NARRATIVE OF PROGRESS OF WORK. 55 



and the brown-tail moth in so far as their natural checks are con- 

 cerned. It was the aim to establish, not one or half a dozen of its 

 natural enemies, but all of them, aiming at the same time to avoid 

 the introduction of hyperparasites — that is, those species that prey 

 upon the true parasites of the injurious forms — thus, if possible, bring- 

 ing about an even more favorable situation for the primary parasites 

 in New England than exists in Europe. 



On account of the enormous numbers in which both gipsy and 

 brown-tail moths existed in Massachusetts, it was considered that 

 the simplest way to secure the true European parasites was to 

 collect caterpillars and chrysalids wherever they could be found 

 in Europe, box them, and ship them directly to Boston ; this always 

 with the certainty that a certain percentage, high or low, would 

 contain living parasites which would probably issue in the adult 

 condition on the journey or after arrival in America, in which event 

 they could be cared for, reared until sufficiently multiplied, and then 

 liberated. 



A temporary laboratory for the receipt and care of specimens 

 was immediately established by Mr. Kirkland at Maiden, Mass., 

 and a careful search was begun for a suitable location for a perma- 

 nent laboratory for the care of parasites. It was considered desirable 

 that this laboratory should be placed in a region in which both the 

 gipsy moth and the brown-tail moth occurred in abundance, so 

 that there might be plenty of material for food for the parasites 

 at all times; and it was also considered of importance that a con- 

 siderable area of land should be secured which could be controlled 

 for outdoor experiments. Mr. Kirkland finally found a small farm 

 with buildings in North Saugus, the location easily accessible by 

 electric cars and sufficiently isolated. (See PI. II, fig. 1.) The 

 house was large enough to give ample room for laboratory use, 

 and at the same time furnished dwelling rooms for the state official 

 in charge. In the immediate vicinity there was a chain of large 

 woodland colonies of the gipsy moth and numerous orchards infested 

 by the brown-tail moth, as well as a large area of scrub-oak land 

 where the brown-tail moth occurred very abundantly. A portion 

 of the building occupied as a laboratory was fitted up by the State 

 with shelves, tables, rearing cages, and all necessary apparatus 

 and supplies, and the State employed Mr. F. H. Mosher, with Mr. 

 E. A. Back and Mr. O. L. Clark as assistants, to help care for the 

 parasites. 



While, as just stated and for the reasons given, the main effort 

 was made with Europe, correspondence was begun with the Imperial 

 Agricultural Experiment Station at Nishigahara, Tokyo, Japan, 

 and the Imperial Agricultural College at Sapporo, in order to secure, 

 if possible, the services of expert Japanese entomologists in sending 



