96 NEW YORK STATE MUSEUM 
that there had been no spraying since 1900, at which time an effort 
was made to destroy forest tent caterpillars with a contact insecti- 
cide. The work of this apple enemy is easily recognized by its 
trumpet-shaped mine which commences as a glistening spot where 
the egg was laid, continues for a short distance as a narrow line, 
gradually expanding and then suddenly widens into an irregular 
expanded portion. The mine is on the upper side of the leaf and 
when old, turns brown and is scarcely seen from the under surface. 
It is inhabited by a greenish, footless, active caterpillar. The upper 
and lower walls of the mine are densely lined with silvery white 
silk forming a winter retreat for the larva, which latter trans- 
forms in the spring to the pupa at one end of the mine and in 
a short time forces its way partly out through the upper surface of 
the mine and then the moth emerges. 
This species appears on’ the foliage so late in the season that 
comparatively little injury is caused and, as a rule, remedial meas- 
ures are unnecessary. One method of controlling this insect in 
case of necessity is to burn the fallen leaves which, as stated above, 
contain larvae or pupae, and thus reduce the number of insects 
another season. Spraying the foliage in summer with 10 to 15 
per cent kerosene emulsion has also proved of value in destroying 
the larvae in their mines. 
Palmer worm (Ypsolophus ligulellus Hub.). The 
small, pale green or yellowish green, active, striped caterpillars of 
this species aroused much interest in 1900 because of their ex- 
treme abundance in orchards in Genesee county. This insect ordi- 
narily escapes attention and, prior to the above mentioned out- 
break, had scarcely been noticed subsequent to 1853. Palmer worm 
larvae were rather generally present the latter part of June 1912 in 
orchards in and about Byron and were found in small numbers 
upon apple trees at Nassau. Apples with freshly eaten irregular 
holes were noted near caterpillars, and one was found in a posi- 
tion which suggested that it had just been feeding upon the fruit. 
The full-grown caterpillar is about half an inch long and is then 
usually of a pale green or yellowish green color with a dusky, sub- 
dorsal line. The head may be either yellowish or blackish. Though 
there is considerable variation in color the larva is not difficult to 
recognize, since it is very active and drops much in the same 
manner as does the canker worm when disturbed. Leaves partly 
skeletonized by this insect soon turn brown, curl and present an 
unsightly, ragged appearance. It is interesting to note that the 
