272 
Indiana University Studies 
which is the first sign of wing mutation among Cynipidae. 
1.17 may be taken as the ratio characteristic of the subgenus 
to which pallipes belongs. 
The wing-body ratio in pallipes rules the other species of 
Acraspis, namely, villosa and mellea out of consideration as 
alternates. 
Villosa is further ruled out by having Q. macroearpa as its 
only eastern American host. 
Mellea is further ruled out by its nearly simple tarsal claw. 
The claw of pallipes is toothed. Moreover, mellea varieties 
have an entirely clear cubital cell, and they rarely occur on 
Q. alba . 
The only eastern American Cynips left for consideration as 
a possible alternate of pallipes is some variety of fulvicollis. 
Fulvicollis and pezomachoides are the only Cynips common on 
Q. alba in the northeastern quarter of the United States. 
Nothing in the structure or the life history data precludes 
the consideration of pallipes as the alternate of fulvicollis 
unless it is the hypopygial spine. The spine of pallipes , while 
broader than in Acraspis or Atrusca, is more elongate ven- 
trally than in the short-winged, agamic forms of Philonix 
fulvicollis. We have, however, some experience that may clear 
up this difficulty over the spine, for the spine of the short- 
winged, agamic Acraspis is almost always blunt and even 
truncate, while the spine of the bisexual form is slender. 
Finally, the position of pallipes in Philonix is further con- 
firmed by our recognition of Cynips plumb ea ( q.v .) of the 
Southwest, as a species of Philonix. The wing-body ratio of 
plumb ea is 1.17, precisely the ratio for pallipes. The hypo- 
pygial spines of plumbea and pallipes are also subgenerically 
related. 
Cynips (Philonix) fulvicollis is an exceedingly common 
insect over a wide area of the eastern United States, and its 
bisexual forms should, at any rate, be insects as common and 
as easily secured as the pallipes material we have recovered 
during the past year. 
It remains to add that if pallipes belongs to the species 
fulvicollis, it must represent the variety fulvicollis, for the 
types of pallipes came from southern Connecticut which is 
well within the range of the agamic fulvicollis. 
