EIGHTH DAY.] ICHNEUMONS. 217 



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 caterpillars, 

 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 enter into the philosophy of this 

 subject, and to study the organs and faculties of these 

 various insect tribes, in their function of respiration, 

 nutrition, and reproduction, would be sufficient for 

 the labour of a life. To know what has already been 

 done would demand the close and studious application 

 of a comprehensive mind; and to complete this 

 branch of science in all its parts is probably almost 

 above human powers ; but much might be done if 

 enlightened persons would follow the example of 

 De Geer, Eeaumur, and Huber, and study minutely 

 the habits of particular tribes; and it is probable, 

 that physiology might be much advanced by minutely 

 investigating the simplest forms of living beings, and 

 that particularly with respect to the functions of 

 generation; a minute study of the modifications of 

 which the forms of animals seem susceptible, particu- 



