744 NEW YORK STATE MUSEUM 
are enough individuals in one gall to give an empty one a very 
characteristic appearance on account of the whitish, projecting 
pupal cases. A gall is represented at pl. 4, fig. 1. 
Adult flies were obtained from May 22 onward, from material 
received on the 10th, and on the 31st a parasite was bred. This 
was kindly identified by Dr Ashmead of the United States 
national museum as Tridymus salicis Nees, a species 
recorded for the first time in America. Tridymus metal- 
licus Ashm. was bred in small numbers from galls received in 
the spring of 1902 and Polygonotus salicicola Ashm. 
was reared in numbers. This abundance of parasites leads us to 
hope that natural agents will 
soon control this pest. Twigs 
received June 3, 1901, directly 
from the willow plantation 
i 
a 
Nae 
Pema iid NIN 
had disclosed some flies, 
showing that the period of 
emergence extends. over a 
number of days. Mr Peck 
further states that Mr Wil- 
son has been in the habit of 
opening cases of imported 
stock near the block of in- 
fested willows; so it would 
be comparatively easy for 
SS 
them to become infested. 
= 
SS 
= 
<== 
Ss 
a 
= 
Carpenter moth, Prion- 
<a 
soos 
= 
—— 
= 
== 
=. 
Ooxystus ro biniae Pease 
== 
his is a serious enemy to 
Fic. 17 Work of carpenter moth caterpillars, 
Pupal case nnd adult (orletnal) maple, oak and ash trees in 
certain sections of New York state. Its destructive work 
at Ogdensburg was brought to my attention by Miss Mary 
B. Sherman of that place, and through her some inter- 
esting examples of the borers’ work in sugar mapletrees 
were secured. One third of a section of a tree about 15 inches 
in diameter was fairly riddled with the large burrows of 
the caterpillar of this insect. It was so abundant as to 
