6 BULLETIN 1066, U. S. DEPARTMENT OF AGRICULTURE. 
s 
ADI'LT. 
The beetle (PL I, A, B\ and C) resembles very closely the common 
plum curculio. being brownish gray with a variable, whitish, curved 
line on each side of the thorax and a broad whitish band behind the 
middle of the elytra. The back is marked with prominent humps and 
ridges and is covered with short gray and whitish pubescence. The 
strong curved beak is nearly half as long as the body, and the body, 
exclusive of the beak, averages about 7 mm. in length. The general 
appearance of the beetle is rough and angular. 
The young beetles issue from the soil in late summer and early 
autumn, 64 individuals issuing in TTest Virginia between August 17 
and September 6. Of these beetles the maximum daily emergence of 
13 took place on August 27. A few beetles continued to come from 
earth in rearing jars up to the middle of October. These young 
beetles reach the trees before those of the parent generation have all 
died, and, like them, feed sufficiently in the autumn on the surface of 
terminal shoots and leaf petioles to suggest their destruction with 
arsenical sprays in September or early October. The beetles go into 
hibernation, probably in litter on the ground, with the approach of 
freezing weather. 
The beetles issue from hibernation in the spring at about the time 
walnut trees come into bloom and resort at once to their host trees. 
They may at this time be jarred in abundance from butternut trees, 
a few having been taken in West Virginia by jarring black walnut 
and hickory trees growing near butternut trees. With very few ex- 
ceptions, however, the species jarred from black walnut at this season 
of the year has been C. retentus and those from hickory C. aratu*. 
This usually holds good even where the three kinds of trees grow in 
close proximity. 
Feeding begins in a limited way soon after the beetles appear on 
the trees, the food consisting of stem and leaf tissues of the new 
growth. The feeding marks in the stems are in the form of irregu- 
lar pits reaching through the bark and are sometimes extensive 
enough to cause the leaves and tips to droop and die. Oviposition 
soon begins, the first eggs being laid in the new growth which forms 
before the fruit is large enough to be attacked. In the native butter- 
nut most of the eggs are withheld until the nuts are large enough to 
receive them, this being when the nuts are about an inch long. In 
young and tender nuts practically all the eggs are placed in crescent- 
shaped marks eaten into the husk near the blossom end. (PI. I, E ; 
PL II, A.) By means of an extrusive ovipositor the egg is thrust 
into a small pocket excavated beneath the tongue of skin on the con- 
cave side of the crescent. The beetles are often found resting upon 
the remnants of the blossom that project from the tip of the young 
