PARASITES OF GIPSY-MOTH PUP^. 251 



settle this point at all definitely. Meanwhile it does not seem to be 

 advisable to attempt the introduction of the European sarcophagids 

 until we know whether they are an aid in the control of the moth or a 

 possible hindrance to the work of the parasites. 



The special investigations which were conducted for the purpose 

 of determining the exact status of the sarcophagids in America in 

 relation to the gipsy moth were conducted by Mr. T. L. Patterson, 

 and have been made the subject of a special report. 1 



Another series of investigations, conducted by Mr. P. H. Timber- 

 lake, upon the parasites of the pine u tussock moth" in northern 

 Wisconsin, resulted in the accumulation of evidence which pointed 

 quite convincingly to the parasitic character of certain sarcophagids 

 which he encountered in abundance associated with this insect. 

 Unfortunately it is not wholly convincing. If it could be accepted 

 at its full face value it would mean that in these flies we have a group 

 of dipterous parasites wholly distinct from the tachinids, and working 

 in a wholly different manner. The tachinids are caterpillar parasites, 

 and never, so far as has been recorded, attack the caterpillar after it 

 has spun for pupation. The sarcophagids, like Pimpla, Theronia, 

 etc., are pupal parasites and will be grouped together, oid at the same 

 time apart from the hymenopterous pupal parasites, even as the 

 tachinids as a group stand beside but apart from the hymenopterous 

 parasites of the caterpillars. 



THE PREDACEOUS BEETLES. 



It is very probable that further studies into the subject of natural 

 predatory enemies of the gipsy moth will result in the addition of a 

 considerable number of names to the list of predaceous beetles which 

 attack it in one stage or another of its existence and with more or 

 less freedom. The egg masses received from abroad have very fre- 

 quently been infested with small dermestids, and in the forests in the 

 vicinity of Kief, Russia, in September, 1910, large numbers of the 

 larvae of a species not yet determined were found feeding, to all 

 appearances, upon the eggs of the moth as well as upon the covering 

 of felted hair. 



That these larvae do actually eat the eggs was demonstrated b} r Mr. 

 Burgess during his association with the moth work as conducted by 

 the State board of agriculture in 1899 and later his observations were 

 confirmed by a series of simple experiments conducted at the labora- 

 tory. 



In the spring of 1908 a large number of cocoons of the tussock moth 

 with egg masses attached was collected in East Cambridge, Mass., 

 and from them in June a number of dermestid beetles issued, deter- 



1 U. S. Department of Agriculture, Bureau of Entomology, Technical Series 19, Part III, March 22, 1911. 



