75 



remedy one day may l>e wrong- the next day, just as we are able to 

 unravel nature's seerets and interpret them for our own good. 



Since the above was read the writer has tested a lot of twigs from 

 the Charles County orchard and has l)red numerous specimens of A 

 fuscipeimis, thus proving that a parasite is thoroughly established 

 there. 



THE BROWN-TAIL MOTH IN MASSACHUSETTS. 



By A. H. KiRKLAND, Maiden, iLasa. 



It is seldom possible to record with accuracy from year to year the 

 spread of an introduced insect pest. The average working entomolo- 

 gist has at his disposal neither the time nor the funds necessary to 

 follow the spreading- swarms afield. It therefore follows that in such 

 cases our records of insect dissemination have been built up by col- 

 lecting- and combining data in the possession of entomologists and lay- 

 men. This method is the only practicable one in the case of those 

 insects whose spread is dependent upon the agency of commerce. 

 Such cases do not possess the interest, at least from a biological stand- 

 point, of those where natural means of distribution predominate. 



The writer thinks the present a good time to record a few" notes on 

 the natural spread of the imported brown-tail moth in Massachusetts, 

 particularly since the abandonment of work against this insect will 

 prevent the accurate collection of further data. 



With this insect in Massachusetts a unique condition has made it 

 possible to follow its increasing distribution with more than ordinary 

 accuracy. When the insect w^as first noticed in the State, in 1897, the 

 work of combating it was placed in charge of the board of agriculture. 



At that time the board had employed in the gypsy-moth work about 

 300 men, who from practical experience were fairly close observers 

 of insect life. While it should not be understood that these men 

 were experts, yet they were capable of recognizing the gypsy moth 

 in all stages, and soon gained an equally accurate knowledge of the 

 brown-tail moth, particularly after having experienced the intense 

 nettling caused by the caterpillars. The duties of selected mem- 

 bers of this working force included a search each fall to determine 

 the extent of the spread of the brown-tail moth outside the area occu- 

 pied the previous spring. With such employees the chance for erro- 

 neous determinations of the moth was small. The writer might add 

 that he was able to verify the determinations in all doubtful cases. 



In the paper read by Prof. C. H. Fernald before this body in 1898 

 a description was given of the high gale which, occurring in the Hying 

 season of 1897, disseminated the moth for many miles to the north- 

 ward. This northerly spread is even more apparent at the present 



