380 
Journal of Agr icultural Research 
Vol. XXVIII, No. 4 
THE EGG 
DESCRIPTION 
The egg (PL 1, D) of the cambium curculio is somewhat variable in size and 
shape. Average specimens are oval, 0.7 mm. long by 0.4 to 0.45 mm. wide. 
The color is translucent white, with a 3 'ellowish tinge, the surface is slightly 
wrinkled, and the contents of the egg are plainly visible through the shell. 
OVIPOSITION 
Jenne states that eggs on peaches are deposited in the fuzz, the skin never 
being punctured. The writer observed that caged beetles would oviposit in the 
fuzz of peaches and on the downy surface of young apple shoots, but no eggs 
were found on the smooth skin of apple fruits nor on smooth apple bark. When 
fresh twigs were placed in the cages with slits cut in the bark the beetles would 
oviposit in the slits in preference to any other location. Whenever eggs were 
placed on a fuzzy surface the beetles would draw a little of the available 
fiber around the eggs. Many eggs were found partially embedded in the moist 
fiber of the inner bark around fresh wounds in trees. Jenne states that of 88 
eggs observed all were laid in the night and 41 hatched in the night. 
INCUBATION 
At Gainesville, Ga., Jenne made observations on the incubation period of 188 
eggs, the results of which are set forth in Table I. 
Table I .—Incubation period of 188 eggs of the cambium curculio at Gainesville , 
Ga., in 1910 
Number of 
eggs 
hatching 
Duration of 
period 
22 
Days 
2 
58 
2.5 
67 
3 
27 
3.5 
13 
4 
1 
4.5 
The average time required for hatching was 2.87 days. The first of the lot of 
188 eggs was laid on May 20 and the last on July 10, oviposition therefore extend¬ 
ing over a period of 52 days. Eggs laid early in the season were slightly slower 
in hatching than those laid late in the season. The 24 eggs laid in May required 
on an average 3.5 days to hatch, while the 13 laid in July required 2.79 days 
to hatch. The increasing warmth of the advancing season probably accounts 
for the shortening of the incubation period. Numerous eggs laid in West Vir¬ 
ginia hatched in from 3 to 4 days. Jenne kept an egg record of seven beetles, 
but he does not state whether they were all females. The lot produced 188 
eggs, an average of 26.86 each if they were all females. 
THE LARVA 
DESCRIPTION 3 
Mature larva of Conotrachelus anaglypticus (Pis. 2 and 3) from 7 to 9 mm. in 
length and from 1.5 to 2 mm. in width. Body white, fleshy, and legless, almost 
cylindrical but somewhat flattened ventrally. Ten abdominal segments, the 
ninth reduced and flattened, the tenth small and ventral. 
3 By R. T. Cotton. 
