THE CHALCIDOID GENUS PEEILAMPUS, 



67 



doptera, Coleoptera, and Neuroptera, in Europe, Japan, and America. 

 Table III shows the number of each group from which Perilampus 

 has been reared in those regions where the gipsy moth is found : 



Table III. — Classification and distribution of the Icnovm hosts of the genus Perilampus. 



America. 



Europe. 



Japan. 



Hymenoptera parasitica 



Hymenoptera phj'tophaga. 



Hymenoptera aculeata 



Dlptera (Tachinidn?) 



Lepidoptera 



Coleoptera 



Neuroptera 



1 (?) 

 1 



Total. 



THE ECONOMIC ASPECTS. 



In 1906 Mr. E. S. G. Titus, at that time in charge of the Gipsy 

 Moth Parasite Laboratory, reared a few cocoons of Apanteles vime- 

 neforum Wesmael ^ from caterpillars of the brown-tail moth which 

 had been imported in the hibernating nests. From them there 

 emerged a very few specimens of a species of Mesochorus, different 

 from any known American secondary upon Apanteles and apparently 

 but not certainly European. The circumstances under which the 

 Apanteles were reared were not such as absolutely to protect them 

 from the attack of the native hyperparasites, but there was good 

 reason to believe that the Mesochorus, as well as the Apanteles, had 

 attacked the very small caterpillars of the brown-tail moth in Europe 

 the fall before. This was the first instance encountered in the 

 course of the work of parasite introduction in which a secondary 

 parasite was known or suspected to attack a primary parasite before 

 the death of the primary host. 



In 1907 this record was confirmed, and it was demonstrated beyond 

 possibility of error that there were some secondary parasites which 

 had this habit. The fact was of the greatest significance, since 

 it was one of the fixed policies of the laboratory to introduce the 

 primary parasites of the gipsy and brown-tail moths and to exclude 

 the secondary. It had been supposed that this could be accom- 

 plished by importing the living caterpillars and pupae of the gipsy 

 and brown-tail moths and rearing the parasites. The fact that 

 the primaries might be attacked before the death of their host 

 altered the situation materially and made the strictest supervision 

 of imported material necessary in order to meet the ideal which had 

 been set. 



That the relative importance of h3q3erparasitism has diminished 

 rather than increased as a result of a better understanding of the 



• As determined by Schmiedeknecht. 



