STATE AGRICULTURAL SOCIETY. 
849 
POPLAR. LEAVES. 
ilie young insects hatching therefrom, puncturing and drawing their suste¬ 
nance from the same surface, cause the gall to increase gradually in its size, 
in the exact ratio in which the family within grow to require additional 
room. I observed no orifice in the smaller galls ; but when a portion of 
the inclosed insects have acquired wings and are ready to come abroad, a 
longitudinal slit is formed upon the under side of the gall, like a mouth 
with the lips closed, and the gall then has some similarity to a bivalve 
shell, as that on the European poplars has to a univalve. Through this 
orifice the flies coming out into the light of day, open their wings a few 
times to air and strengthen them, and then mount upon them and pass 
away. If two or three of the galls happen to be laid upon a table, on the 
adjacent window will soon be found a multitude of these flies which have 
been arrested in their flight outwards. As already stated, at least a por¬ 
tion of the flies which begin to issue from these galls the last of June, are 
females giving birth to living young instead of eggs. But their further 
history and in what state they pass through the winter and till another 
crop of leaves put forth for their accommodation yet remains to be investi¬ 
gated. 
In some instances two females fix themselves at the base of the same leaf, 
whereby their galls grow into each other, making an excrescence of double 
the usual size, in which are two cavities and two orifices. 
Secluded as these insects are within the tough leathery walls of these 
galls, they are but little molested by those numerous insect enemies 
whereby the forces of the Aphides are so often routed and infested vegeta¬ 
tion is cleansed from these pests. In one instance, however, the larva of a 
lady-bird ( Coccinella) was noticed standing like a vigilant sentinel at the 
orifice of a gall, occupying himself no doubt in seizing and devouring the 
flies one after another as they issued therefrom, before their wings had 
acquired the requisite suppleness to enable them to fly away. 
Although the leaves at whose bases these galls grow retain a healthy 
vigorous aspect till after the insects have escaped, they are undoubtedly 
weakened from having such an amount of their juice drawn away for the 
support of these galls and the insects within them, and will prematurely 
wither and fall from the trees. And when these insects become so numer¬ 
ous as they at present are around Albany, the trees will be enfeebled by 
them. But as it is merely the leaf stems which they infest, the life of a 
thrifty ti-ee will be jeopardized only by their continuance in force through 
a series of years, and that they will thus continue is not to be expected. 
354. Poplar oall-lodse, Pemphigus Popularia, new species. 
Late in autumn, wandering up and down the trunk of the Balsam pop¬ 
lar, a gall-louse closely like tho preceding, but its abdomen green, its 
antennae short, reaching but two-thirds the distance to the wing sockets, 
and tho rib-vein of its wings not thicker along tho inner margin of tho 
stigma; its length 0.13 to the tip of its wings. 
[Ag, Trans.] 34 
