April, ’20] 
FERNALD: ORIENTAL MOTH 
211 
southwest from the probable center of infestation than in any other 
direction, and the longest distances in the territory are almost two 
miles in a northeast, southwest direction, by a mile and a half at right 
angles to this. 
During the winter of 1916-17, through the kindness of Mr. L. H. 
Taylor, one of the deputy state nursery inspectors, this territory was 
scouted, with a view of learning how far the Oriental moth had spread 
in ten years. It was found that the territory then occupied by the 
insect, though still very irregular in outline, was nearly four miles in 
* 
length, and nearly three miles in width at its widest point, and with 
an average width of nearly two miles. 
The insect has now reached the ocean on the east and has extended 
its distribution farthest to the south and southeast from its center, 
though also somewhat to the north. It has hardly spread at all to the 
west, for some reason not at present apparent. 
For a number of years the writer tried without success to obtain a 
parasite of the Oriental moth, which had been recorded as attacking it 
in China. Finally, through the kind assistance of M. l’Abbe J. de 
Joannis of Paris, the cooperation of M. Gaudissart of Tientsin, 
China, was obtained, and in 1917 shipments of parasitized cocoons of 
the Oriental moth were received, followed by others up to the present 
time. These parasites were bred out in the laboratory of the Massa¬ 
chusetts Agricultural College and liberated in the infested territory. 
The small number of parasites received in the earlier shipments made 
the recovery of the insect doubtful even if it established itself, but 
later consignments in 1918 increased the chances of recovery, and a 
collection of Oriental moth cocoons made in the infested area in March, 
1919, showed that about 6 per cent had been parasitized by the im¬ 
ported enemy. This is an encouraging showing. 
The parasite is a Chrysid, Chrysis shanghaiensis Walk., a very 
representative member of the family, about half an inch long when 
adult. Apparently it does not attack the larvae but is a pupal parasite, 
and herein has been the chief difficulty in colonizing it thus far, for the 
adult tends to emerge while its host is a larva about half-grown, and 
by the time pupation occurs, the weather is often so cold that the 
parasite becomes sluggish. Attempts will be made in 1920 to hold 
back the emergence of the parasites, by cold storage, until near the 
pupation time of the host, and then, if reasonably warm weather comes, 
the chances of a larger amount of parasitism should be greatly in¬ 
creased. Further studies on the life and habits of the Chrysis are now 
being carried on. 
So far as the writer has been able to learn, this is the only case known 
where a Chrysis is parasitic on a lepidopteron, but no evidence has 
