1914] Report on Parasites. a7 
continued to spread during the past summer. It has not 
been so abundant in the oldest infested territories as in some 
of the outlying colonies. Collections of more than eleven 
hundred gipsy moth caterpillars made in four towns in central 
Massachusetts show a parasitism by this species of over 40 
per cent, while similar collections in the central infested area 
have indicated an average parasitism of about 5 per cent. It 
is probable that the decrease in parasitism 1n the old infested area, 
as far as this species is concerned, is due to the fact that gipsy 
moth caterpillars are not nearly as abundant as they were 
during the previous year, and also because of the enormous 
numbers of the American tent and forest caterpillars which 
were present in this region and which are also attacked by 
this parasite. : 
Limnerium disparidis and Apanteles species were received 
from Europe for the first time in 1911 and were planted in 
several badly infested gipsy moth colonies. Both species 
were recovered during the summer of 1912, which indicated 
that it is possible for the insects to withstand our cold winters. 
In the case of the latter species, as high as 7 per cent of para- 
sitism of gipsy moth larve was found. The present summer 
the Limnerium was recovered from a single locality where 
the species was liberated in 1911. Although it has evidently 
become established, it has not thus far shown marked ability 
to increase in the gipsy moth infested area in New England. 
Another species of Apanteles, namely A. Jacteicolor, an 
important parasite of the brown-tail moth caterpillars, has 
been recovered in large numbers and has been found to attack 
gipsy moth caterpillars in widely separated regions. This 
species seems to be multiplying more rapidly than any of the 
other Hymenopterous parasites of the gipsy moth. In order 
to colonize this species over as wide an area as possible, an 
arrangement was made with the State Entomologist in New 
Hampshire and the Superintendent of Moth Work in Maine 
to liberate as many colonies as possible along the outskirts 
of the area infested by the brown-tail moth in those states. 
Small collections of gipsy moth larve were made at Melrose, 
and in some cases ten per cent of the larve were killed by this 
species. In several localities in New Hampshire the past 
summer cocoons of this parasite were very abundant, and 
