APANTELES MELANOSCELUS GIPSY-MOTH PARASITE. 25 
same summer some interesting data were obtained from a medium- 
sized oak tree near the Gipsy Moth Laboratory at Melrose Highlands. 
This tree had many gipsy-moth egg clusters on it which had not been 
creosoted during the winter, so that on this particular tree there 
was a much heavier infestation of gipsy-moth larvse than on any of 
the other trees in the vicinity. As the summer progressed, cocoons 
of A. melanoscelus began to appear in surprisingly large numbers. 
When most of the first-generation maggots had issued and spun their 
cocoons, the underside of nearly every crotch on the tree was covered 
with Apanteles cocoons (PI. II, C). 
There were 5,140 first-generation cocoons collected from this tree. 
A few cocoons could not be reached and some had blown away before 
the collection was made. Later in the season 511 second-generation 
cocoons were taken from the tree, making a total of 5,651 cocoons of 
A. melanoscelus removed from this tree. Although heavily infested 
the foliage on the tree was not damaged much by the feeding of the 
gipsy moth larvse and very few gipsy-moth pupa? were found on the 
tree. These data are not given as a sample of the condition of the 
trees in Melrose Highlands in 1916, but the figures are interesting 
and show what happens under some conditions. Occasionally large 
oak trees have been seen in other towns on which it was estimated 
there were from 6,000 to 10,000 cocoons. 
In 1918 this parasite was found in large numbers over an area of 
several acres of woodland in Cohasset. In 1919 and 1920 it was 
found abundantly in small areas in Hampton, N". H., and in the 
following towns in Massachusetts: Beverly, Quincy, Weymouth, 
Cohasset, Scituate, Marshfield, and West Boylston. 
CONCLUSION. 
Apanteles melanoscelus has been present in New England since 
1911 and is now firmly established. It is spreading rapidly from 
the colonies which have been liberated and is increasing in spite of 
its being heavily parasitized by secondaries. 
The fact that A. melanoscelus is able to complete its life cycle on 
several native insects adds considerably to its value as an introduced 
parasite and makes its permanent establishment more certain than 
if the gipsy moth were its only host. 
This parasite has two generations each year on the gipsy moth 
and is very abundant in many small areas. It gives promise of 
becoming one of the most valuable of the imported parasites. 
