70 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 17 
mately 75,000,000 parasites have been colonized over much of the in¬ 
fested area. 
The records of parasitism which have been obtained at the Gipsy 
Moth Laboratory are very promising and show that a great deal of 
benefit is now being derived from these introductions and the coloni¬ 
zation work, yet the combined good of these benefactors has not been 
great enough to trust in them alone for the Biological Control of the 
Gipsy Moth and Brown-tail Moth. Because of these facts and also 
because many of the above mentioned 46 introduced insects were never 
colonized in sufficient numbers in this country to expect their establish¬ 
ment, it was decided in 1921 to attempt again to introduce and establish 
in this country more species of foreign parasites of the Gipsy Moth and 
the Brown-Tail Moth. 
During the fall of 1921 Mr. A. F. Burgess, Entomologist in Charge of 
Gispy Moth and Brown-Tail Moth Investigations, made arrangements 
to have more foreign work done and during the latter part of January 
1922 a consultation was held with Dr. Howard, after which Dr. J. N. 
Summers was sent to Japan and the senior author of this paper to 
Europe. 
In Europe: France, Spain, Italy and Germany were visited and con¬ 
ferences were held with many of the leading entomologists of these 
cotmtries. Most of these entomologists knew of no gipsy moth in¬ 
festations in their country that year, and long hours of search by the 
writer failed to locate suitable infestations for parasite importation 
work. 
An idea of the scarcity of this insect over much of Europe in 1922 is 
shown by the fact that only one gipsy moth egg cluster was found in 
two weeks search in the northern part of France, and a few days scouting 
in an area about 150 miles north of the south coast of France. A re¬ 
markable feature is that much of this scouting was done in areas where 
the growth was favorable for the insect. A few very light infestations 
were found along the southern coast of France and in Italy and Sicily. 
In Spain several gipsy moth infestations were present. One in the 
Royal Forest near Madrid and another about 150 miles south of Madrid 
near Villanueva de Cordoba were reported more severe than the others. 
Through the kindness of Dr. Manuel Aullo, Director of the Service of 
Study and Extinction of Forest Plagues of Spain, the infestation in the 
Royal Forest was visited and found to be a severe one. It was surpris¬ 
ing that the infestation was of several years standing and yet no dead 
or dying trees were observed. 
