344 
Indiana University Studies 
National Museum has material bred March 30 (in 1916). 
From the galls I collected early in January (1920) few of the 
adults had yet emerged, but after the middle of the month few 
adults were left in the galls. 
If there are differences between the insects of russa and 
variety nubila, the individual variation is great enough to 
obscure the varietal distinctions. The galls of the two insects 
are also very similar, having the same form and structure but 
differing markedly in the coloring of the hair-like, spiny coat- 
ings. All of the galls from north of Tucson are rich russet 
in color, representing variety russa; the galls from south of 
Tucson are of a fine, wine-purple color, representing variety 
nubila. I am establishing russa on the color of the gall and 
the distinctive geographic range. A geographic segregation 
that proves at all constant should be recognized, and it seems 
warranted to provide a name for data which may be considered 
a unit in its biologic significance. 
There are numerous other instances in this genus of prac- 
tical identities of the insects bred from distinct galls. Cynips 
echinus echinus and Cynips echinus douglasii; Cynips echinus 
schulthessae and C. echinus vicina; Cynips mirabilis and C. 
maculosa; Cynips multipunctata and C. heldae, are pairs of 
nearly or closely identical insects inhabiting distinct types of 
galls. If the color of a nubila gall is controlled by the insect, 
as most galls would justify us in believing, then constantly 
distinct colors may be considered expressions of the inherited 
make-up of the cynipids. It may be suggested, of course, 
that russa galls are faded specimens of nubila, but nubila 
fades purplish white instead of russet. There have been avail- 
able for my examination many galls of both varieties collected 
at various dates between November and the middle of Feb- 
ruary, and none of them gives any evidence that the color 
will change from purple to russet with age or advancement 
of the season. That the hosts are not responsible for the 
color difference is evidenced by the occurrence of both varie- 
ties on both Q. arizonica and Q. oblongifolia. Weld also re- 
cords galls on Q. reticulata (= Q. diversicolor Trelease) in 
the Santa Catalina Mountains. I covered considerable terri- 
tory in the Santa Catalina Mountains, finding the russet gall 
common there, and I cannot believe that I overlooked the wine- 
purple galls of nubila which were, on the other hand, common 
in the Santa Rita Mountains. Two of the 40 clusters of galls 
