170 



PARASITES OF GIPSY AND BROWN-TAIL MOTHS. 



As soon as females of Anastatus were secured, some of these eggs 

 were removed from storage and found to be dead, with the contents 

 partially decomposed. Nevertheless an attempt was made to use 

 them, and the parasites were given their choice between them and 

 others which contained embryonic caterpillars. 



A few days after their emergence the females began to betray an 

 interest in both sorts of eggs, and were several times observed in the 

 act of oviposition or attempted oviposition. Apparently this was 

 successfully accomplished, but without further results, for no second 

 generation resulted. The experiment served one purpose, however, 

 in indicating beyond reasonable doubt that the insect actually was a 

 parasite upon the eggs of the gipsy moth, and not upon any etrance 

 form of insect life accidentally included. 1 



W 



Fig. 12. — Anastatus bifasciatus: Adult female. Greatly enlarged. (From Howard.) 



The exposure of the imported eggs to warmth for the purpose of 

 hastening the emergence of any parasites which they chanced to con- 



1 How great is the likelihood of error when parasites are reared from unbroken egg masses has several 

 times been demonstrated in the course of the investigations and rearing work at the laboratory. Upon 

 several occasions small Lepidoptera have been reared from egg masses, and more than once their para- 

 sitized pupse have been found. Eggs of other species of insects, and occasionally parasitized scale insects, 

 have also been found attached to bits of bark to which egg masses were attached. Very frequently cocoons 

 of Apanteles fulvipes are found, wholly or partially covered by the egg mass, and from them several species 

 of hibernating secondaries have been reared. There is a record of a minute eulophid, allied to Entedon, 

 having issued from a small lot of eggs which had been separated from nearly every trace of foreign matter. 

 It was thought then and is still believed that these came from the eggs themselves, and that they were 

 actually parasitic upon either Anastatus or Schedius, but when the material from which they issued was 

 examined two or three cocoons of Apanteles fulvipes were found mingled with it, and what might otherwise 

 have been a clear record was spoiled. 



There is in Japan alimacodid moth— Parasa sinica Moore (hilarula Staud.), as determined by Dr. H. G. 

 Dyar— which appears habitually to seek out the gipsy-moth egg masses as a site for pupation. The larva 

 buries itself in the mass before spinning its cocoon, and from outward appearances its presence is hardly 

 noticeable. More than 2.5 of these moths have been reared under these circumstances from imported egg 

 masses, or their cocoons have been found and destroyed. 



