162 
ment of tlie pupa is rather narrowly truncate, Avith a small slender 
spine on each side of the truncation, and a shorter one beneath each 
of these. 
Considerable numbers of another species of parasitic larva were 
taken by Mr. Kelly at Elliott, 111., August 29 and September 20, 
1906. These were evidently white-grub parasites, as the remains of 
the grubs were still clinging to several of them. This species is still 
in the larval stage at this writing. 
Three yellow coarcate meloid larvae were also found by the same 
assistant in an infested oats field with the remnants of white-grubs 
attached to them, and another was taken in a similar condition Oc- 
tober 10. These specimens have not yet matured. 
Pyrgota iindaia Wied. — One of the most interesting parasitic 
enemies of the white-grubs is a large, rather miusual-looking fly of 
the family OrtaUdcu, noticed by Mr. J. A. West, an assistant of my 
office, as abundant among the beetles at night. Now and then May- 
beetles were seen to drop to the earth, trying to rid themselves of the 
adult flies which were clinging to their backs, each with the last 
segment of the abdomen thrust in between the wings and wing- 
covers of the beetle and firmly held in place over the middle of the 
abdomen. The flies were apparently thus thrusting their eggs into 
the backs of the beetles through the thin dorsal skin beneath the 
wing-covers. The tip of the abdomen of the female fly is admirably 
adapted to this object, being hard and subconical, and directed down- 
wards at a right angle to the axis of the body. 
The relations of these insects were experimentally determined 
by confining, June 9, 1906, adult May-beetles in a breeding-cage 
with several of the flies. These would light on the backs of the 
feeding beetles, which would at once drop to the ground with the 
flies clinging to them. Whenever a beetle spread its wings for flight 
the insect on its back inserted the tip of its abdomen between the 
May-beetle's wings, evidently depositing an tgg in its back. Beetles 
so treated lived for some days, and then began to die. On the 27th 
of June, five of the beetles were dead, and in the bodies of two of 
these, dipterous maggots were found. July 10, three of the beetles 
contained each a dipterous puparium, which remained unchanged 
until May of this year, when all produced adults of P. undata. Au- 
gust 29 and September 20, 1906, several puparia were found in the 
bodies of dead May-beetles, and these, kept in breeding-cages 
through the winter, produced adults of P. midata May 14 and 17, 
1907. Like experiments begun during the present year have pro- 
gressed similarly to the time of writing. Adult flies of this species 
