THE GENERAL ENTOMOLOGICAL ECOLOGY OF 

 THE INDIAN CORN PLANT 



PROFESSOR S. A. FORBES 

 Illinois State Entomologist 



Ecology being the science of the interactions between 

 an organism, or a group of organisms, and its environ- 

 ment, and between organisms in general and their en- 

 vironment in general, this complex of relations may, of 

 course, be divided in various ways. The division here 

 used implies a centripetal grouping of the facts of rela- 

 tionship around single kinds of organisms, and the group 

 of facts to be discussed is that of which the corn plant is 

 the center and the insects of its environment are the 

 active factors. 



A prolonged study, extending over many years, of the 

 entomology of the corn plant, the economic results of 

 which have been published in my seventh and twelfth 

 reports as State Entomologist of Illinois (the Eighteenth 

 and Twenty-third of the office series) has left in my pos- 

 session a considerable body of information capable of 

 treatment from the standpoint of pure ecology, and the 

 beginnings of such a treatment are here assembled be- 

 cause of the rising interest in ecological investigation and 

 the promise which it gives of interesting and important 

 results, and because of a wish to illustrate, in some meas- 

 ure, the general scientific value of such materials, of 

 which, it scarcely need be said, the economic entomol- 

 ogists of this country have accumulated a large amount. 



Insect Infestation of the Corn Plant 

 We know of some two hundred and twenty-five species 

 of insects in the United States which are evidently at- 

 tracted to the corn plant because of some benefit or 

 advantage which they are able to derive from it. The 

 280 



