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fields in every possible situation. I have found them not only de- 

 nuding the ears of corn of silk, but actually eating the kernel, it 

 being in a state of hardening. To tell you the truth, I have graver 

 fears of this insect in the future than I have of the Chinch-bug. 

 Up to the first of August I had not noted them in any numbers." 

 Putting this with two communications from the same writer of an 

 earlier date, we have confirmation of Dr. Boardman's conjecture, 

 that there are more than one brood of the beetles in a season, a 

 point we shall want to notice further along. August 8th, 1881, Mr. 

 Webster says : 



"The Diabrotica Longicornis has not put in an appearance ; have 

 not seen a single imago this season." 



Under date of September 10th, 1881, he writes again : 



"I believe this insect is now at work, but I cannot find the worms. 

 Corn is withering about the edges of the fields and on high gravelly 

 knolls. I have had but one opportunity to examine, and found all 

 the brace roots destroyed, and found only one insect at work, and 

 that a small green worm which I have sent to Miss Middleton." 



It may be well, before giving items from any more letters, to go 

 over some of the points already brought forward. 



That this species of Diabrotica is, if anything, a more general 

 feeder than D. Vittata seems to be pretty well established by the 

 several observers whose notes we have. According to Dr. Boardman, 

 in the perfect state it feeds readily upon the pollen of several com- 

 posite weeds, the silk and soft kernels of corn, and cucumber and 

 other vines ; while the larvae have been found by him feeding upon 

 the roots of corn and ragweed, and we do not know but they, may 

 feed upon the roots of any plant whose leaf or pollen or other por- 

 tion of the top furnishes food for the beetle. Prof. Forbes confirms 

 the pollen-eating habit of the beetle, while Mr. Webster attests to 

 finding it eating kernels of corn. As before said, I have found the 

 beetles eating my beans. As to the number of broods in a season, 

 we have good reason to infer that there are two or more. I received 

 the larvae spoken of in Dr. Boardman's letter July 31st, 1880. Some 

 of them were, to all appearance, ready to pupate. If they did change 

 within the next few days, and hatched August 17 and 18, that would 

 give us a pupal period of about two weeks, or the same as the 

 striped beetle D. Vittata. We are told that it is about a month from 

 the time that the egg of the last named species is deposited at the 

 roots of the cucumber vine till it is ready to pupate ; and that the 

 pupal period lasts two weeks, making six weeks from the egg to the 

 perfect insect. As the D. Longicornis has the same pupal period and 

 a similar habit, it is fair to presume that it takes about the same 

 time for it to go through with its transformations, or that there are 

 from two to three broods in a season, the last probably passing the 

 winter in the ground in the pupa state. The striped beetle deposits 

 its eggs near the roots of cucumber and squash vines, and the fact 

 that the larvge of this one have been found in the roots of corn, and 

 of such weeds as furnish food for the beetles, is almost conclusive 

 proof that it has the same habit of depositing its eggs. Very natur- 

 ally we should ask of the extent of injury done by this insect, and 

 are we to apprehend danger from it in the future? From Dr. Board- 

 man's statement that they did considerable injury in Knox county, 



