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Indiana University Studies 
together; without a distinct larval cell; the gall more or less hidden in 
an otherwise more or less unmodified bud ; on the species of oak on which 
the corresponding agamic form occurs. 
RANGE. — Probably wherever white oaks occur from the north- 
eastern United States, southern Canada, and the more northern Rocky 
Mountains to Florida, Texas, and Arizona, southward into Mexico. Known 
from five species which extend east of the Mississippi Valley and (four 
species) to the Atlantic Coast, and from three species confined to the 
Southwest and Mexico. The present center of distribution nevertheless 
in the Southwest. Figure 49. 
SUBGENOTYPE. — Of Acraspis: Cynips pezomachoides Osten 
Sacken = Cynips (Acraspis) pezomachoides pezomachoides. One of the 
two species originally included in Mayr’s description of Acraspis. 
Designated by Rohwer and Fagan, 1917, Proc. U.S. Nat. Mus. 53: 359. 
Of Sphaeroteras : Biorhiza mellea Ashmead = Cynips (Acraspis) 
mellea mellea. Ashmead’s genus Sphaeroteras was monobasic and estab- 
lished for mellea. 
As here interpreted, this is a southwestern and more eastern 
American subgenus, and the best known of the American 
groups of Cynips. Of the seven species of the whole genus 
Cynips represented east of the Mississippi River, five (pezo- 
machoides, hirta, gemmula, villosa, and mellea) belong to the 
present subgenus. All of these five are, however, to be ex- 
pected in the southern Rocky Mountains, and one of these 
(villosa) is known from New Mexico and Arizona. The other 
three species of the subgenus (conica, arida, and nubila) are 
not known outside of our Southwest and Mexico. We may 
expect undescribed varieties of Acr*aspis to repay some future 
explorer in the mountain regions of Mexico. 
Acraspis is known from 8 species representing a total 
of 42 varieties, for 2 of which both the agamic and bisexual 
forms are described. The typical varieties of the five more 
eastern species were all described before 1888. It is doubtful 
if additional species of Acraspis remain to be discovered in 
this part of the country, altho it is certain that numerous 
varieties of these species are not yet described. One of the 
southwestern species was described in 1881, and two are 
added in the present paper. The range of one of the more 
eastern species (villosa) was extended into the Southwest only 
last year. Thus there is no indication of the exhaustion of 
either the new varieties or species of Acraspis in that part of 
the country. 
