TIME OF APPEARANCE OF BEETLES IN SPRING. 113 
and Dr. Harris (loc. cit., p. 67) remarks that they begin to sting 
plums as soon as the fruit is set. 
Dr. Fitch (Essay, p. 16), writing in 1860, states that the insects 
make their appearance on plum trees when the young fruit is about 
one-third or one-half grown. The question was well investigated by 
Dr. Trimble (loc. cit., p. 72) in Xew Jersey in 1864, and frequent 
jarrings were made beginning May 12, at which time quince trees were 
in full bloom and green gage plums were just forming. Three beetles 
were caught from plum on May 13, 1 on May 18, and 10 on May 20 
on knots of cherry and plum. Curculio punctures were in evidence on 
pears and cherries on May 18 and on plum on May 19. 
Walsh (Prac. Ent., vol. 2, p. 75) states that the female curculio 
makes her appearance early in the season, and as soon as the young 
plums are a little larger than a hazelnut. 
According to Dr. Riley (loc. cit., p. 53) the beetles in central 
Missouri begin to enter orchards during the first days of May, and 
commence to penetrate the fruit about the middle of the same month, 
varying with the season, peaches at this time being about the size of 
a small marble. 
Riley (Amer. Ent., vol. 2, p. 131) further states that the curculio 
commences to puncture peaches when they are the size of small 
marbles or hazelnuts, though she may be found in the trees as soon 
as they are in blossom. 
This point is not touched upon in the excellent account of this 
insect by Riley and Howard in the Annual Report of the Commis- 
sioner of Agriculture for 1888, though in the colored plate accompany- 
ing the article the weevils are shown on 'a plum twig, the buds of 
which are not }^et expanded. 
Lintner (11th X. Y. Rept., p. 122), writing in 1895, says that the 
plum curculio enters upon the scene at least two weeks before its 
first crescentic cuts are made in the fruit. 
More exact data are presented by Prof. Crandall (loc. c it., p. 495) 
in his studies of the curculio in Illinois, in 1903 and in 1904. Thus, 
during the spring of 1903 apple trees were carefully searched at fre- 
quent intervals, but no beetles were found until May 10. when they 
were abundant, appearing to come all at once. Apple buds were 
opening by April 16, the trees were in full bloom April 22, and the 
petals had practically all fallen by May 4. The beetles, therefore, 
were not in evidence on the trees until a week after the blossoming 
period, coining suddenly in large numbers. In the spring of 1904, 
systematic jarring of two trees was begun April 28. One beetle was 
taken from tree No. 1 on May 4, 1 on May 5, 5 on May 7. and subse- 
quently, a total of 15 by May 19. On tree No. 2 the first beetle was 
taken on May 17, and 1 the day following. On other trees beetles 
wero taken May 7, and a few subsequently during the month. Apple 
17262°— Bull. 103—12 8 
