130 THE PLUM CURCULIO. 
But later he complicates the subject by his conclusion that the 
curculio is double-brooded, and that it is the beetles of this second 
brood that survive the winter. On this point of hibernation Riley, 1 
in a summary statement concerning the knowledge of the insect at 
that time, states — 
That the greater portion of them pass the winter in the perfect beetle stage under 
the old bark of both forest and shade trees, under shingles and logs, rubbish of all 
kinds, and especially the underbrush of the woods. 
That a certain proportion of them also pass the winter underground, both in the 
larval and pupal stages, at a depth frequently of from 2 to 3 feet. 
That those which hibernate as beetles begin to leave their winter quarters and 
enter our orchards throughout central Missouri during the first days of May, and com- 
mence to puncture the fruit about the middle of the same month — a little earlier or 
later, according to the season — the fruit of the peach being at the time about the size 
of a small marble. 
However, Riley, in his Third Report (p. 13), expresses a different 
opinion, and says that he has satisfied himself that the curculio 
invariably passes the winter as a beetle under shelter of all sorts 
near the surface of the ground. This conclusion seems to have been 
adopted by nearly all subsequent writers. There has been, how- 
ever, little exact information on the places where the curculio hiber- 
nates, and indeed little direct effort has been made to find them in 
hibernation. 
Prof. Crandall (loc. cit., p. 495) reports results of searches for 
beetles in Illinois in the spring of 1903. On March 31a whole day's 
search revealed none. Search was made again on April 14, and at 
intervals up to April 27, when first beetles were found under dead 
grass on the ground and occurring singly. Examinations of the 
trees in spring did not reveal the beetles until May 10, when they 
appeared to come all at once, none having been found on the day 
previous. Further search of hibernation quarters, in 1904, was 
made by Prof. Crandall, but no beetles could be found. 
The hibernation habits of the curculio have been investigated at 
various times during the course of the present study of the insect. 
At Youngstown, N. Y., in 1905, Mr. Johnson made frequent searches 
in the fall during October, and on the 14th of that month 9 
beetles were discovered in a slight depression under an apple tree. 
They were well covered with closely matted, well-decayed leaves 
within a space about 2 inches square. Nine more beetles were 
found in a similar situation in an apple orchard on the 16th. On 
October 25 an examination of an uncultivated orchard in light soil 
revealed none, but in an adjoining orchard where there was a sparse 
covering of sod and leaves on the ground, 6 beetles were taken, 4 
being quite dormant and 2 capable of moving feebly. A search on 
November 4 among leaves on the ground in an apple orchard failed 
i First Missouri Report, p. 53 
