OUTLINES OF ENTOMOLOGY. 21 



Others, like the butterfly and wasp, have a very different diet from that 

 upon which they subsisted as larvje. Some species, however, such as 

 locusts, leaf-eating- beetles, etc., retain their voracious propensities 

 throughout life. 



Hyper-mctaniorpJiosls, which attends the development of a few 

 ■species of parasitic beetles and some flies of the Ephemera family, is 

 the assumption of more than the usual number of forms in the process 

 of growth. The transformations of such species are not invariably 

 from a lower to a higher organization, but some of the intermediate 

 stages are often of a retrograde character. This anomalous mode of 

 development will be illustrated in succeeding chapters in connection 

 with the history of the Blister beetles, Bee parasites and Kerve- winged 

 :flies. 



Such is an outline of the history, continually repeated, of all insect 

 life; but the number of species is so vast, and their forms and habits 

 so different, that the careful observer finds an infinite variety of detail 

 which gives continual novelty and interest to the subject. 



