S6 



of them. Prol)aI)ly such work is being carried on at the present 

 time on by far the largest scale in connection with Gipsy Aloth 

 and Brown-tail Moth control work in \ew England. .As is well 

 known, the Gipsy Moth has been established nearly half a cen- 

 tury in New iuigland, starting from a suburb of JJoston and 

 spreading out in all directions, until it is now present in the east- 

 ern half of Massachusetts, the northeast corner of Rhode Island, 

 a large portion of southeastern New Hampshire, the southwest- 

 ern corner of Maine, and a few scattered places in central Massa- 

 chusetts and in Connecticut. The caterpillars defoliate most 

 kinds of forest, shade and orchard trees and shrubs, and have 

 threatened the destruction of all such in that region. The Brown- 

 tail Moth, another European pest, occupies the same region, and 

 has a somewhat wider range of distribution. The two together 

 form a very serious menace in that region, and to the whole of 

 the country as well, for they are continually spreading in spite 

 of strenuous efforts to keep them in check. 



Six years ago, work was begun on the introduction of the 

 European parasites of these pests. Investigation has shown that 

 they have numerous parasites in their native habitat, and that 

 they are usually kept under control by them. Hence, their intro- 

 duction to America was started and was already being done on an 

 extensive scale in 1906. Hundreds of boxes of parasite material 

 have been imported each year since then, mostly from (iermany, 

 France and Austria, also a considerable from Japan. This ma- 

 terial consisted of egg-masses, larvae, and pupae of the Gipsy 

 Moth ; and winter webs, larvae, and pupae of the Urown-tail 

 Moth. The handling of such a large quantity of material re- 

 quired a large number of cages, and insectaries, as well as an 

 appropriately ccjuipped laboratory. This was established in 1907, 

 at Melrose Highlands, Mass., a suburb north of lioston. 



From all this material, large numbers of parasites bred out, 

 consisting of (|uite a number of species, and attempts were made 

 to establish them in favorable localities. Some have succeeded 

 well, others fairly, and some have ])robably failed, though how 

 many will not be known for a certainty till later on. The latest 

 rei)ort on the work gives an indication of what can be expected, 

 and it looks very enccniraging for some of them. 



When stuclied in their native countries, these moths were 

 found to have parasites attacking them in all the }ounger stages; 

 one or more attacking the eggs ; many species attacking cater- 

 pillars ; and several attacking the jiupae of their hosts. Many 

 of these have been reared at the laboratory; some of them for 

 a mimber of generations, as well as breeding tlu-m out ot' im- 

 l)orted material. 



( )f the egg-])arasites of the Gijjsy Moth, one lioni japan 

 (Sclicdius), was reared through ten generations in one vtar in 

 the laboratory, and several hundred thousand liberated ; but ap- 

 l)arently it failed to l)ecr)me establisiied, or at any rate, not so 

 well as it was at first expected that it would. It bred during the 



