372 
Journal of Agricultural Research 
Vol.XI, Nt 3 
in the branches by fig canker, 1 injuries in the bark, etc. For example, 
a fig tree on the laboratory grounds at New Orleans, which through 
faulty pruning a comparatively light wind had caused to split down 
through the head, became so severely infested that it was estimated 
there were more than 1,700 borers in it at one time. Another fig tree 
which had been perfectly healthy and free from borers became severely 
infested in the trunk soon after the bark had been injured by a mer¬ 
curial band applied to keep out ants. Still another healthy tree first 
became infested after a windstorm had broken off one of the larger 
branches, the eggs all being deposited in the branch from which it was 
broken, not far from the wound. 
Every one of the six or eight injured or diseased fig trees on the lab¬ 
oratory grounds at New Orleans became heavily infested with borers, 
whereas not a single egg or borer could be found during three seasons 
in any of the 8 or 10 well-formed, healthy trees growing near them in 
the same yard. It may therefore be set down as a practically infallible 
rule that if the fig trees are kept in a thriving healthy condition, they 
will not be subjected to severe attacks, and may escape any injury 
whatever from the three-lined fig-tree borer. 
BIOLOGY AND HABITS 
THE EGG 
description and place where pound 
The egg (Pi. 35, A) is an elongate, nearly cylindrical, pure white to 
faintly yellowish or greenish object, ranging from 0.026 inch (0.66 mm.) 
to 0.039 inch ( I mm.) broad, from 0.128 inch (3.25 mm.) to 0.144 
inch (3.66 mm.) long, being on an average 0.036 inch (0.916 mm.) broad 
and 0.138 inch (3.52 mm.) long. The shell is often more or less distinctly 
patterned like the grain of the fig wood in which the egg is deposited. 
The eggs are deposited by insertion into the bark of the larger branches 
and trunk, thus being completely hidden from view and protected by 
the bark. They are usually deposited near wounds or decaying spots 
in the bark, or in limbs which have been cut or broken. They are even 
deposited in large branches which have been removed from the tree. 
They are seldom or never found in perfectly sound, healthy bark, a 
fact of importance in controlling the borer. The eggs usually occur 
singly, but sometimes two, three, or five are found together. 
INCUBATION 
The incubation period of eggs of the fig-tree borer does not vary greatly, 
at least in the period from May to September, when most eggs are develop¬ 
ing. The maximum time required for the eggs to develop, as recorded 
in the season of 1914 and 1915, was 8 days, the minimum 3 days, the 
1 Edgerton, C. W. diseases of the fig tree and fruit. Ea. Agr. Exp. Sta. Bui. 126, p. 10-12, 
pi. s- 1911* 
