28 
Indiana University Studies 
had shown that gall structures are significant measures of an 
inherited physiologic capacity of these insects. Again, the 
gall of teres occurs on the leaves of a mountain form of the 
Oregon white oak (Q. garryana semota) in the southern 
Sierras adjacent to the Central Valley of California (fig. 28), 
and all of our experience with the distribution of species had 
lent support to a corollary of the so-called Jordan’s Law, to 
the effect that the most closely related species occur in adja- 
cent areas. But teres (fig. 162) was a flea-like insect with 
short wings not a quarter of the length of those of clavuloides, 
and it had been placed in a genus which contained none but 
short- winged species. Only the hypopygial spines of the two 
insects were similar (figs. 188, 190), but we had found that 
these spines are of great phylogenetic significance; and con- 
sidering the spines, the galls, and the distribution data, the 
conclusion seemed inevitable that clavuloides and teres were 
close relatives. 
As we have extended our study to other Cynips, we have 
repeatedly disclosed similar relationships between many other 
short-winged and long^winged species, until we are forced to 
believe that the genus includes 42 subapterous forms which 
have originated more or less directly from long-winged stocks 
within the genus. Our bases for the recognition of these 
affinities are: 
1. Close identity of galls, as already explained; 
2. Occurrence in adjacent ranges, as follows from Jordan’s Law 
and from our other cynipid data; 
3. Close taxonomic affinities between hosts of the insects; 
4. Possession of similar hypopygial spines, tarsal claws, and an- 
tennal counts, altho we shall show in a later paragraph that dissimilar 
spines are not evidence of lack of relationships; and 
5. Utilization of the bisexual form (where known) as more primi- 
tive than the agamic form in these insects (Kinsey 1920:369). 
A few typical instances will illustrate our use of these bases. 
Turn first to the case of the long-winged Cynips acraspiformis, 
which Weld (1926) recognized as a good species of our pres- 
ent genus, altho he was puzzled to observe that it had a gall 
(fig. 304) similar to that of a short-winged Acraspis! The 
map (fig. 59) shows the range of this species. From its dis- 
tribution and near identity in all structural characters, the 
closest relative of the long-winged acraspiformis is certainly 
the long-winged expositor (fig. 340) of eastern New Mexico 
