4 FARMERS’ BULLETIN 163. 
ings on the legs, about the head, and on the tips of the wing covers. 
In the spr ing ME om April to June, according to latitude, the beetles 
Fig. 3.—Galleries of the fruit- 
tree barkbeetle on twig un- 
der bark: a, a, Main gal- 
leries; b, b, side or larval 
galleries; ¢c, c, pupal cells. 
Naturalsize. (Ratzeburg.) 
appear on suitable trees and begin to excavate 
brood chambers between the bark and sap- 
wood. In preparing the chamber the female 
beetle gnawsaround hole, about one-twentieth 
of an inch in diameter, through the bark 
and then extends a shghtly enlarged burrow 
(fig. 8; a), 14 or 2 inches in length, nearly 
or quite parallel with the grain of the 
wood. This burrow or brood chamber is 
made partly in the bark and partly in 
the wood, and during the process of its 
construction small niches are mined out 
on both sides, in each of which a minute 
white egg is deposited. A single female 
will produce, on an average, from 75 to 
90 eggs. 
The eggs hatch in 3 or 4 days. The small, 
footless, grublike larvee are white with reddish 
heads and attain, when full grown,a length of 
about one-tenth of an inch. The larve (fig. 
2, 7d) burrow between the bark and sapwood, 
first at right angles away from the brood 
chamber, and form centipede-like figures in the wood which are dis- 
closed by removing the bark. (Fig. 4.) The larval burrows when 
Wig. 4.—Galleries of the fruit-tree barkbeetle under apple bark, showing adult females 
in brood chambers. Enlarged. (Original.) 
completed average 3 or 4 inches in length and are filled with dust- 
like frass of a reddish-brown color, After feeding from 30 to 36 
