37 
[ 297 ] 
* 
rapidly that I had some difficulty in keeping it within the field ot 
the lens. As soon as it paused long enough to be examined, it 
was easily recognized as a Chalcis by its general aspect, and espe¬ 
cially by the peculiar vibratile motion of its short, geniculate 
antennse. 
Having once become familiar with its appearance, I have had 
no difficulty in capturing, in the latter part of August and Septem¬ 
ber, all the specimens I desired on the infested trees. I have 
repeatedly watched the female Chalcis in the act of inserting her 
ovipositor through the scale of the Bark-louse, for the purpose of 
depositing her egg in the cell beneath. She always places herself 
transversely with respect to the scale. Sometimes she mounts 
upon it, and then her tiny body is seen to be considerably less in 
length than the width of the scale. Usually she backs up upon it 
only so far as to bring the tip of her abdomen about opposite the 
middle of the scale. Then bringing her ovipositor down perpen¬ 
dicular to her bod} 7 , she forces it through the scale by a series of 
boring or short plunging motions. Having accomplisned this she 
remains stationary for many minutes, whilst by some invisible 
intestine motion the egg is carried down the ovipositor and deposi¬ 
ted beneath the scales. So absorbed is she in this delicate opera¬ 
tion, upon the successful accomplishment of which not only her 
own hopes, but those of the horticulturist, so largely depend, that 
nothing can deter her from it. In one instance, having drawn 
down a branch of an apple tree, I discovered a Chalcis in the act 
of depositing. Whilst holding the branch in one hand and view¬ 
ing the insect through a lens held in the other, the branch slipped 
through my fingers and flew back with violence to its place. 
Drawing it down again, the twig I had hold of broke, and it flew 
back a second time. I supposed that that observation had, of 
course, been brought to an abrupt termination. But, upon draw¬ 
ing down the limb the third time, there stood my little Chalcis as 
immovable as a statue, at her post. She may be touched with the 
finger whilst thus engaged, or even crushed, as I have often inad¬ 
vertently done in my attempts to capture her, but nothing short 
of this actual violence can move her from her position. With such 
wonderful perseverance and devotion do these living atoms of 
creation perform their allotted part in the complicated economy of 
nature. 
