THE STATE ENTOMOLOGIST. 97 



•of. a light brown color. The sexes are now distinguishable, the male 

 chrysalis (Fig. 66, e) being slender, pointed in front, and showing the 

 wing-sheaths ; while that of the female is larger and destitute 

 •of wing-sheaths. 



In the latitude of St. Louis, the worms have generally descended 

 from the trees and entered the ground by the middle ot May, though 

 some remain till about. the first of June. As I have amply proved 

 during the past two summers, there is but one brood each year in this 

 State, just as there is but one brood in Maine, and whether the worms 

 enter the ground the first or the last of May, they remain there as 

 chrysalids all through the summer and fall months, and the great 

 majority of them till the following spring. A frost seems to be neces- 

 sary to their proper development. Some come out during the first 

 mild weather that succeeds the first frosts in November; others issue 

 all through the winter whenever the ground is thawed, and the great 

 bulk issue as soon as the frost is entirely out of the ground in spring. 

 Many which I bred this winter issued during the warm weather of 

 January. 



The moths (Fig. 66 f <5,g $ ) show great disparity of sex, the male 

 being fully winged while the female is entirely destitute of these ap- 

 pendages. The front wings of the male are pale ash-gray, crossed by 

 three equidistant jagged, more or less defined, black lines, all curved 

 inwardly, and most distinct on the front or costal border; and by a 

 somewhat broader whitish line, which runs from the posterior angle 

 to the apex; the inner and terminal borders also being marked with 

 black. The hind wings are silvery-gray, and the under surfaces are of 

 the same uniform silvery-gray color, each wing with a dusky discal 

 spot, the front wings each with an additional spot on the ccsta. Such 

 is the appearance of the more common perfect specimens found in 

 the West, but the wings are very thin and silky, and the scales easily 

 rub oft", so that it is almost impossible to capture a perfect specimen 

 at large. They vary considerably also — so much so that Dr. Harris 

 ranks a smaller form as a distinct species (A.pometaria) which I have 

 however bred promiscuously with the more typical specimens. The 

 most common variation from the brief description above given, is 

 found in such specimens which have the dark lines obsolete, and an 

 additional white line inside the one described. The female is ash- 

 gray, the thorax with a black spot, the body more or less marked 

 with black along the back, and the legs alternately marked with black 

 and white. 



In Missouri the Canker-worm is not so injurious over broad tracts 

 of country, as it is in some of the more eastern States. Yet it is suf- 

 ficiently distributed in different parts, to require vigilance to keep it 

 down. "R. P.," of Mexico, Mo., found it very injurious in the spring 

 of 1868, and sent me many specimens, and they were the genuine 

 article. Around Pevely, I have likewise found it common on the 



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