NATURAL ENEMIES. 



377 



of these parasites, while apparently in search of pupae. 

 There is no doubt that our birds which take small insects 

 on the wing also destroy many Hymenopterous and Dipter- 

 ous parasites. 



Pimpla pedalis (Plate 53, Figs. 7, 7a) was obtained 

 from the pupae of the gypsy moth the past season, as well 

 as in previous seasons, and was also bred in great numbers 

 from the cocoons of the tent caterpillar ( Clisiocampa ameri- 

 cana) . From about two quarts of the cocoons of the latter 

 insect only twenty-five moths were obtained, the rest pro- 

 ducing parasites, most of which were Pimpla pedalis, though 

 a few specimens of Theronia melanocephala were also ob- 

 tained. Pimpla pedalis was seen ovipositing in the cocoons 

 of the tent caterpillar ; but as I have bred this parasite from 

 larvae of Tortrix fumiferana received by mail, and reared 

 under such conditions that it was impossible for parasites to 

 approach them, I am led to believe that Pimpla pedalis, as 

 well as Theronia melanocephala, oviposits not only in pupae 

 but also in caterpillars. The fact that these parasites breed 

 in the tent caterpillar and other insects, as well as in the 

 gypsy moth, is of special interest ; for the tent caterpillars 

 pupate about four weeks earlier than the gypsy moth, and the 

 parasites emerge from them just in time to attack that insect, 

 so that this succession of hosts favors the multiplication of 

 the parasites. How these parasites pass the winter I do not 

 know, but think it very probable that they hibernate as 

 imagoes. Ichneumon grandis was taken in January, 1895, 

 hibernating in the imago stage, in a stone wall at Swamp- 

 scott, along with pupa shells of the gypsy moth and cocoons 

 of Pyrrlmrctia isabella. 



The following is a list of the European Hymenopterous 

 parasites of the gypsy moth, some of which, however, are 

 known to be hyperparasites : 



Pteromalus holiday anus Rtz. 



(hyper). 



Pteromalus pini Hartig. (hyper). 

 Pteromalus boucheanus Rtz. 



(hyper). 



Eupelmus bifasciatus Giraud. 

 Eurytoma abrotani Panz. 



Microgaster calceatus Hal. 

 Microgaster (?) tenebrosus Wesm. 

 Microgaster tibialis Nees. 

 Microgaster (?) liparidis Rtz. 

 Microgaster pubescent Rtz. = calcea- 

 tus Hal. 

 Microgaster fulvipes. 



