70 



as well as Stark, and from information obtained from other sources, 

 we may conclude that they were pretty well distributed over the 

 northern portion of the State during 1880. On this, a writer from 

 LaSalle county in the Prairie Farmer says: "They have injured 

 the crop seriously in this eastern part of the county." 



But even with such accounts as these we might conclude, as we 

 had not known of it before, that it went into the corn-fields because 

 of its being more numerous than common, and that other plants 

 were its preferred food. As to which plant may constitute its chief 

 food it is not possible to say, from lack of observation on that point, 

 but we can form some opinion of what we may expect by what it 

 has done this season. Wishing to ascertain whether it was numerous 

 this year, inquiries were addressed to several parties in different parts 

 of the State, and I cull the following from some of their replies : 

 Dr. Boardman, under date of July 29th, 1881, says : 

 "In reply to your queries, I would say that the larvae of Diabrotica 

 Longicornis are at work this year, but not so extensively as last. I 

 know of a few fields being destroyed by them." 



He says again substantially the same, under the date of September 

 5th. 



Mr. Webster's notes on the insect for this year have been given 

 in another place. Others speak of grubs and wire-worms injuring 

 corn considerably, but in such a way as to lead us to suspect the 

 presence of Diabrotica, to which part of the injury may be attributed. 

 It is possible that, like the Chinch-bug and some other insects, this, 

 Diabrotica has periods of appearing and disappearing, depending 

 upon climatic changes, but upon that we can scarcely offer a con- 

 jecture now, because of lack of observation. The fact that it is less 

 numerous this year than it was last, in places where it did consid- 

 erable damage, is evidence that it has been affected by either the 

 climate, or insect, or other foes. 



The Corn Pioot-worms are, when at rest, from one-fourth to three- 

 eighths of an inch long, the body in its widest part about the size 

 of an ordinary pin. The anterior part is more slender than the 

 posterior part, the head being quite small, the body slightly depressed. 

 The skin is soft and smooth, with the exception of a few very small 

 white hairs. The color is white, with a slight yellowish tinge, the 

 head, feet, cervical shield and tip of anal segment brownish. 



While in confinement they showed themselves to be quite active, 

 crawling over objects almost as readily as caterpillars, even up the 

 sides of a glass dish in which they were confined. 



The enlarged figure of Diabrotica Vittata, published in several of our 

 books, so well represents this larva that it may be taken to illus- 

 trate it. 



The beetle, or perfect insect of this species, is about the size and 

 shape of the Striped Cucumber-beetle (Z). Vittata), being about one- 

 fourth of an inch long, but it differs very much in color. While the 

 Cucumber-beetle is yellow, with black stripes, D. Longicornis is nearly 

 a uniform dull, pale-green. Say, who named the species, gives the 

 following description of it : 



"Body pale-greenish ; eyes blackish; antenna; as long as the body; 

 second and third joints conjointed, shorter than the fourth; thorax 

 subquadrate ; two dilated oval impressed spots placed rather behind 



