REPORT OF THE E2iT0M0L0GIST AND DOTAMST 221 



SESSIONAL PAPER No. 16 



ral ears I am also sending. There are from one to three of tlic caterpillars in each 

 ear, and, of about 45 ears picked by me, so far only five were free from them. This 

 pest seems quite general here, and at least for eight or ten miles around. One man 

 only, of all I have asked about it, tells me that his corn is not affected. After a -while 

 the caterpillars make a round hole through the husk and disappear, I suppose, into the 

 ground, although I have vainly hunted for them in the ground about the corn roots.' 

 — Charles A. Hamilton. 



The caterpillar is somewhat variable in colour, and is from one and a quarter to 

 one and a half inches in length when full grown. The head is honey yellow, and the 

 body varies in colour from pale greenish to dark brown, and is marked with longitudi- 

 nal dark stripes and with a conspicuous band along the sides where the breathing pores 

 are situated. This band is white, mottled with pink. On the body are the ordinary 

 tubercles which are found on noctuid larvae. These are distinct and black, each one 

 bearing a slender bristle. The upper surface is marbled irregularly with white, and 

 the whole surface of the skin has a velvety appearance, owing to numberless very 

 short bristles, which are black and white in about equal numbers. A single specimen, 

 which turned out to be a caterpillar of this moth, was found in a greenhouse late in 

 the year (October 28). It was full grown and buried in the ground on October 31. 

 The jar containing it was kept out of doors for the winter, and the moth emerged on 

 July 8 the following year. This caterpillar was remarkably unlike those occurring on 

 corn the same year, being entirely dark velvety green, without conspicuous markings, 

 and was feeding on the leaves of a scarlet geranium. This moth, however, is by no 

 means a common species in Canada, and nearly all of the specimens I have seen have 

 been taken late in the year. Prof. Lugger states that the insect does not winter in 

 Minnesota, but that all are killed late in the fall. This, he points out, would mean 

 that the insect has to be reintroduced every siimmer from the south, where it can 

 successfully hibernate. "Whether the insect also hibernates as a moth in Canada, I 

 have been unable to decide, but it certainly passes the winter in some instances as a 

 pupa, although the caterpillars vary so much in size late in the year that many of 

 them must be caught by early frost, which destroys their food plant. The moth of 

 this insect is somewhat variable in the intensity of colour, but is usually of a diill pale 

 ochreous yellow, with olive or ruddy markings on tHe forewings. The yellowish hind 

 wings have a broad blackish band, and are edged with pink. These moths expand a 

 little more than an inch and a half from tip to tip of the opened wings. 



The caterpillars of the Corn Worm are recorded as having been found on a great 

 many different kinds of plants, including the following crops: Pumpkins, tobaccxf, 

 beans and peas ; and the full grown caterpillars seem to have a i)enchant for eating 

 into any solid firm object, such as a fruit or pod of any kind. 



Remedies. — Unfortunately this is a very difficult insect to keep in check. When 

 it attacks com, as described above, it is seldom noticed imtil a considerable amount 

 of harm has been done. Where the caterpillars are troublesome regularly every year, 

 growers, it is ckimcd, get into the way of recognizing at a glance, ears which are 

 infested, by the discoloration of the siUc earlier than is natural in perfect ears. As 

 soon as an infested ear is discovered, the leaves of the husk are pulled back and the 

 caterpillars destroyed by hand. Where, as in Canada, it is only at long intervals that 

 harm is done in any one place, corn growers are taken by surprise, and the injury is 

 done before it is noticed. It is claimed that many of the moths may be taken in 

 lantern traps consisting of a lamp standing in an open pan containing water with a 

 little coal oil on the top of it. Anyone, therefore, who knew the appearance of the 

 insect, upon recognizing the moths in years of great abundance flying around lights 

 at night, might place lantern traps as described above in his crop, and thus prevent 

 future loss; but this insect, like many others which appear in an intermittent manner, 

 will always be a source of trouble. On fields where a crop of corn is known to have 

 been attacked by the Com Worm, the old stems should be removed from the field as 



