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does sometimes normally infest and attack insects exposed above 
ground by their habits, burying them as a matter of instinct after 
it has placed its egg. Tiphia has not, in fact, been studied as an in- 
dependent species, but all the data concerning its habits and life 
history have been gathered in the course of studies of the white- 
grubs. 
The tgg of Tiphia remains firmly glued to the back of the chosen 
grub, and hatches in seven to ten days. The young larva breaks its 
way out from the egg at one end, and, although it begins at once to 
feed, it does not at first free itself from the shell, but as it grows 
this finally splits and breaks away. When it first emerges the larva 
measures slightly more than a millimeter in length. From our scanty 
data it appears that it takes about two weeks to get its full growth, 
and that it doubles its size in the last two days of its larval life, dur- 
ing which it is engaged in devouring the body of its host. Previous 
to this time it has been adherent to the skin of the grub whose fluids 
it has lived upon. When full grown it is from two thirds to four 
fifths of an inch in length. 
The cocoons are cylindrical ovate, from 17 22 mm. long, clay- 
colored at first, and wood-brown or cinnamon-brown when older. 
From our observations thus far made it appears that the larva 
hibernates within the cocoon, not pupating until the following 
spring. The adult emerges from a little one side of the larger end, 
in which it leaves a ragged and irregular opening. In several cases 
the abundance of these conspicuous brown cocoons in the earth was 
such as to indicate an enormous destruction of white-grubs, and 
there is no doubt that this parasite is an important agent in checking 
destructive uprisings of these insects. 
That this wasp, parasitic on white-grubs, is itself parasitized, is 
shown by the results of observations made on Tiphia cocoons col- 
lected April 27, 1906, and kept in breeding-cages during the sum- 
mer. From these emerged, July 7, 16, and 31, adult bee-flies {Bom- 
byliidcc) of the species Bxoprosopa fascipcnnis, each freeing itself 
from the Tiphia cocoon by cutting out a circular piece at the larger 
end. The eggs from which these flies resulted were probably laid 
on the Tiphia grub in 1905, before the cocoon was spun. 
Miscellaneous Insect Enemies. 
MacroplitJialina disjnncta. — This little tachinid fly was men- 
tioned in my Seventh Report as bred repeatedly from dead white- 
grubs, but I was nevertheless uncertain that it was a parasite. Lately 
its parasitic nature has been proven by repeatedly breeding it from 
