NATURA.L THEOLOGY. 293 



VI. In many species of insects the eye is fixed, 

 and consequently without the power of turning 



ing particulars concerning them, since they have been divided into 

 vagrants, hunters, swimmers, and water-spiders, sedentary, and 

 mason-spiders ; thus evincing a variety in their condition, activity, 

 and mode of hfe ; and we cannot be surprised to find them varying 

 intlie performance of their vital functions (as, for example, in their 

 mode of breathing,) as well as in their extremities and instruments. 

 Of these instruments the most striking is the apparatus for spinning 

 and weaving, by which they not only fabricate webs to entangle 

 theh' prey, but form cells for thefr residence and concealment ; 

 sometimes living in the ground, sometimes under water, yet breath- 

 ing the atmosphere. Corresponding with their very singular or- 

 ganization are their instincts. We are familiar wnth the watch- 

 fulness and voracity of some spiders, when their prey is indicated 

 by the vibration of the cords of their net-work. Others have the 

 eye and disposition of the lynx or tiger, and after crouching in con- 

 cealment, leap upon their victims. Some conceal themselves 



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