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in 16 inSi vi dual collections averaged. 40 percent or higher parasitization by this 
species and the maximum parasitization of 71,1 was observed. It was reared 
from 83 of the 99 individual collections made and is known to he present over 
an area of approximately 1,700 square miles in southeastern Massachusetts* It 
was recovered east of the Canal on Cape Cod as far out as the town of Mashpee, 
Its spread westward has been comparatively slow* M. gifuensis . released in 
1939 and 1940 at Atlantic, Monmouth County, N. Y., was well established at this 
point, and considerable dispersion was indicated by its recovery 2 miles from 
the point of release, 
Eulophus viridulus Thoms . — This gregarious ectophagous chalcid parar- 
site was first released in the Lake States area in 1931 but no recovery was made 
until 1938. Since then surveys' have shown that, although the parasite has 
spread, it has not notably increased in abundance at any point. Luring the 1939 
•season it had been found that E. viridulus had dispersed a considerable distance 
in the counties south of Toledo, Ohio. In order to check further on this spread, 
observations were made in six counties not examined in 1939. These counties 
were Allen, Auglaize, H a rdin, Logan, Seneca* and Sandusky. Only one observation 
per township was made and only a few townships in some of the counties were 
included in the survey. The parasite,, however, was recovered in all counties 
under observation and it was indicated that at some points the species may be 
present in encouraging numbers. One colony was found over 50 miles from the 
nearest release point. The farthest limits of dispersion we re not defined by 
this survey and;' because of the limited observations, no dispersion direction 
tendency can be drawn from the data. "No recovery of this species was made in 
the eastern area. 
Chelonus annulipes Wesm . '■ — This braconid, released in 1938 in the 
multiple-generation area west of Toledo, Ohio,, although showing strong establish* 
ment for 2 years, failed to appear in 'the 1940 collections from the Lake States 
area. In southeastern Massachusetts C. ‘annulipes was not more abundant in 1940 
than it was in 1937 and 1938 and less numerous than it was in 1939. The area 
from which It was taken remains rather limited. Parasitization of the borer 
by this braconid was only 0.8 percent and it was reared from only 7 of the 99 
host collections from this locality; however, parasitization was over 10 percent 
in 4 of the 7 collections from which the parasite was reared. Since the parar- 
site was present in rather large numbers in the fields from which it was taken 
and since these fields were more or less scattered and no individuals were 
reared from borer collections from intervening fields, it is indicated that 
0. annulipes is very selective in its choice of environment. This characteris- 
tic is further emphasized by the recovery of Ghelonus at only 1 point in the 
Hartford, Conn*, 'area, where a number of closely spaced releases had been made 
in 1939 and where the parasite had been recovered in 5 collections taken in the 
fall of that year. 
Native parasites . — The following native parasites appeared in small 
numbers in the 1940 collections: Aplomya caesar Aid. from the Lake States col- 
lections; and Carcelia ochracea V.d.W., Macro centrus robustus Mues., Bassus 
agi li s Cress,, and Labro ryciius pri smati cus Nort. from the Eastern States. 
