PARASITES OF GIPSY-MOTH CATERPILLARS. 199 



In some instances they appear to be identical. In others it may be 

 possible to find minor structural characters which, together with the 

 difference in their habitat, will make it worth while to designate them 

 by different names. Some very distinct species are peculiar to 

 Europe or to Japan, and remain unrepresented by any nearly resem- 

 bling them in the other country. 



In 1909, as the immediate result of colonization work carried out 

 under the happy auspices already described, it was possible to 

 collect large numbers of Apanteles fulvipes cocoons under perfectly 

 natural conditions in the open in America. This was accordingly 

 done, with the result that no less than 18 additional hyperparasites 

 were added to the list of those which attacked this host. Some of 

 these were rare, others very common in this connection. A few 

 appear to be undescribed. 



The most interesting thing about them taken as a group, is the 

 general resemblance which they bear to the similar groups of Euro- 

 pean and Japanese parasitic Hymenop- 



tera having identical habits. Appa- H^ 



rently there are about as many points aL, 



in common between the American para- PSSt - "** 



sites of Apanteles fulvipes and the Japa- - ji» fifl 



nese or the European as there are be- i|pfc ^ 



tween the European and the Japanese. Hill 1 iNfe aB^L-''** 



In the course of the work a total of jf^ r " \SH^Ik ^fek 

 5,456 cocoons of Apanteles fulvipes was ^,J\7M^m t ' '.w^aHBS 

 collected from several of the recently ^ ^/j^tKmK ' SF 



established colonies, but principally C ^^W \ & # 

 from two, representing the first among YiQ.u.-A V mteies fuivi V es: cocoons from 



those planted in 1909 and in both of which Apanteles and its secondaries 

 . . , , . , have issued, as follows: a, A panteles ful- 



which a second generation occurred. vipes; b> Hypopteromaius; c, mmiteies 



Of this total, 1,531, Or 28 per Cent, had ^ d ' Dibrachys; e, Asecodes. En- 



produced the Apanteles at the time of 



collection; 2,373, or 44 per cent, were attacked by secondaries (fig. 

 34) ; 634, or 12 per cent, were destroyed by various predatory insects, 

 ants, etc.; and 918, or 17 per cent, remained unhatched in October, 

 1909. Among the unhatched cocoons was a considerable proportion 

 which contained the hibernating larvse of Asecodes, Elasmus, and 

 Dimmockia. In more than one instance, too, hatching was prevented 

 by superparasitism, and in others death probably resulted through 

 the attack of predatory bugs. On at least one occasion Podisus sp. 

 was found with its proboscis thrust through the wall of the cocoon 

 and feeding upon the parasite larva or pupa within. 



An idea of the variety of secondary parasites reared is conveyed 

 by the tabulated list following. 



