58 
Indiana University Studies 
sett’s type material was obtained by cutting mature adults 
from galls and by capturing them as they were flying about 
the oak trees to oviposit. The galls of this agamic form 
are found on the leaves in late summer, but do not mature 
until very late in the fall as the leaves are falling. Most of 
the galls have by then become detached from the leaves, and 
are soon lost on the ground. By sifting the soil, sand, and 
leaf-mold, Bassett succeeded in the spring in obtaining galls 
which contained living wasps. The growth of the insect is 
probably very dependent upon moisture and temperature con- 
ditions of the sort found on the ground thruout the winter 
months, and the minute galls, with their thin walls, dry out 
very soon after collecting, explaining the difficulties in breed- 
ing the insect. Bassett found insects of this species in numbers 
over an oak, on a warm spring day, ovipositing in the buds 
of the tree. He further states that ‘Tn the latter part of May 
and the beginning of June the young galls were nearly full 
grown and as abundant as ever before.” This last must apply 
to a spring generation, for the galls of the agamic form are 
not mature until September or later ; and inasmuch as Bassett 
failed to differentiate the spring galls it would appear they 
are similar to the agamic galls, similarly placed on the leaf. 
The insect of the spring form may be agamic (as with the 
closely related saltatorius) , or bisexual as with other species 
of Diplobius, and it will be interesting to determine this 
deflnitely. These data have been published for twenty-three 
years, but have apparently been overlooked as a record of 
heterogeny. 
The type variety is on Quercus hicolor, and the records 
for other hosts will prove to represent distinct varieties. 
The type locality is in Connecticut. The Ontario, Illinois, 
Mississippi, and Texas records will undoubtedly represent as 
many distinct varieties. The oaks, Q. hicolor, Q. macrocarpa, 
and Q. stellata, belong to a single group, but Q. Michauxii 
belongs to the group of chestnut oaks. If the last record 
proves correct, the insect would appear to occur on species 
of both white and chestnut oaks over all of the eastern half 
of the United States, with a possibility of upward of 80 
varieties. Mr. Frank A. Leach has collected a very similar 
but slightly different gall on Q. lohata and Q. Douglasii from 
localities in central California; it is possible these will prove 
