24 BULLETIiS^ 1028, U. S. DEPARTMENT OF AGRICULTURE. 



generation of the parasite. The records of parasitism secured from 

 fourth-stage caterpillars which represent the second or summer gen- 

 eration of A. melaiioscelibs were about the same. 



The second and fourth stages of the gipsy-moth larvae usually 

 showed the highest percentage of parasitism, but a considerable num- 

 ber of the individuals of the other stages were killed by the parasite. 

 Occasional!}^ collections were made which gave as high as 15 per cent 

 parasitism, for each of the other larval stages. In large collections 

 of larvse where all the caterpillars in sight were collected, the parasit- 

 ism obtained averaged around 10 per cent for each generation. The 

 collections from which these figures were secured contained from 

 5,000 to 20,000 larvse. 



The figures obtained from the foregoing collections should not be 

 taken as rei)resenting the value of the parasite. 



There are a great many parasitized gipsy-moth larvse which die 

 in the field before the parasite maggot has had time to develop. The 

 parasitized larvse do not eat so much as nonparasitized larvse and are 

 inclined to crawl to out-of-the-way places and often are not seen 

 by the collector. On the other hand, if one should search for the 

 hidden larvae the collection would not be representative of conditions 

 as they truly exist. 



There is each year a high j^ercentage of mortality of the gipsj^ 

 moth, which occurs whether insect parasites are present or not. This 

 mortality varies from year to year depending upon the conditions 

 which influence the contributing factors, but the average percentage 

 of mortality (barring insect parasites) for any period of years is the 

 same as for any other similar period of years, if the periods include 

 a sufficient number of j^ears to make the average a fair one. This 

 average mortality is not sufficient to prevent the increase of the 

 gipsy moth, nor is the parasitism by A. nvelanosceT/ubs great enough 

 to prevent the increase of this pest. Although the exact percentage 

 of parasitism of the gipsy moth by this parasite can not be stated, it 

 is evident that it has a very important place as a part of the sequence 

 of parasites which in conjunction with the other natural agencies 

 retards the increase of this injurious insect. 



ABUNDANCE OF A. MELANOSCELUS IN NEW ENGLAND. 



Afanteles melanoscelus^ like some of the other introduced parasites 

 of the gipsy moth, is found abundantly in rather small areas. Each 

 year since the parasite has been established these areas of abundance 

 have been found more often and over considerably more territory. 

 Until the summer of 1916 the parasite was not found in any appre- 

 ciable numbers excepting at local points in and around Melrose High- 

 lands. During the summer of that year a location at Beverly, Mass., 

 was found where A. melanoscelus was very common. During the 



