February, '24] 
CROSSMAN & WEBBER: GIPSY MOTH PARASITES 
67 
The gipsy moth problem cannot be evaded. Spread and individual 
control or lack of control, both extremely costly, the latter possibly 
ruinous, are inevitable unless the state and nation continue the work 
already started. There is no reasonable hope of a materially shorter 
barrier zone. Those familiar with the situation realize that it must be 
either the proposed line or simply general repressive work over a con¬ 
stantly increasing area accompanied by mounting costs and unsatis¬ 
factory control in our large and valuable forest areas. A failure on the 
part of the Federal Government to assume early a reasonable share of 
the expense of protecting the remainder of the country from this insect 
may force the abandonment of one of the most important projects in 
economic entomology. 
President A. G. Ruggles: A paper will now be presented by 
S. S. Crossman and R. T. Webber. It will be read by Mr. Crossman. 
RECENT EUROPEAN INVESTIGATIONS OF PARASITES OF 
THE GIPSY MOTH, PORTHETRIA DISPAR L., AND THE 
BROWN-TAIL MOTH, EUPROCTIS CHRYSORRHOEA L. 
By S. S. Crossman, Entomologist, Bureau of Entomology, and R. T. Webber, 
Assistant Entomologist, Bureau of Entomology 
Abstract 
The paper pertains to recent investigations in Europe of the Gipsy Moth and 
Brown-tail moth and their natural enemies. Mention is made of the previous work 
which resulted in the introduction of 36 species of Tachinid and Hymenopterous 
parasites and 10 species of beneficial Coleoptera. Of the 46 species named, 15 have 
actually been established. 
In several instances the original numbers imported were so few that breeding had 
to be done before enough individuals could be obtained for colonization and in a few 
cases a sufficient number, were not received to make breeding for liberation possible. 
As the species have become established, the material for new parasite colonies has 
been obtained by breeding it at the laboratory and the different species have been 
colonized further out from Melrose until about 75,000,000 individuals have been 
liberated over much of the moth infested area. Several of the parasites are now 
present in many of the towns on the border of the infestation and one species, C. 
concinnata, is being recovered from native hosts 60 miles beyond the quarantine line. 
The records of parasitism which are being obtained at the Gipsy Moth Laboratory 
are excellent and show that a great deal of benefit is being derived from these intro¬ 
ductions, yet the combined good has not been great enough to trust in them alone 
for the Biological Control of these two injurious insects. 
During the spring and summer of 1922 the senior author investigated the Gipsy 
Moth and Brown-tail Moth situation in several countries in Europe and in the 
spring of 1923 the writers visited France, Spain, Italy, Germany, Austria, Hungary, 
