17 
month. There are other insects, however, in the early part of the 
season upon which the Pirnplas do oviposit; yet it is doubtful whether 
under any circumstances there are more than six or seven generations 
annually. 
As abundant and as hardy as this species seems to be, it does not 
escape the attacks of enemies of its own. A specimen of Euscliistus 
servus was observed to capture an adult female of this Pimpla when she 
was engaged in oviposition. At least two secondary parasites have 
been reared from its cocoons, viz, Dibrachys boucheanus and AUocota 
thyridopterigis, and it is altogether likely that one or more of the other 
hyperparasites mentioned will feed upon this species. It has a distinct 
friend, however, in Asecodes albitarsis, which is parasitic upon its prin- 
cipal enemy, the Dibrachys. Details concerning the three species will 
be given later. 
The completeness of the destruction of the Pimpla by the Dibrachys 
and by other causes during the latter part of 1896 was surprising. 
About one cocoon in forty contained living Pimpla larva 1 . As illustrat- 
ing a common condition of affairs in December, the result of a careful 
examination of a bunch of thirteen cocoons of Pimpla found within a 
single cocoon of Orgyia collected December 14 is here given : 
Cocoon No. 1 contained dry fragments of the Pimpla larva, four full-grown larva', 
of Dibrachys boucheanus, three larva? just transforming (having already voided the 
meconium) and one pupa of the same. 
Cocoon No. 2 contained a dried-up larva of the Pimpla and its meconial grains. 
Cocoon No. 3 contained the rotten body of a Pimpla larva. 
Cocoon No. 4 had a small hole in its side and shriveled and mutilated remains of 
Pimpla larva, the meconium grains and pupal exuvia of a number of specimens of 
the Dibrachys. 
Cocoon No. 5 contained shriveled larval skin of Pimpla and white meconial grains. 
Cocoon No. 6 contained rotten body of Pimpla larva. 
Cocoon No. 7 had a small hole and contained one pupa skin of Dibrachys, one sound 
pupa of same, five masses of Dibrachys meconial grains, a fragment of skin of a 
Pimpla larva, and two larva* of a dipterous insect, probably the little scavenger fly, 
Gaurax anchora. 
Cocoon No. 8 contained a developed but contracted and somewhat mutilated male 
of the Pimpla, and seven larva? and four pupa? of the Dibrachys. 
Cocoon No. 9 was very thin and not completed; contained shriveled body of a 
Pimpla larva which had died before finishing its cocoon. 
Cocoon No. 10 contained a bit of Pimpla skin and fragments of an unknown pupa, 
the adult of which had issued through a hole in the Pimpla cocoon. 
Cocoon No. 11, same contents as No. 10. 
Cocoon No. 12 contained four larva? and two pupa? of the Dibrachys and a strip of 
Pimpla skin. 
Cocoon No. 13 contained a shriveled and mutilated male pupa of the Pimpla and 
six larva? and one pupa of the Dibrachys. 
Very many more Pimpla cocoons were opened at this time, but the 
above is typical of nearly all and includes all of the characteristics 
except that at rare intervals a hibernating and healthy Pimpla larva 
would be found, or rather a cocoon mass all containing healthy larva3, 
for, in general, the conditions were about the same in each mass. 
11859— No. 5 2 
