224 
Indiana University Studies 
the galls of the two are different enough, heldae appears to 
represent the multipunctata stock on Q. lobata in the Lake 
County area. The galls of both occur on the petioles and 
young twigs as well as on the leaves of the oaks; all of the 
other known Cynips galls are confined to the leaf veins of their 
hosts. The insects of maculosa and mirabilis are similarly 
close, while the galls differ considerably. It must be con- 
cluded that distinct lines of origin and evolution are repre- 
sented by these two groups. The species furnish striking 
instances of the importance of physiologic characters in tax- 
onomy. 
The galls of Besbicus are rather more diverse than is the 
rule in cynipid genera and subgenera. In form the four 
species bear little resemblance; in internal structure they 
agree in having all five of the fundamental gall layers ; 
nutritive, protective, parenchyma, collenchyma, and epi- 
dermal; but mirabilis differs from the others in having the 
parenchyma remarkably developed into a fibrous mass which 
holds the larval cell centrally in the gall. 
The galls of the agamic forms begin development in mid- 
summer. The agamic adults emerge from November to 
February, earlier furthest north. No bisexual form of the 
present subgenus has as yet been recognized. 
Cynips (Besbicus) multipunctata (Beutenmiiller) 
agamic forms 
FEMALE. — Head no narrower than the thorax, dark rufous, black 
over a large part of the face medianly and about the mouth; the fourth 
antennal segment of only moderate length ; thorax large but not as heavy 
as in mirabilis , hardly as high as long, dark rufous with considerable 
black over the mesonotum including the scutellum; anterior parallel 
lines barely indicated; scutellum of moderate width, largely smooth, 
sparsely punctate, anteriorly depressed, the foveal depression broad, 
moderately deep, and with or without an indistinct division into foveae; 
abdomen dark rufous to blackish, generally darker dorsally; dorsal pro- 
jections of the hypopygial spine well developed but not as long as in 
mirabilis and maculosa; the cubital cell with 15 to 20 spots, the dis- 
coidal with 2 to 16 spots; length 2.5 to 4.0 mm., averaging nearer 2.5 
mm. 
GALL. — Spherical, the surface much distorted in variety heldae; 
more or less solid, largely naked, attached to the leaves or stems. Up 
to 10. mm. in diameter, averaging nearer 7.0 mm., the sphere more or 
