INSECTS. 229 



a rope-dancer : they render the body steady, and 

 obviate all its vacillations in flight. If one of them 

 be cut off, the insect will immediately fly ill, one 

 side evidently overbalancing the other, till it falls to 

 the ground : if both be cut off, it will fly very 

 awkwardly and unsteadily, exhibiting an evident 

 defect of some necessary part. 



The structure of the/«/of these diminutive crea- 

 tures are truly admirable. Those insects that live 

 altogether in water have their feet long, flat, and 

 somewhat hairy at the edges, well adapted to aid 

 their motions in that element. Such as have occa- 

 sion to burrow into the earth have their legs broad, 

 sharp edged, and serrated. Those that use their 

 feet only in walking have them long, and cylindri- 

 cal ; some of the feet are furnished with sharp 

 hooked claws, and skinny palms, by which, from 

 the pressure of the atmosphere upon them, the in- 

 sects are enabled to walk on glass and other 

 smooth surfaces, even with their backs downwards, 

 as in various species of flies : others have somewhat 

 like spunges that answer the same end : and the 

 spider has each foot armed with a kind of comb, 

 propably for the purpose of separating the six 

 threads that issue from so many orifices of its body, 

 and prevent them from tangling. In the hind legs 

 of insects which have occasionally to pass over 

 spaces by leaping, the thigh is very large and thick, 

 and the shank long and frequently arched. 



From the different formations of these, it is not 

 difficult to recognize the habits and modes of life 

 of insects, even where the specimens exhibited 



Q3 



