1878. The Maple-Tree Bark-Louse. 659 
ip 
from the scale. This occurs during the last week in July, and 
although no regular or sudden transition takes place, yet during 
the fore part of August the males appear, leaving behind the 
empty larval scales on the leaf, which are easily seen scattered about 
among the females upon both upper and lower sides of the leaf. 
The male louse is very different from the female. During the 
transformation he has acquired wings for the new sphere into 
which he is about to enter, although he still retains the legs and 
antennz, the beak is abortive, its place represented by two round 
spots. The three parts, head, thorax and abdomen are easily 
distinguished. The first males were observed August 13th, 1877, : 
and continued appearing over two weeks. They are very active, 
flying about the leaves with great rapidity. At this time coition 
takes place, and the ovaries become developed in the impreg- 
nated females, which remain on the leaves drawing .sap con- 
tinually during the entire summer. 
The Male-Louse-——Comparatively few of the male-lice have as 
yet*been discovered by entomologists, and it was with pleasure 
that the male of Lecanium acericorticis Fitch was found during 
the summer of 1877. Their existence is for a brief period, since 
they are not found longer 
than three weeks in the 
year; the probable life of 
each individual not being 
its entire existence—a few 
weeks over one year—the 
males acquire wings and fly 
about. That the males are 
necessary for the perpetua- 
tion of the species is doubted by some authors. I made an 
estimate of the number of larval scales on several leaves, and on 
the trees which had suffered a longer time, and found the average 
number to be greater upon a much infested and thus diseased 
tree than upon a healthy and vigorous one upon which the in- 
sects had not been so violently destructive. It often happens 
that a maple-tree will suddenly revive and outgrow the injury 
Fic. 4.—Lecanium acericorticis, male, 
= Of these insects to an extent, even when no attempt has been 
VOL. XII.—NO. X. 45 
