18 BULLETIN 438, U. S. DEPARTMENT OF AGRICULTURE. 
were found in May, 1914, indicating the probable existence of a 
parasite. In the spring of 1915 the possibility of securing parasites 
was kept in mind. On April 1 three small parasites were found in 
one of the rearing jars, evidently coming from a single cocoon that 
had a small hole in it. The followmg day the sawflies began emerg- 
ing, and continued to do so until April 13. At this time there were 
still over a hundred cocoons in the jars, and these were kept for 
possible parasites. 
On April 24 a small ichneumonid, determined by Mr. S. A. Rohwer, 
of the Bureau of Entomology, as Mesoleius sp., emerged from one of 
the cocoons through quite a large hole that it had made. 
On May 4, 27 specimens of the small parasite previously referred 
to were found in one of the rearing jars, having come from four 
different cocoons, and in another jar 15 specimens of the same species 
had emerged from three cocoons, or an average of 6 parasites for 
each cocoon. These parasites, evidently chalcidids, have not been 
determined. 
On May 19 a single larger parasite was found, which, upon being 
submitted to Mr. S. A. Rohwer, proved to be a chrysidid, probably 
Cleptes provanchert Aaron. 
Thus it appears that of 308 cocoons, only 10, or a little over 3 
per cent, were parasitized. The ravages of the sawfly would not be 
diminished to any appreciable extent by this degree of parasitism, 
though there may be years when these parasites are much more 
numerous. It is imteresting to note that practically all of these 
parasites came out considerably later than the adult sawflies, and 
at about the time when the largest number of sawfly larve were 
full grown. This indicates that the parasites oviposit on the larve, 
which is probably the case, as it is difficult to understand how they 
could reach the larvee after the latter had spun their cocoons in the 
soil. Since there is but one brood of the host, there would be only a 
single brood of the parasites if peculiar to this host. 
In California larvee of coccinellid beetles in rare instances have 
been observed to prey on the larve of the pear sawfly. Before the 
first of May coccinellid larve are comparatively scarce, and so it is 
unlikely that they will ever prove a check upon the pear sawfly. 
REMEDIAL MEASURES. 
The pear leaf-worm is easily controlled when in the larval stage. 
A poison spray, such as arsenate of lead, if properly applied, is 
highly effective (Pl. II, fig. 1), because of the habit possessed by this 
insect of passing the whole period of this stage of its life upon the same 
leaf, unless forced to move away by interference, accident, or scarcity of 
food, mainly due to the location of several larve on one leaf and the 
fact that they consume it before they attain the stage of pupation. 
