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Indiana University Studies 
ing 2.5 by 4.0 mm., with a distinct wall but inseparable from the 
compact filling of the gall. Attached to a leaf vein, on the undersides 
of leaves of Quercus pedunculata and Q. sessiliflora. Doubtfully identi- 
fied on Q. tumeri (Rolfe acc. Kieffer 1901). 
BISEXUAL GALL. — Apparently very similar to that of the bi- 
sexual forms of Cynips folii (q.v.). Known only for the variety longi- 
ventris form substitutes, where it is dull green in color, with a longer, 
gray pubescence, a more sharply pointed tip, and a smaller size which 
is up to 2.0 mm. in length. On the bark at the bases of older trees, 
less often on the two-year old stems; on Q . pedunculata, Q. sessiliflora, 
and Q. pubesce?is. 
RANGE. — Known thruout Europe except in the Mediterranean area. 
The two described varieties, longiventris and forsiusi, are confined to 
more central Europe and northern Europe respectively. 
The typical variety of longiventris is apparently common 
in Central Europe. The variety forsiusi is known only from 
southern Finland and Denmark. The species is strangely 
absent from the records for Mediterranean Europe. Our only 
indication of the occurrence of the insect there is Trotter and 
Cecconi’s (1904) record for Italy without more definite 
locality, and a doubtful record (acc. Tavares 1928:44) for 
Spain. There seems no available explanation to show why 
longiventris should differ from so many other species that 
have their Central European varieties matched by Mediter- 
ranean segregates. 
Cynips longiventris and Cynips folii give striking data on 
the existence of physiologic species. The galls of the two are 
never to be confused, and yet the insects, in both agamic and 
bisexual generations, are so nearly alike that the European 
authors have usually accepted them as indistinguishable. 
Mayr (1882) thought he could distinguish the agamic females 
by the proportions of the twelfth antennal segments, some 
minor points of color, and the body length. These are the 
only distinctions made in the Kieffer (1901) and Dalla Torre 
and Kieffer (1910) monographs. Examination of good series 
of both longiventris and; folii convince me that in antennal 
and color characters the insects vary more individually than 
they were supposed to differ specifically. The average length 
of longiventris is clearly under that of folii, but series again 
show many specimens of folii which are smaller than the 
larger specimens of longiventris. On the other hand, I offer 
the characters of the scutellum (see the description of the 
