FOOD OF INSECTS. 261 



are extraordinarily increased, or in consequence of some unusual destruc- 

 tion of their appropriate aliment, that they perish for want. The descrip- 

 tion of their food renders unnecessary those artifices to which many of the 

 carnivorous insects are obliged to have recourse ; and none of them, 

 if we except the white ants, whose cunning mode of insinuating themselves 

 into houses in tropical climates has been detailed in a former letter, can 

 be said to use stratagem in obtaining their food. 



Of the carnivorous species, the greater proportion attack their prey by 

 open violence ; such as the predaceous beetles, the Ichneumons, burrow- 

 ing wasps, and true wasps ; the praying insects (^Mantis) ; the bugs (Geo- 

 corisa Latr.) ; dragon flies {LibeJlulina^, &c., which have been before 

 adverted to. But a very considerable number, chiefly, however, of one 

 tribe, that of spiders, provide their sustenance solely by artifice and strata- 

 gem, the singularity of which, and the admirable adaptation of the 

 instruments by which they take their prey to the end in view, afibrd a 

 most wonderful instance of the power and wisdom of the Creator, and 

 have attracted admiration in all ages. A description of these, however, 

 which will require a detailed survey, I must defer to another letter. 



I am, &,c. 



