AMERICAN ECONOMIC ENTOMOLOGY 219 



Africa, in Europe at any rate it is only very occasionally that 

 it appears in numbers sufficient to effect any serious harm. 

 Not so in America, where climatic conditions conduce to its 

 multiplying in an extraordinary degree. The introduction of 

 the species was due to an astronomer residing at Medford, who 

 was making experiments on silk-spinning caterpillars, and in 

 1869 imported some of those of the gipsy-moth. These were 

 kept on a shrub under netting, but during a gale the net was 

 torn and the full-grown moths escaped. Although notice was 

 given of the escape, the insect was not noticed in the district 

 for several years, although by 1889 it occurred in such numbers 

 as to constitute a real pest. 



Medford at first endeavoured to fight the invader alone, but 

 in 1890 the State of Massachusetts furnished financial assistance 

 for the same purpose. This was continued till 1899, when 

 further funds were refused ; this state of affairs continuing until 

 1906, when active efforts were resumed by the State. The 

 interruption of the work of repression and hoped-for extermina- 

 tion may be described as almost disastrous. 



" In 1899," it is stated in a recent Bulletin, "the State Board 

 of Agriculture had the problem well in hand, and at that time it 

 seemed very probable to skilled practical entomologists who 

 looked into the matter that even extermination was possible in 

 the course of a comparatively short time. But the five years' 

 interruption of the work caused the spread of the insect from a 

 restricted territory of 359 square miles throughout an extended 

 range of 2,224 square miles." 



For a long time the National Government refused to partici- 

 pate in the work of checking the advance, but Congress has 

 recently voted 82,500 dollars for the purpose of checking the 

 further spread of the gipsy and the brown-tailed moth. 



As regards the modus operandi of this, it became evident after 

 careful investigation that the moth spreads itself by means of 

 vehicles proceeding from the infected territory along the main 

 roads. Accordingly, it was deemed advisable to take effectual 

 methods for keeping these roads in the most thickly infested 

 districts as scrupulously clean as possible. This has been done, 

 but with what results the future must show. As regards the 

 isolated colonies of the moth, attempts have been made to stamp 

 them out of existence, but we must await the end of this summer 

 to see whether these have been really effectual. 



