302 PARASITES OF GIPSY AND BROWN-TAIL MOTHS. 
Not very much that is definite can be said of the seasonal history 
of Pales. It undoubtedly will require another host than the cater- 
Fic. 71.—Pales pavida: Second-stage larva in situ in 
basal portion of integumental ‘‘funnel.’? Much en- 
larged. (Original.) 
pillar of the brown-tail moth in 
order that it may complete its 
seasonal cycle, but that it will 
find such a host is pretty cer- 
tain. It would rather appear, 
from what has been observed, 
that it will attempt to hibernate 
as an adult. Whether or not it 
will be able successfully to do 
this in New England remains to 
be proved. 
It has occasionally been reared 
as a parasite of the gipsy moth, 
and if successfully introduced 
into America it ought to be of 
some assistance in this role also. 
Unfortunately, as a parasite of 
the caterpillar of the brown-tail 
moth, it does not issue until 
about the time when the moth 
would have issued had the individual remained healthy. It requires 
some little time for the females to develop their eggs, and it is not 
at all likely that, like Compsilura, it will be found to pass one genera- 
tion upon the caterpillars of the 
brown-tail moth, and the next 
upon the gipsy-moth caterpil- 
lars. 
ZENILLIA LIBATRIX PANZ. 
This parasite, like Pales, de- 
posits its eggs upon foliage to 
be eaten by its host, but, unlike 
Pales, it has not been reared 
through its stages in the labo- 
ratory. Like Pales, it is south- 
ern in its distribution, and in 
relative importance they are 
about equal, judging from the 
numbers of each which have 
been reared at the laboratory. 
It was colonized in small 
Fic. 72.—Pales pavida: Integumental ‘‘funnel,’? show- 
ing orifice in skin of host caterpillar. Much enlarged. 
(Original.) 
numbers in 1906, in larger numbers in 1907, and in very small num- 
bers subsequently. The circumstances attending its colonization are 
