12 



1. The Eoot Web Worm. 



{Cramlms zeellus, Fernald.) 



Order Lepidoptera. Family CRA.MBiDiE. 



(Plato I. Figs. 1-3.) 



The discovery of an insect new both to science and to agricul- 

 tural entomology, and capable of serious injury to the most im- 

 portant crop of the State of Illinois, is, fortunately, at this date an 

 unusual event, so thoroughly, of late years, has the ground been 

 scanned ; and yet, long as is the list of insect enemies of Indian 

 corn, v/e have no reason to suppose that it is yet complete. 



The balance of animal life is continually shifting, even in old and 

 long-settled countries, species formerly rare or unknown coming to 

 the front, and others formerly abundant and perhaps destructive, 

 retiring temporarily from view. Not only do insects of other regions 

 invade our own territory, but a peculiar collocation of circumstances 

 often favors the undue multiplication of some one or more of our 

 native species, with the result to convert an insect harmless from 

 its rarity, into a very serious obstacle to the success of agriculture ; 

 and it is to be noted that having once reached this dangerous 

 prominence, it is a rare thing for an insect to permanently lose its 

 hold on the agricultural products of the country. 



In respect to the species treated in this article, we may at least 

 congratulate ourselves that it has been detected early in its career, 

 before it has reached really dangerous numbers, and prompt and 

 thorough study of its economy and of its life history may give us 

 the means of controlling it before it can do serious mischief. 



On the 7th June, 1883, my assistant, Mr. Webster, who had been 

 detailed to study the work of the black-headed grass maggot in 

 corn fields*, brought to the office some supposed cutworms — bristly 

 reddish larvae, which he had found gnawing the roots of corn below 

 the surface, in fields in McLean county, on both old and new 

 ground. 



They were not seen again during this season, but on the 19th 

 May of the present year I received the same species from Mr. E. 

 A. Gastman, superintendent of public schools at Decatur, with the 



* See ISth Eeport of the State Entomologist of Illinois, pp. 57-59. 



