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Indiana University Studies 
width; a small, very indefinite clouding at the base of the cubitus, a 
larger, more definite patch at the base of the cubital cell, and a few, 
darker brown, very irregular, fused spots in the cubital cell; discoidal 
cell clear; length 3.0 to 4.5 mm. 
GALL. — A large, spherical, spotted or unspotted, thin-shelled leaf 
gall with rather sparse, radiating fibers. Monothalamous. Strictly 
spherical except where flattened a bit at the point of attachment; ivory 
to apricot or more pinkish in color, some galls well covered with purplish 
spots; smooth and often shining, only very microscopically roughened, 
young galls with a microscopic, stellate pubescence; up to 26.0 mm., 
averaging under 20.0 mm. in diameter. Internally hollow except for the 
thick-walled larval cell which is up to 4.0 mm. in length, for the rela- 
tively few, silky, radiating, branched fibers that hold the larval cell in 
position, and for a few shorter, incomplete, branched fibers also located 
on the inner wall and on the larval cell. Attached by a minute point 
to a vein; usually on the under surface of a leaf, on Quercus stellata. 
Figure 197. 
EANGE. — Known from New York to Florida, Missouri, and Texas; 
probably not extending much further than this. Figures 47, 48. 
This is the oldest and most commonly known American 
species of Cynips, but it is poorly represented in most collec- 
tions. None of the published data, nor most of the collections 
I have made would indicate that it is ever abundant in any 
part of its range, but 1 have on several occasions found indi- 
vidual trees bearing more than fifty galls each. These galls 
are confined to the post oak, Quercus stellata, on the leaves of 
which they are strikingly beautiful objects. There are four 
known varieties, centricola from the Coastal Plain and its 
inland extensions, clivorum from the Southern Appalachians, 
strians from the Ozark area, and Karsch’s rubrae from Texas. 
The varieties are separable on only a few insect characters, 
and on the presence or absence of spots on the galls, and altho 
typical material from the center of each range is definitely 
determinable, hybrid material from areas between two of 
these ranges is not easily analyzed. The slow evolution in 
this species is in contrast to the more rapid evolution of such 
a species as Cynips mellea in the same range. 
The presence or absence of spots on the galls of this species 
was taken by Osten Sacken, in the original description of the 
typical variety, to vary with the age of the gall. It is possible 
that the amount of weathering has something to do with this, 
but I have unspotted galls of the normally unspotted variety 
clivorum collected on various date from October 24 to Novem- 
