11 



threads some distance above the root. Some webs are placed ver- 

 tically, lying close beside the stem. They frequently occur under 

 clods, and occasionally one was seen scarcely protected at all. 



The injury to the corn is extremely characteristic, and cannot be 

 mistaken when once understood. The web worm evidently leaves its 

 burrow to feed upon the leaves, at first the lower one and then those 

 nearer the top of the stalk, commonly eating off the ends of the leaves 

 or gnawing irregular holes near the middle of the larger ones. The 

 lower leaf of the infested plant is ordinarily eaten wholly away. 

 Occasionally I have found a leaf cut off and drawn partly into the 

 burrow of the worm ; and sometimes the kernel of corn was eaten in 

 the ground. The stalk of the affected plant will be found gnawed ir- 

 regularly beneath the earth, sometimes wholly severed, as by a cut- 

 worm, but more commonly scarified, or bored lengthwise, either super- 

 ficially or through the centre of the stalk. From one to eight or ten 

 larvae may be found in a single hill. In a field near Champaign, on 

 land in pasture for fifteen years, plowed up about May 5 and planted 

 to corn from five to ten days' thereafter, I found the corn so badly 

 injured by this insect that the owner had decided to replant the 

 greater part of it. No difference in amount of injury could be cor- 

 related with difference in soil or surface, the worms being aB abund- 

 ant on low ground as on high, and as indifferent, seemingly, to 

 character of soil. ^ 



Near Mount Pulaski, June 16, we found a field of corn which 

 had been practically destroyed by this insect about two weeks be- 

 fore, and had consequently been plowed up and replanted. This 

 field had been in pasture for a number of years and Avas broken up 

 for the first time the preceding fall. The web worms had 

 not, apparently, been seriously disturbed by the replanting, but had 

 already attacked the young corn of the second growth, and to this 

 were doing considerable damage. 



As the larvae in the Champaign field were, several of them, full 

 grown, and the greater part of them nearly so, it is certain that the 

 eggs were laid in the sod before it was broken up. The root web 

 worm consequently breeds in grass. This view is confirmed by in- 

 formation concerning this insect from J. P. Norton, of Libertyville, 

 Lake county. A field of twenty acres, plowed up from greensward 

 in spring and planted to corn, was said by him to h:ive been im- 

 mediately cut down by the root web worm as it came up, and the 

 webbed larva was found, in each case, just below the surface, about 

 the roots of the corn, not missing, nccording to his report, a single 

 hill. On the other hand, Mr. E. 8. Mills, of Dwight, Illinois, (in 

 whose field I first studied the species, two years ago,) writes me that 

 the ground upon which the corn was injured had been alternately 

 in corn and oats for six preceding years, and for three or four years 

 before that, in corn. 



The species was sent us last year from various localities in 

 Henry, McLean, Mason, and Livingston counties, and doubtless oc- 

 curs everywhere throughout central Ilhnois. From the Crop Eeports 

 of the State Department of Agriculture, I learn that this insect, a 

 description of which had been but recently published, was noted by 

 •the crop reporters of the Department in Carroll, Cass, Stark, and 



