144 
PARASITES OF GIPSY AND BROWN-TAIL MOTHS. 
Anomalon exile Prov. 
Quite commonly reared as a parasite of the tent caterpillar and not 
infrequently as a parasite of the brown-tail moth, apparently attack- 
ing the caterpillars before pupation and probably while they are still 
very }^oung. Its frequency as a parasite of the brown-tail is well 
indicated in Table VI (p. 147), which records the results of the 
summer's rearing work of 1910. 
Theronia fulvescens Cress. 
This is probably, as in the case of the gipsy moth, the most common 
native hymenopterous parasite. No attempt has been made to deter- 
mine whether it is commonly primary or secondary in this connection, 
but it is presumably primary in the majority of instances. 
PlMPLA CONQUISITOR SAY. 
The pupas of the brown-tail moth seem to afford much more suitable 
conditions for the development of the Pimpla larva? than do the pupae 
of the gipsy moth. In consequence this Pimpla is frequently reared 
and is probably about as important as a parasite of the brown-tail 
moth in America as are the European species, Pimpla examinator 
and Pimpla instigator , abroad. 
Pimpla pedalis Cress. 
This species is never so common as Pimpla conquisitor in its asso- 
ciation with the brown-tail moth. It is apparently-identical in habit 
with the more common species, but if results in studies in parasitism 
of other hosts are to be. excepted, it is more apt to occur in forests and 
woodland than in open country. 
DlGLOCHIS OMNIVORA WALK. 
At times Diglochis is a common parasite of the brown-tail moth 
pupse, but in 1910 it was unexpectedly scarce in Massachusetts, 
although it seemed to have been much more common in Maine, judg- 
ing from the small amount of material which has been received from 
that Slate. 
Syntomosphyrum esurus Riley. 
Of irregular occurrence as a parasite of the brown-tail moth, but 
among the more effective of the native species in 1910. It was lirst 
reared in 1906 by Mr. li. L. Webster, while associated with the lab- 
oratory, and not again encountered until 1910, when large numbers 
issued from material collected in certain localities, as will be seen in 
Table VI which shortly follows. 
