EPHEMERAE. 251 



the water beetles, are ever eaten by trout, I 

 know not, but it is most probable. These 

 singular animals are most commonly found 

 in stagnant waters; fitted for flying, swim- 

 ming, diving, and walking, they are omni- 

 vorous, and usually fly from pool to pool in 

 the evening. They deposit their eggs in the 

 water, where their larvae live, but which, 

 to undergo transmutation into the beetle, 

 migrate to the land. But there is hardly 

 any insect that flies, including the wasp, the 

 hornet, the bee, and the butterfly, that does 

 not become at some time the prey of fishes. 

 I have not, however, the knowledge, or if I 

 had, have not the time, to go through the 

 lists of these interesting little animals ; but of 

 the family of one of them I must speak the 

 ichneumons, that deposit their eggs in cater- 

 pillars, or the larvae of other flies, and which 

 feed on the unfortunate animal in which they 

 are hatched, and come out of its interior when 

 dead, as if it had been their parent. To en- 

 ter into the philosophy of this subject, and to 

 study the organs and faculties of these va- 

 rious insect tribes, in their functions of re- 



