4 i4 POPULAR SCIENCE MONTHLY 



into the United States. At the same time the state of Massachusetts 

 appropriated $10,000 a year for three years for the same end. A 

 special superintendent, Mr. Kirkland, with a staff of agents and as- 

 sistants, was charged to preside over the execution of the work in 

 America, and Mr. Howard, during the three years 1905, 1906 and 

 1907, was sent on a mission to Europe to seek for the parasites of the 

 two species, visiting France, England, Italy, Germany, Austria, Hun- 

 gary and Eussia. He interested in his enterprise all of the official 

 entomological bureaus, as well as the principal specialists, who promised 

 him their help and active cooperation. 



It is by hundreds of thousands that the nests of the brown-tail moth 

 have been sent to Boston for two winters. It is in innumerable 

 quantities that, during the months of June and July, caterpillars and 

 chrysalids of the two species have been sent to both destinations. All 

 these insects, upon their arrival in Boston, where they have been 

 received by Mr. Kirkland, are sent to a laboratory specially constructed 

 for this work. It is in the suburbs of a small village named Saugus, 

 in a house which is constructed in the midst of woods infested by the 

 caterpillars of the two species. Aside from the rooms devoted to 

 research and rearing work, this house contains the local or resident 

 assistant, who has charge of the work, and also the specialists who are 

 sent by the bureau from Washington, at the time when the insects are 

 appearing. The insects are reared in boxes constructed for that 

 purpose, and somewhat like those employed by the State Board of 

 Horticulture of California. To avoid the issuing of hyperparasites 

 or of suspected species not existing in America, and accidentally mixed 

 with the sendings, the cages are kept in closed rooms with double doors. 

 They are arranged side by side in several longitudinal rows, and so 

 abundantly that it is difficult to walk between them. When issued, the 

 parasites are generally not set at once at liberty, but are allowed to 

 breed in large outside cages. 



To what practical results will these experiments conduct us ? It is 

 difficult to answer this question in a decisive way. The experiments 

 have been in any case carried on under conditions most perfectly con- 

 stituted to assure the success of the enterprise, and it was impossible to 

 confide their execution to a savant of greater authority than the 

 eminent director of the Bureau of Entomology, at Washington. Hav- 

 ing a great number of parasites imported, an abundance of food which 

 they find at their disposition, and a climate which they will encounter 

 analogous to that of Europe, it does not appear doubtful that many 

 species will acclimatize themselves, and as soon as acclimatized, they 

 can not fail to strongly influence the balance of nature to the prejudice 

 of the destructive species. 



The time necessary for this movement of the see-saw may be long, 



