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Life History and Habits. 
There is but one brood of this insect in a year, and it passes the 
winter as a larva in the stubbed twigs remaining on the tree. It 
pupates from the middle of April to the last of May, within the 
larval burrow, the outer end of which is closed by a wad of chewed 
wood, and here also the pupa changes to the adult, beginning about 
May lo. The beetle does not eat its way out of the burrow, but 
escapes by pushing out the terminal plug of the hollo wed-out twig. 
Pairing and egg-laying follow, from about jNIay 20 to the loth of 
June, accompanied by the amputation of twigs as already noticed. 
The beetles, male and female, die soon after the eggs are laid, and 
all are gone by the last of June. 
Mode of Oviposition. — It was observed by ]Mr. Titus in 1902 
that the female beetle first girdles the twig by cutting with her" jaws 
a groove entirely around it so deep that the twig is readily broken 
off. Below this she then cuts a longitudinal slit about an eighth to 
a fifth of an inch in length through the bark but not into the wood, 
and at the lower end of this she makes a shorter transverse slit, 
sometimes to the right and sometimes to the left, also merely 
through the bark. She now pushes the tip of her abdomen under 
the bark at the angle formed by the two slits thus made, and places 
her egg under the flap, where it can easily be detected by the slight 
elevation thus caused. She next retreats still further towards the 
base of the twig, and here girdles it a second time, nov^^ merely cut- 
ting through the bark, thus deadening the part beyond the girdle 
without causing it to fall. The effect of this complicated operation 
is to provide a safe lodgment for the egg, and so to arrest the 
growth of the twig that the egg shall not be crushed, the young 
larva finding, when it hatches, living wood at once available for its 
food. 
While the distance between girdle marks may be an inch or 
more, it averages about five eighths of an inch, and the egg-slits 
are made on the middle third of the space between the girdles. 
Where the beetles are superabundant, this operation mav be per- 
formed several times upon the same twig, by females unable to find 
each her separate branch for the deposit of her eggs. The result 
must be a serious loss of eggs, or of young larvae hatching from 
them, since only one of the- latter can continue and mature in a 
single twig. Although as many as eight or ten girdles may be 
found on a twig in June, never more than a single larva occurs in 
each the following spring. 
