PARASITES OF GIPSY-MOTH PUP. 255 
earth, and effectually demonstrated the superiority of this method 
over that involving the use of the large out-of-door cages. The fol- 
lowing spring the work was undertaken upon a considerably larger 
scale, and along still more specially developed lines. From the 
hibernated parent stock, and from newly imported beetles, he reared 
large numbers of larve, a part of which were allowed to complete 
their transformations in confinement, while others were colonized 
directly in the open when about half grown. These larval colonies 
promised to be successful, and accordingly the work of rearing the 
larve and distributing them throughout the gipsy-moth-infested area 
in eastern Massachusetts, with an occasional incursion into other 
parts of the infested area, was continued throughout 1909 and 1910. 
Meanwhile, beginning in the late summer of 1907 and continuing 
uninterruptedly until the close of the season of 1910, Calosoma has 
been steadily gaining in the confidence of those who have watched 
its progress. Its larve were first recovered from the field at just 
about the time when Mr. Burgess first took over the beetle work, and 
its ability to complete its seasonal cycle in America unassisted was 
thus indicated. The large colony was also proved to be unnecessary. 
Its progress in the field was slow at first, even in the instance of 
the large adult colony founded in 1907 before it was known to have 
become established. In 1908 its larve were found in abundance in 
the center of this colony, but not to any great distance away from 
the point where the beetles had first been liberated. In 1909 the 
spread was more rapid, but at the same time restricted in comparison 
with that which became evident in 1910. As will be seen by reference 
to the accompanying map (Pl. XXIV) which has been prepared by 
Mr. Burgess from the results of the scouting work of three years, its 
apparent or discernible dispersion has been at a rapidly increasing 
rate each year in the instance of colonies which, like these, chanced 
to be so happily located as to allow for unrestricted and uninter- 
rupted increase from the start. 
At the present time there is every prospect that a continued rapid 
increase for a few years more will result in an abundance of the 
beetles sufficient to render very efficient aid in the fight against the 
moth. It is not expected that they will be of very much assistance 
in localities in which the moth is reduced to such numbers as to make 
control through parasites such as Compsilura and others of its char- 
acter possible, but it is expected that whenever the moth breaks out 
of bounds, and increases to such abundance as to afford the beetles 
and their larve an unlimited food supply, first migration and later 
rapid multiplication of the beetle will result. In this respect the 
rdle played by Calosoma is similar to that which is rather confidently 
expected of Blepharipa. 
