10 BULLETIN 1066, U. S. DEPARTMENT OF AGRICULTURE. 
dries and hardens on the ground. When the larva is full grown it 
ceases feeding, assumes a clearer cream color, and, after a period of 
a week or two of inactivity within the nut, cuts its way out through 
the shell and enters the ground to a depth of from 2 to 4 inches to 
pupate. Larvae ma}^ be found in the nuts from early in June until 
late in September. In one lot of 805 larva? which issued from in- 
fested black walnuts kept in rearing jars the first larva left the nut 
on July 14 and the last on September 21. These larvae, like those 
of the butternut curculio, chiefly issued early in the morning and 
the largest numbers always in cool weather. In small green nuts 
only one larva matures to the nut, but two or three larvae may de- 
velop together in a large nut. Apparently where several larvae hatch 
and begin feeding in a small nut one individual always kills and 
devours the others. In two or three instances one larva was found 
killing and eating its fellow. On entering the ground the larva 
seeks a place where the soil is solid and fashions a smooth- walled 
cell (PI. IV, C; PI. V, Z>), where it rests for several days before 
pupating. 
PUPA. 
The pupa (PL IY, F ; PI. V, D) is white and is about 9 mm. long- 
by 3 mm. thick. The abdomen, thorax, and wing pads are covered 
thinly with short, stiff hairs, these hairs being shortest on the wing 
pads. The pupa occupies an unlined earthen cell from 2 to 4 inches 
beneath the surface of the ground. The pupa stage covers a period 
of from two to three weeks. 
The mature beetle (PL IV, A and B) is dull reddish-brown and 
covered with grayish pubescence. There is a lighter colored, in- 
distinct, broad band behind the middle of the elytra and a vague, 
broken line of the same lighter shade on each side of the thorax. 
The snout is half as long as the body and the back is ridged and 
punctured. The length averages from 6 to T mm. This beetle in 
size and general shape resembles very closely the butternut curculio 
but its color markings and elytral sculpturing are less pronounced. 
The newly developed beetles begin issuing from the ground in 
August; the first specimens were obtained in this investigation 
on August 7. In one rearing cage 75 beetles came from the ground 
between August 13 and September 2, the maximum emergence tak- 
ing place from August 24 to 29. 
In late summer and early autumn the young beetles may be found 
on their host trees, where they apparently feed on the leaf petioles 
before seeking their hibernation quarters. The beetles live through 
the winter, probably hidden in the duff at the surface of the ground, 
