EGG PARASITES OF THE GIPSY MOTH. 173 
The 90,000 parasitized eggs were divided into five lots and placed in 
the field at the proper time in localities where an abundance of eggs 
was certain. 
The parasites hatched in due course and were found attacking the 
ego masses in a businesslike manner that was quite encouraging, 
but only within a very short distance of the center of the colony. 
The species thus spreads slowly. 
Fig. 16.—Diagram showing two years’ dispersion of Anastatus bifasciatus from colony center. Each 
concentric circle represents a distance of 50 feet from the smaller or larger circle next it. A indicates 
parasitism of gipsy-moth egg-masses hy Anaséatus bifasciatus and O indicates absence of parasitism 
by Anastatus. The figures give percentages of parasitism. ( Original.) 
The accompanying diagram (fig. 16), which has been prepared by 
Mr. Wooldridge largely from the results of his own work, together 
with Table VIII, will serve as well as words to tell the story of the 
dispersion of this parasite in one of the 1909 colonies, and results of 
similar studies in various other colonies are substantially the same. 
