118 LECTURE IX. 



nute animals on which Spiders prey. The legs 

 are eight in number, and at the end of the body 

 are four or five small teats or organs through 

 which the animal draws its thread. Each of these 

 teats is pierced with a vast number of holes through 

 each of which proceeds a distinct thread, and the 

 animal can either draw its thread from all the 

 holes at once or by any particular number; in 

 short what we call a single spider's thread may 

 consist, according to some computists, pf not less 

 than six thousand distinct filaments. The size to 

 which the European spiders arrive is not very 

 great, but the hotter regions of Africa and Ame- 

 rica produce spiders of a size so gigantic as to be 

 formidable even to birds and many other animals 

 on which they prey. One of the chief of these is 

 the Aranea Avicularia or Bird-catching Spider, of 

 which very capital specimens may be seen in the 

 JLeverian Museum. These Spiders are found 

 principally in the hotter parts of South- America. 



The genus called Acarus or Mite contains the 

 smallest of all known Insects, as well as some of 

 considerable size. The mites are a very numerous 

 race. The generic character consists in having 

 eight legs, and in many species a kind of claspers, 



