the head is furnished with two stings, or 

 rather branches, shagged or indented with strong 

 points like a couple of saws, and ending in a nail 

 formed like the claw of a cat. Near the point of 

 the nail is a small aperture through which their 

 poison is ejected. These arms or branches are ex- 

 tremely formidable to their enemies : they open and 

 extend at pleasure. When no longer wanted for 

 use, the nails are each of them bent down upon its 

 branch, like a pruning-knife clasped upon its handle. 

 They are all likewise furnished with eight legs, like 

 those of a crab ; and at the extremity of each are 

 fixed three crooked and moveable claws : that is to 

 say, a small one placed in the side, like a spur, by 

 the assistance of which they fasten themselves to 

 their thread — and two others of a larger size. The 

 internal curve of these is indented, and they enable 

 the insects to fix themselves wherever they please, 

 and to slide either obliquely or downwards, by 

 grasping whatever comes in their way. 



