=o 
the thin, outer bark, which had apparently been broken by the wind. 
These pieces contained a larva, evidently of the same species as those 
previously observed ; and similar larvae, but no pup, were observed in 
the prostrate stems, on the 25th of the following April. From these ob-. 
servations, Mr. Coquillett opined that the beetles deposited their eggs in 
mid summer; the larvae, hatching in a few days, reached their full growth 
in three or four months, and, hibernating in the stems in that stage, chang- 
ed to pup early the following Summer, emerging as adults soon after. 
At the time Mr. Coquillett was making these observations, we, in 
dn adjoining County of the same State, were similarly engaged, although 
as ignorant of his studies as he was of ours. However, with the exception 
of securing more facts relative to the mode of oviposition, and the number 
of eggs, and the grouping of the egg chambers, we did not materially im- 
prove upon his observations, as afterwards published. 
In Northern Illinois, where we always found macer to be the most 
common species of Zzxuws, concavus seldom occured in our collections. 
In Central [linois, in 1882 and 1883, we found the latter to be the more 
abundant species, while the former was seldom observed. We were more 
surprised to here observe concavus ovipositing in the stems of Helianthus, 
exactly as we had observed its congener do in the Northern part of the 
State. | 
The female, of either species, in depositing her eggs, first places her- 
self, head downward, upon the stalk in which she intends to oviposit, 
and, without, moving the feet, commences a series of backward and for- 
ward movements of the rostrum, gouging out a narrow channel, varying 
from three-fourths to about an inch in length, penetrating through the 
woody portion of the stem to the pith. This channel is not clean cut, 
but is, when finished, filled with matted fibre, not detached and not easily 
removed. From near the upper end of this channel, the female next ex- 
cavatés a burrow, of the diameter of her rostrum, directly into the pith, 
for a considerable distance; thence upward as far as she can reach. 
While we have never observed the sexes 7 coifu, nor the placing of the 
egg, the male is almost invariably present 7 sz/w, and we have often 
interrupted the female in the midst of her work, and found an egg partly 
in place in the stem. These observations leave little room for doubt that 
the eggs are fecundated just prior to the act of oviposition, and dropped 
by the female at the mouth of the burrow, being afterwards pushed in 
place by aid of her rostrum. 
Wherever there was good evidence of the nidus having been com- 
pleted, we have always found a second chamber or burrow, at the lower 
extremity of the channel also, but not extending far enough upward to 
come in contact with the upper. In each of these chambers we have 
