COMMON APPLE-TREE. 319 
worms of different ages, and even among those of the same age and size. When 
very young, they have two minute warts on the top of the last rings, and they 
are then generally of a blackish or dusky-brown colour, with a yellowish stripe 
on each side of the body ; there are two whitish bands across the head ; and the 
belly is whitish. When fully grown, these individuals become ash-coloured on 
the back, and black on the sides, below which, the pale, yellowish line remains. 
Some are found of a dull greenish-yellow, and others of a clay-colour, with slen- 
der interrupted blackish lines on the sides, and small spots of the same colour on 
the back. The head and feet partake of the general colour of the body ; the belly 
is paler. When not eating, they remain stretched out at full length, and resting 
on their fore and hind legs, beneath the leaves. When fully grown and well fed, 
they measure nearly or quite an inch in length. They cease feeding when about 
four weeks old, at which time they begin to quit the trees. Some creep down 
by the trunks, but great numbers let themselves down by their slender threads 
from the branches, their instincts prompting them to get to the ground by the 
easiest and most direct course possible. After reaching the ground, they imme- 
diately burrow into the earth, to the depth of two to six inches, unless prevented 
by weakness, or by the hardness of the soil. In the latter case, they die, or 
undergo their transformations on the surface. In the former, they make little 
cavities or cells in the ground, by turning round repeatedly, and fastening the 
loose grains of earth about them with a few silken threads; and, within twenty- 
four hours afterwards, they are changed into chrysalides, and in due time, emerge 
from these retreats in their perfect form. In order to protect the trees from the 
ravages of the canker-worm, the only thing that would seem necessary would be 
to prevent the wingless females from ascending the trunks to deposit their eggs. 
The expedients usually resorted to for this purpose, are, to fit a close collar of 
lead, tin, wood, or other materials, around the trunks of the trees, or a circular 
trough filled with oil. The application of belts of tar, liquid Indian rubber, and 
other viscid substances, to the bodies of the trees have been employed with 
partial success. 
The apple-tree is also infested by the larvae of the white-marked orgia, or 
tussock-moth {Orgia leucostigma, Harris.) These small, slender caterpillars 
are of a bright-yellow colour, and are sparingly clothed with long and fine yellow 
hairs on the sides of their bodies. The females, in the adult state, though seem- 
ingly wingless, have two little scales or stinted wings, while the males have 
large ashen-gray wings, the upper pair of which are crossed by dark wavy 
bands, with a small black spot near the tip, and a minute white crescent near 
the outer hind angle. The body of the male is small and slender, with a row of 
little tufts along the back, and the wings expand one inch and three eighths. The 
females are of a lighter gray than the males, and their bodies are much thicker, 
and are of an oblong-oval shape. Different broods of these insects appear at 
various times in the course of the summer, but the greater number come to 
maturity and lay their eggs in the latter part of August and the beginning of 
September, which are not hatched before the following spring. It is stated by 
the late Mr. B. H. Ives, of Salem, Massachusetts, in vol. i., p. 52, of Hovey's " Gar- 
dener's Magazine," that on passing through an apple orchard in February, he 
" perceived nearly all the trees speckled with occasional dead leaves, adhering so 
firmly to the branches as to require considerable force to dislodge them. Each 
leaf covered a small patch of from one to two hundred eggs, united together, as 
well as the leaf, by a gummy and silken fibre, peculiar to the moth." In the 
March following, he visited the same orchard, and as an experiment, cleared 
three trees, from which he took twenty-one bunches of eggs. The remainder of 
the trees he left untouched until the 10th of May, when he found the 1 caterpillars 
were hatched from the egg, and had commenced their slow, but sure work ot 
