810 
[Assembly 
color, adhering to the bark on the under sides of the limbs, par¬ 
ticularly of young trees which are growing thriftily. These 
scales are the relics of the dead females covering and protecting 
their young. Some are of a darker color than others, and smaller 
ones occur which are of a dull yellow hue. These scales are not 
freckled with paler spots like many of our species of bark-lice ; 
their surface frequently presents shallow indentations as though 
it had been slightly pressed upon in places with the head of a 
|~—1 pin, and the outer margin is wrinkled, as shown in 
yt&fo accompanying figure, and is sometimes marked with 
l| ] faint black bands. If one of these scales is removed 
a round white spot the size of the scale remains upon 
the bark, appearing as though made with chalk. Upon the un¬ 
derside of one small twig, in a distance of nine inches, thirteen 
of these scales occurred and five white spots where other scales 
had been rubbed off. 
At the time when I noticed these scales the young lice under 
them were active and so minute that they appeared to the eye 
like particles of dust. I conveyed a tw r ig to my residence and 
bound it to a thrifty limb of a young apple tree,, to ascertain 
whether they could subsist upon this tree; but they all perished, 
not one of them leaving the pear twig, that I could discover. The 
following May the chalk-like spots where the scales had been 
fixed upon the twig were still distinct, the storms and frosts of 
autumn and winter having scarcely dimmed them in the least. 
Beneath the scales the young lice are interspersed through a 
mass of white cotton-like matter. This subsequently increases in 
volume and protrudes from under one end of the scale, elevating 
F it from the bark, as shown in the annexed cut. The 
young lice now crawl out from among this matter and 
diffuse themselves over the smooth bark, appearing to 
the eye like minute whitish specks or fine dots. When 
magnified they are found to be of an oval form, somewhat flat¬ 
tened, about the hundredth part of an inch in length, and two- 
thirds as broad as they are long. They are of a dull white color, 
with six legs and two short antennae of a hyaline-white appear¬ 
ance. The antennae are thread-like or of equal diameter through 
