194 



PARASITES OF GIPSY AND BROWN-TAIL MOTHS. 



gipsy moth is proved to be identical with that which goes under the 

 same name and attacks one or another of such a variety of hosts, no 

 expense ought to be spared in attempting its introduction; always 

 provided, of course, that the attempts already made prove not to be 

 successful. 



The story of these attempts, as told in the popular bulletin by the 

 junior author, issued from the Massachusetts State forester's office 

 in the spring of 1910, may well be quoted here, since there is little 

 to be added to it. 



Although this was almost the first parasite of the gipsy moth which attracted any 

 attention in Massachusetts, and the first which it was attempted to import after the 



beginning of active work, it was one of the last to 

 be liberated under satisfactory conditions, and 

 its establishment in America is not yet certain. 

 Extraordinary methods were necessaiy to bring 

 it to America living and healthy, and it was not 

 until Prof. Trevor Kincaid, who was selected by 

 Dr. Howard as the best available man, for the 

 purpose, visited Japan and personally superin- 

 tended the collection and shipment of the co- 

 coons, that success was achieved. The story of 

 Prof. Kincaid's experiences and of the difficulties 

 which he met and overcame is interesting. He 

 was accorded great and material assistance by 

 the Japanese entomologists, and the work inaugu- 

 rated by him in 1908 was continued with even 

 greater success in 1909. 



The adult parasite [fig. 31] deposits a number 

 of eggs beneath the skin of the active caterpillars, 

 and any stage, from the first to and possibly in- 

 cluding the last, may be attacked. The larvae, 

 hatching from the eggs, become full grown in 

 from two to three weeks, and then work their 

 way out through the skin of the still living cat- 

 erpillar [fig. 32], within the body of which they 

 fed. Each spins for itself immediately afterward, 

 for its better protection during its later stagee, 

 a small white cocoon. The number of parasites nourigjied by a single host varies in 

 accordance with its size. There may be as few as 2 or 3 in very small caterpillars, 

 or 100 or more in those which are nearly full grown. 



The unfortunate victim Of attack does not, as a rule, die immediately after the 

 emergence of the parasite larvae and the spinning of their cocoons, but it never volun- 

 tarily moves from the spot. Its appearance, both before and after death, surrounded 

 by and seeming to brood over the cocoons, is peculiar and characteristic, and once 

 seen can never be mistaken [fig. 33]. 



There is ample opportunity for two generations of the parasite annually upon the 

 caterpillars of one generation of the gipsy moth. This is the rule in the countries to 

 which it is native, and is to be expected in America. 



The parasite was described from Europe more than seventy-five years ago, and has 

 been known to be a parasite of the gipsy moth for a long time. Later it was described 

 under a different name from Japan, and the Japanese parasite was for a time consid- 



Fig. 32.— Apanteles fulvipes: Larvae eav 

 ing gipsy-moth caterpillar. Enlarged 

 (Original.) 



