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Indiana University Studies 
wings much, reduced, from 0.21 to 0.35 of the body in length, with 
hardly a trace of any of the veins; length 1.5 to 3.5 mm. 
GALL. — Small, ellipsoid to spheroidal, with faceted surfaces. Always 
monothalamous, up to 6.0 mm., usually nearer 4.0 mm. in diameter; 
symmetrically ellipsoid to spheroidal; the surfaces closely set with 
broad, polyhedral bodies, giving a faceted appearance, these bodies 
sometimes set with short, conical tubercles which make the galls appear 
superficially rougher than naked galls of pezomachoides, tho they are 
never as spiny as many of the galls of pezomachoides ; light yellow and 
green to purplish pink when young, becoming straw yellow to dirty 
brown when old. Internally compact crystalline, the walls thick, flexible 
when moist, very hard when dry; the single larval cavity central, with- 
out a distinctive cell wall. Attached to the mid-veins or lateral veins, 
on either the upper or under sides of the leaves of the true white oaks, 
the chestnut oaks, and the Rocky Mountain white oaks (known from 
Quercus macro carpa, Q. bicolor, Q. Prinus, Q. Michauxii, Q. Gambelii, 
and Q. utahensis ) . 
RANGE. — Known from Massachusetts to Minnesota, Texas, and 
Utah. To be expected everywhere in the Rocky Mountain areas and 
the eastern United States and Canada, wherever white oaks occur. Fig- 
ures 70-73. 
The young galls of Cynips hirta are to be found early in 
July. The adults emerge from early in October to the middle 
of December, chiefly in the latter half of November. The 
alternate, bisexual generation is not recognized for any vari- 
ety of this species. Judging from the experimentally demon- 
strated alternation of Cynips pezomachoides and the suggested 
alternate of Cynips prinoides , the two species most closely re- 
lated to hirta, we may expect the alternate, bisexual genera- 
tion of hirta in a simple, thin-walled cell in the buds of the 
oaks that harbor the agamic generation. 
Altho not well represented in most collections, this insect 
has proved abundant in certain localities, and may be found 
more commonly upon further fieldwork. The gall is very 
similar to some of the more naked, nearly spineless galls of 
Cynips pezomachoides, but galls of four of the varieties of 
hirta are to be distinguished by their more ellipsoid form. 
The insects of hirta are readily separated from pezomachoides 
and gemmula because they have entirely hairy abdomens 
which usually are more compressed than in gemmula and not 
as greatly compressed as in pezomachoides . 
Pezomachoides is restricted to the Q. alba and gemmula to 
the Q. Prinus groups of oaks. Hirta is known from both these 
