30 
Indiana University Studies 
(Q. dumosa, Q. durata, etc.) and down in the valleys, on the 
Valley white oak ( Q. lobata) there are numerous long-winged 
species, echinus (fig. 163), schulthessae, etc., which everyone 
will accept as typical Cynips of the subgenus Antron. But 
galls of schulthessae (figs. 151-153) and podelloides (figs. 144- 
145) are remarkably close, with similarities in internal struc- 
tural details (figs. 192-193) which are infallible indicators of 
close relationships. The form of internal structure here in- 
volved is known nowhere else but in the subgenus Antron. 
Such gall structures, as well as the adjacent distributions of 
these species on related oaks, lead us to believe that guada- 
loupensis and schulthessae are close relatives in spite of their 
differences in wing characters. 
There are a couple of cases of gall identities so thoroly 
guaranteeing the affinities of dissimilar insects that the 
systematists have already accepted them. These galls are the 
large, spherical, thin-shelled oak apples (figs. 262-263) which 
occur on the leaves of several 1 species of white oaks in the 
Southwest. There are two stocks, Cynips dugesi and Cynips 
bella, with seven described species in the area. The galls of 
all seven are identical, prolonged studies having* failed to show 
any constant distinctions among them. One may collect galls 
from the foothills of southern Colorado or the mountains of 
northern New Mexico and Arizona or from West Texas into 
southern New Mexico and Arizona and into Central Mexico 
without finding evidence of more than one species. But upon 
breeding insects from these galls, each area is found to have 
distinct species, with fully winged insects in only a few of 
these areas. Three of the seven insects have wings which 
are from 15 to 37 per cent shorter than the normal for the 
subgenus. Weld (1926:18-19) recognized that the species 
brevipennata with shortened wings “replaced” a fully winged 
species in the more northern portion of the Southwest, but 
the contribution which these species offer to the problem of 
the origin of species needs further emphasis. 
The original concept of Acraspis was based on the well- 
known, short- winged species pezomachoides and erinacei (fig. 
3) of the eastern United States. All of the close relatives of 
pezomachoides are similarly short-winged insects in the 
agamic generation; but ever since Triggerson’s studies (1914) 
of the life history of Cynips pezomachoides erinacei we should 
