26 



The gypsy moth was discovered here for the first time during the 

 winter of 1909-10, by finding egg clusters. Several of these clusters, 

 unfortunately, had been already killed with creosote before my first 

 visit, but there were present, according to Mr. Souther's and my esti- 

 mation, about 25 clusters. Whether there was any disease among the 

 caterpillars of the previous year could not be ascertained, but it is 

 highly improbable, considering the youth of the colony and the large 

 size of the clusters. 



On June 14, 1910, the local superintendent sent me word that 

 wilt had made its appearance among the caterpillars which he had 

 collected and fed according to instructions. I therefore went to North 

 Carver on June 16, and found that in Mr. Atwood's colony about 

 3 per cent, of the caterpillars had already died of Flacherie. Most 

 of those still living were very sick. He therefore had developed the 

 wilt artificially after a feeding of about fourteen days. 



This same day, with the assistance of the local superintendent, a 

 part of the breeding material was exposed on the western side of the 

 selected place. The bag containing the material was fastened about 

 8 feet from the ground, between young oak trees. Most of the cater- 

 pillars of this locality had just passed the third molt. 



On Oct. 7, 1910, an extended search was made by the local super- 

 intendent and myself, but only 4 fresh clusters could be found. The 

 microscopic examination of .these 4 clusters resulted as follows : 



Unfertilized eggs, . 

 Eggs with dead embryos, 

 Eggs apparently alive, . 



Total, 



Cluster 1. 



2j \ = 6.03 per cent., or about 6 per cent. 

 405 =93.97 per cent., or about 94 per cent. 



431 eggs. 



Unfertilized eggs, . . 

 Eggs with dead embryos, 

 Eggs apparently alive, . 



Total, 



jg 

 375 



Cluster 2. 

 \ = 5.38 per cent., or about 5.5 per cent. 



94.62 per cent., or about 94.5 per cent. 



Unfertilized eggs, . 

 Eggs with dead embryos, 

 Eggs apparently alive, . 



Cluster 3. 



4.65 per cent., or about 4.5 per cent. 

 205 =95.35 per cent., or about 95.5 per cent. 



Total, 



215 eggs. 



