127 
toward upper and one toward lower margin. Mons. V. Segnoret, says 
in his essay on Lecanides, that in the place of the lower pair of wings, 
there are two bent halters or ballancers, which I have been unable to 
discover in the mounted specimens of acericola before me, although it 
is highly possible they may be found in fresh specimens. 
To recapitulate, we find the Lecanium acericola is single brooded, the 
females living a few weeks over one year, the eggs deposited the lat¬ 
ter part of May and the young lice appearing three weeks and a half 
after. They settle down, at once, upon the leaves of the tree, and 
remain until autumn, when they return to the under side of the 
limbs, remaining in this assumed position the rest of their lives. 
The males appear in eight weeks after the young have hatched and 
the females are then fully developed; in two or three weeks the males 
disappear entirely. The females remain dormant on the limbs six 
months and a half of the entire year. 
It is well known that the varied temperature has great effect upon 
the length of time the insects remain in their several stages of 
growth. 
The notes here recorded were taken during the years 1876 and 1877, 
and it is possible a warm spring may hasten the developement of the 
egg and cause the young insects to appear earlier than here recorded. 
Comparative statements ought be made after many years observa¬ 
tion, and such I hope to make in time. The insect is wide spread 
throughout Northern Illinois, and extends to the Atlantic from where 
I have received specimens and information from reliable sources, and 
my observations have led me to different conclusions than those given 
by Walsh and Riley, since in all instances thus far have I found the 
females with the egg-mass and eggs upon the limbs of the tree, as 
represented in Fig. 28, a, and not upon the expanded leaf, although 
it is possible if the season were long enough the eggs might be 
found upon the leaf. I have either visiteu personally or received 
specimens from the following places wherein the eggs were deposi¬ 
ted on the limb during the months of May and early June: 
Bloomington, Le Rov, Genesee, Rock Island, Havana, Kewanee, 
Peoria, Illinois, and Davenport, Iowa. In one instance I have found 
the acericola upon a box-elder tree in Peoria, but only in a limited 
number. 
Modes of Spreading .—The way in which this insect is conveyed from 
place to place is undoubtedly through the transportation of the trees, 
the scales of the female adhering to the limbs when transplanted. 
The insects spread from tree to tree by the aid of the wind when in 
the egg state, the waxy mass becoming detached from the tree in very 
stormy weather, and being light is easily blown about. Many flies, 
wasps and bees are attracted to the trees by the sweet substance in 
the waxy mass, and the young lice, when crawling about before set¬ 
tling down upon the leaves, will become attached to the legs of these 
insects and thus conveyed to other trees. 
One occurrence was noticeable, during the past summer, and worthy 
of mention, the cause of which I was wholly unable to account for. 
Four miles north of Kewanee, Illinois, in the midst of a walnut 
grove, close by a farm house, were a few soft maple trees, grown from 
seed. On one of the trees not over six feet high I found the female 
I 
