Kinsey: Gall Wasp Genus Cynips 
415 
groups of oaks. On the true white oaks, hirta is known from 
four varieties on Quercus macrocarpa and two on Q. Gambelii 
and its varieties (including Q. utahensis) while gall material 
of an undescribed series in our collection was found on Q. bi- 
color (in Minnesota). Hirta is represented on the chestnut 
oaks by a variety that occurs on Q. Prinus and Q. Michauxii. 
While the inclusion of both true white and chestnut oaks by 
a single species of cynipid is not usual, neither is it uncom- 
mon, the situation being peculiar in this case because the 
commonest of the white oaks, Q. alba and Q. stellata, are not 
known as hosts of this insect. 
FIG. 70. FOUR VARIETIES OF CYNIPS HIRTA 
Showing geographic isolation of related insects. 
The seven varieties of hirta are hardly distinguishable from 
insects alone. The few insect characters available are, how- 
ever, confirmed by the distinctive galls and host and geo- 
graphic distribution of each variety. Varieties scelesta , 
macrescens, obtrectans , and undulata produce conspicuously 
ellipsoid galls, scelesta on Q. macrocarpa in sub-Canadian 
areas of the northeastern United States, macrescens on Q . 
macrocarpa in the northern Middle West, obtrectans (with a 
distinctive insect) on the same host in Oklahoma and Texas, 
and undulata on Q. Gambelii in the southern Rocky Mountain 
area. Varieties hirta and opima produce spheroidal galls, the 
first species on the eastern chestnut oaks, the second on Q. 
