170 NEW YORK STATE MUSEUM 



How., Apaiitehs hyphantriae Riley, Apanteles parorgyiae Ashm., Ptero^ 

 mains cuproidens How., Cratotechus orgyiae Fitch, Telenomus orgyiat 

 Fitch, Frontina aleiiae Riley, Exorista griseomicans V. d. W. and Vi^in- 

 themia 4-pustulata Fabr. At Washington these parasites becanie so 

 abundant that in the autumn of 1895 about 90/0 of the larvae were 

 destroyed. In addition to the above named parasites, Dr Howard records 

 that Ichjieumon subcyajieus Cres., Ichne2imo7i coei'uleiis Cres. and Allocoia 

 thyridopterigis Riley were all observed investigating recently formed 

 Notolophus cocoons and were apparently About to oviposit. The latter, 

 he states, is parasitic upon Pimpla. 



In his study of these parasites, Dr Howard found that the conditions 

 were not uniform in all parts of the city of Washington, the parasitism 

 being more general in the vicinity of the grounds of the Department of 

 agriculture, where most of the observations were made, than in other 

 portions of the city. The difference due to locality is also shown by the 

 <* parasites in the state collection reared by the late Dr Lintnerfrom this 

 species, though his study of them was by no means so extensive as that 

 at Washington. The one occurring most abundantly was Tachina mella 

 Walk. Pivipla hirticauda Prov., a species not hitherto recorded from 

 this insect, was bred in greater numbers than any other of the larger 

 hymenopterous parasites. Most of the individuals belonging to this 

 species were reared in July, but two appearing in June and a few others 

 in August. Pimpla inquisitor Say, P. co?iqiiisitor Say and P. an7iulipes 

 Brulle occurred in about equal numbers. Of the smaller primary para- 

 sites, Pteromalus ciiproideus How. and an unnamed species belonging to the 

 same genus were about equally abundant. 



Though the list of primary parasites is long and includes some very 

 important species, many of these are in turn the victims of enemies. 

 The parasites breeding in those which prey upon injurious forms must be 

 classed as enemies to man, since they protect a species indirectly by 

 destroying large numbers of its parasites. One of the most abundant of 

 the hyperparasites reared by Dr Howard at Washington was Dibrachys 

 boucheajius Ratz. (fig. 4), it being present in such force as to almost kill 

 o^ Pimpla inquisitor the latter part of 1896. This species was also reared 

 in large numbers by Dr Lintner in 1883. It is in turn, as demonstrated 

 by Dr Howard, preyed upon by Asecodes albitarsis Ashm. The follow- 

 ing is a list of the hyperparasites of Notolophus leucostigma^ as given by 

 Dr Howard: Heiniteles townsendi Ashm., Bathythrix meteori How.,, 



'^ Determined through the courtesj' of Dr L. O. Howard. 



