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kind of plant-food. Dr. Harris speaks of having raised it from 
caterpillars found feeding upon the elm, but makes no mention of 
its eating the currant. Dr. Fitch, in his New York Reports, 
speaks of them as sometimes eating the leaves of the currant, and 
on the 15th of July I received a number of these caterpillars from 
Mr. B. N. McKinstry, of Judson, Kaukakee county, accompanied 
with the statement that they were doing considerable mischief by 
stripping the leaves from his currant bushes. This is, I believe, 
the first record of its feeding upon the currant in this State, and 
it cannot be regarded, at present, as a noxious insect of a serious 
character. 
I made a few observations upon the individuals sent to me, of 
some scientific interest, which I will briefly state. 
The chrysalis state, which is stated by Drs. Harris and Fitch to 
vary from eleven to sixteen days, lasted, in my speimens, only 
seven days. The weather was excessively hot, the thermometer 
indicating, most of the time, 100 degrees, which may, perhaps, 
account for the rapid development. 
As these caterpillars, after they had suspended themselves for 
the purpose of transformation, hung directly in front of my study 
table, I was led to observe more closely than I had hitherto done, 
the process by which these creatures divest themselves of their 
larval covering. It appears to consist of two stages: the first is 
slow, gradual and almost imperceptible, occupying some twenty- 
four hours of time, during which, it may be presumed, there is 
effected a gradual separation of the larval from the pupal envelope. 
During this period the caterpillar hangs with its body curved for¬ 
wards and upwards, and appears to be almost motionless ; but upon 
close observation it is seen to undergo almost continuous though 
slight changes, consisting of a nodding motion of the head, and an 
occasional variation in the curvature of the body. The second 
stage is short and active, usually lasting but a few minutes, the 
object of which is to throw off the loosened larval skin ; first, by 
bending the body it bursts open the skin upon the back, and then, 
by a wriggling motion, works it up towards the point of attach¬ 
ment, and lastly detaches and throws it entirely off by a series of 
violent contortions, apparently at the imminent risk of severing 
the thread upon which its safety literally depends. 
