THE ORIENTAL MOTH AND ITS CONTROL 



sitic insect. Numerous broken cocoons have sometimes been noted, 

 but the larvae or pupae within them had apparently been destroyed 

 by some predator, 

 perhaps by birds or 

 squirrels. Certain 

 parasitic insects are 

 known to attack the 

 pest in the Orient, 

 and in 1917 and 1918 

 H. T. Fernalcl, then 

 professor of entomol- 

 ogy at Massachusetts 

 Agricultural College, 

 obtained shipments 

 of one of these, 

 Ghrysis shanghaien- 

 sis Walk., from 

 China. Adults of 

 this beneficial wasp 

 were liberated in Bos- 

 ton but the attempt 

 to establish it was 

 unsuccessful. 



During 1929 and 

 1930 the Bureau of 

 Entomology liber- 

 ated, at 16 points in 

 Boston and vicinity, 

 approximately 85,000 

 adults of a parasite 

 imported from Ja- 

 pan. This parasitic 

 fly, C haetexovista ja- 

 vana B.B. (fig. 7), 

 lays its egg on the 

 larva of the oriental 

 moth. The maggot 

 that issues from the 

 egg bores into the 

 body of the larva, 

 where it feeds and 

 forms its pupal case 

 (fig. 8, B). The host 

 is killed after making 

 its cocoon (fig. 8, A). 



The results obtained from liberating this fly have been very en- 

 couraging. Examinations of cocoons collected in the field in the 

 years since the first flies of Chaetexorista javana were put out have 

 shown that the parasite has not only established itself and spread 

 to a distance of at least 6 miles from the nearest liberation point 

 but has become an important factor in reducing the population of 

 the oriental moth. The extent to which C. jcwatia has multiplied 

 and increased in effectiveness is shown by the fact that only 0.78 



Figure 4- 

 of their 



The oriental moth : a, Large larvae and results 

 feeding ; b, cocoons on twig. Natural size. 



