Kinsey : Gall Wasp Genus Cynips 
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in the Museum of Comparative Zoology, the U.S. National Museum, the 
American Museum of Natural History, the Field Museum, the California 
Academy, the Illinois Laboratory of Natural History, the British and 
Vienna Museums, and Stanford University. Labelled Oakdale, Tennes- 
see; galls November 5, 1928; insects December 1, 8, 15, and 22, 1928; 
Q. alba ; Kinsey collector. 
In the southern Highlands of Central and Eastern Tennes- 
see, the Carolinas, and more northern Georgia, Cynips pezo- 
machoides is represented by a small insect which produces a 
small, nearly naked or at the most a slightly bristly gall that 
is very similar to the gall of variety pezomachoides but rec- 
ognizably distinct over this territory. One who has collected 
these small galls during the cold fall rains of the southern 
hill and mountain country cannot fail to have realized that 
they stick to the wet soil unlike the entirely smooth galls of 
pezomachoides, and yet are so much smaller than the spiny 
galls of any other variety of the species that they elude one’s 
cold finger-tips in an exasperating way. 
The insects bred from these galls are puzzlingly variable. 
Some of them approach true wheeleri of the most northern 
parts of the United States. Some of them seem good pezo- 
machoides. Most of them are everything between the two 
extremes. This extreme variation and the occurrence of both 
wheeleri and pezomachoides in the population suggests that 
this variety is of hybrid origin from the two varieties named. 
The uniform variation of this population everywhere over this 
considerable range, its rather distinctive gall, and the absence 
of any other representative of the species from most of this 
area are considerations entitling this hybrid to taxonomic 
rank, just as another hybrid, tuheeleri x derivatus, is the well- 
known variety erinacei of the more northern Middle West. 
The occurrence of variety pezomachoides or its close relative 
derivatus over so much of the South, suggests that the pezo- 
machoides heritage of advena dates from a time when pezo- 
machoides or its ancestral stock covered these southern 
highlands as well as the lowlands. The wheeleri blood in 
advena probably came in during the Pleistocene glaciation. 
Most of Central and Eastern Tennessee, excepting the Valley 
of the Tennessee River, is hill or mountain country connected 
by way of the northeastern corner of the state with the rest 
of the Appalachian system, and thru these mountains the 
northern wheeleri appears to have migrated as far south as 
