18 bulletijs: 1028, u. s. departmejStt of agriculture. 



very dry and shriveled, and indicated that death might have been 

 due to lack of moisture within the caj^sules. 



Xo colonies were liberated in 1914, as no importations were made 

 and the parasite had not been sufficiently well established to furnish 

 colonization material. 



All Apanteles inelanoscelus liberated since 1913 have been put 

 out while in the cocoon and have been of the summer-issuing 

 generation. Most of these colonies have contained 500 cocoons. In 

 liberating a colony the cocoons are taken to the field and emptied 

 into a small cylindrical can, which is then nailed to a tree in an in- 

 conspicuous place. A cover is placed on the can to protect the 

 cocoons from rain and birds. The adults escape through three 

 ^-inch holes punched in the can near the top. The size of the can is 

 not especially important, but a convenient can used at the laboratory 

 is 3 inches in height and 2 inches in diameter. It is necessary to place 

 a band of tree-banding material entirely around the can to prevent 

 ants from destroying the colony. 



In selecting sites for colonies, woodland areas with a light to 

 medium gipsy-moth infestation are preferable. Heavily infested ter- 

 ritory which is apt to be stripped of its foliage should be avoided. 



After the colony has been liberated a roadside tree is marked in 

 white paint with an arrow pointing to the colony and the letters A. M. 

 In the woodland near the exact spot of the colony a tree is banded, 

 with white paint. These field marks are made so that the place can 

 be found later if desired. At the same time a numbered note is 

 written for the laboratory files which explains the condition at the 

 colony site and gives directions for finding the colony. 



The colonies have been placed in groups of towns, one colony in 

 each town, as shown in the accompanying map (PL IV). This 

 method of liberating colonies was used because the parasite disperses 

 rapidly and there was considerable chance that small colonies would 

 not become established if they were placed singly at widely separated 

 locations. In this way several rather large ai-eas, from which the 

 parasite can spread to the surrounding .towns, have become well 

 stocked. 



METHODS USED TO OBTAIN MATERIAL FOR COLONIZATION. 



The stor}^ of the introduction of A. melanoscelus and the colonies 

 liberated from the imported material has been recorded earlier in 

 this paper. Two methods have been used to get material for coloniza- 

 tion since the establishment of the parasite in Xew England — first, by 

 rearing the parasite from field-collected gipsj^-moth larvae, and, sec- 

 ond, by breeding the parasite at the laboratory. 



The first method consists merely of making collections of large 

 numbers of second-stage gipsj^-moth larvae from locations where the 

 parasite is present in sufficient numbers to warrant such collections. 



