35 
course of the Orgyia observations, and all practically between April 16 
and May 18, 1896, in the jars containing cocoons of the tussock moth 
collected in March and early April. Of the eight specimens, four were 
males and four females. The probabilities are this species overwinters 
within the cocoon of its 
host. What its true host e 
may be we can only sur- 
mise. Itis probably one of 
the Hemitelines parasitic 
upon Pimpla inquisitor. \ 
Dibrachys boucheanus 
(Ratzeburg). 
This widespread and 
very abundant hyperpara- 
site is common in Europe, 
and was frequently reared 
by Ratzeburg, Brischke, 
and later observers, from different hosts. Ratzeburg, in the first volume 
of his Ichneumonen der Frostinsecten, pages 196-197, states that he 
reared a number of specimens as secondary parasites in the year 1842, at 
the close of the feeding period of Liparis dispar (the gypsy moth). He 
took many Microgaster cocoons in July of that year from the larvie of 
the gypsy moth found dead upon the trees.. Hardly half of the Micro- 
Fa. 17.—Habrocytus thyridopterigis—enlarged (original). 
IGu1se— Dibrachys boucheanus: a, larva; b, pupa; c, adult female—greatly enlarged; d, head of larva; 
e, antenna of adult—still more enlarged (original). 
gasters issued from these cocoons, the remainder giving forth this 
hyperparasite, which issued from needle-like holes in the cocoons, the 
true makers of the cocoons issuing from holes made by cutting off cir- 
cular caps. He found that in some cases the larvie of the Microgasters 
were wholly eaten out by the parasite and prevented from pupating. 
In other cases the larve retained sufficient strength and substance to 
