10 BULLETIN 352, U. S. DEPARTMENT OF AGRICULTURE. 
THE ADULT BEETLE. 
Reaching the adult stage in the late summer and early fall, the 
beetles feed for a few weeks, and then seek out a protected situation 
in which they pass the winter. According to Pettit (1904) the beetles ° 
pass the winter several inches below the surface of the ground. 
Emerging from hibernation in the spring, they feed again for some 
time, mate, and the females descend to the base of the trees, where, 
among the decaying leaves and other vegetable matter, they deposit 
their eggs. Occasionally they utilize for this purpose accumulations 
of rubbish in the cavities in the bark of large trees. In such situa- 
tions eges have been found as high as 4 feet above the ground. 
INCUBATION PERIOD. 
No definite data on the incubation period were obtained, but on 
August 3 and 5 two lots of eggs were collected and placed in vials with 
the rubbish on which they were deposited. Most of those of August 3 
had already hatched, but young larve continued to emerge until 
August 14, 11 days after the collection of the eggs. This lot was col- 
lected on the hills about 4 miles back from thelake. The lot of August 
5 was collected only about a mile from the lake, and included a much 
smaller percentage of hatched eggs. This lot continued to produce 
larve until August 18, 13 days after collection. These figures are 
probably very near to the incubation period for the season of 1915, 
since Chittenden (1899) records a period of 11 days in 1898 at Wash- 
ington, D. C. 
THE LARVA. 
In hatching the larva cuts an irregular slit in one side of the egg. 
It then ascends the tree, and, feeding on the underside of the leaf, 
grows very rapidly. During its feeding period it molts twice. In 
molting the skin splits down the middle line of the thorax, the split 
extending on to the head, where it divides and extends to each side 
of the mouth. The head, thorax, and appendages are withdrawn, 
and the larva secures a hold on the leaf with its feet and crawls out 
of its old skin, which remains for some time fastened to the leaf. 
Furst instar.—In the course of the life-history work 243 larve were 
carried through the first instar. Of these 79 required 4 days; 140, 
5 days; 17, 6 days; 5, 7 days; 1, 10 days; and 1,11 days. This gives’ 
an average period for the first instar of 4.83 days. The first of these 
hatched on August 5 and the last molted for the first time on August 
24, this being the period in which all the data on this instar were ob- 
tained. Table I summarizes these data. 
