‘ 
‘ 
oe. «INSECTS INJURIOUS .TO THE ELM. 61 
The eggs of the tree cricket begin to develop as soon as they are laid 
in the early autumn, and the embryo partially develops, so that the 
rudimentary limbs may 
be seen, as well as the 
mouthparts; the insect “e 
completes its develop- Fic. 21.—Female tree-cricket, natural 
ment in the early part of size.—A fter Harris. 
the following summer, appearing early in August. 
AFFECTING THE LEAVES. 
Fic. 20.—Male tree- 8. THE CANKER WORM. 
cricket.—A fter Har- : 
ris. 
Anisopteryx vernata Peck. 
Order LEPIDOPTERA; family PHALEZNIDZ. 
Very injurious to the elm in the Eastern States, stripping the trees; a dark-striped 
measuring worm varying in color to pale green, transforming from the middle to the last 
of June in the earth to a pupa, some appearing in the autumn but most abundantly in 
March; the female grub-like, the male winged. 
Originally confined, as an injurious insect, to New England, it is now 
destructive in the Western States (Illinois and Missouri), and must 
originally have occurred all over the United States east of the Missis- 
sippi, as I have received it from Texas. 
r 
ei 
ae 
(i) 
fi 
ib 
¥y1c. 22.—Canker worm; ), egg; ¢, Fic. 23.—a, female canker-worm moth; b, male; ¢, 
side; d, back of asegment.—A fter antenn joints of female; d, one of female abdomi- 
Riley. inal segments; e, ovipositor.—After Riley. 
About the Ist of May, at the time when the leaves of the apple are 
unfolding, the young canker worms break through the eggs, which have 
been laid earlier in the season, in March and April, in patches on the 
bark of the trunk and limbs. They may be soon found clustering on 
the terminal buds and partly unfolded leaves, and are then about a line 
jn length, and not much thicker than a bit of thick thread. Fortunately, 
owing to the want of wings, the female is exceedingly sedentary, and 
year after yearthe apple and elm trees of particular orchards and towns 
are defoliated and turned brown, while adjoining orchards and towns 
searcely suffer. By the 20th of June, in Essex County, Massachusetts, 
- the orchards or shades elms infested by them look as if a fire had run 
through them. At that date the worms are fully fed, and they then 
descend to the ground, letting themselves down by a silken thread. At 
this time I have destroyed thousands by jarring the tree and collecting 
those which fall down. I have watched old and young robius busily 
