narrower (more northern Europe); the mesonotum in large part or almost entirely smooth, naked, shining; the abdomen fully twice as long as high, produced dorsally but with the second segment reaching only two-thirds or less of the way to the tip of the abdomen; the tip of the second abscissa of the radius prominently bent or enlarged (Central Europe) or not at all enlarged (more northern Europe); the length 1.8 to 4.0 mm. in two varieties.
The Central European variety divisa (q.v.) is close to the other varieties of Cynips in the same region; the more northern variety atridivisa is very near C. folii atrifolii and C. longiventris forsiusi of that region.
BISEXUAL FEMALE AND MALE.—As described for the genus and subgenus (q.v.). Very similar to the bisexual forms known for other species of European Cynips; recognizable by the characters given, differing in having the mesonotum somewhat roughened especially anteriorly about the parapsidal grooves, the mesopleuron with a limited rough spot, and the tip of the second abscissa of the radius with, perhaps, a more distinct sort of triangulate enlargement.
AGAMIC GALL.—In form a more or less flattened sphere or ellipsoid, not as soft as folii; regular in shape, not distorted in drying, up to 7.0 mm. but usually under 5.0 mm. in its longest axis; entirely smooth and naked, at first bright red in color, becoming a light rosy brown or a straw brown. The outer shell thin but distinct from the spongy, not very solid layer beneath; a large part of the gall occupied with the larval cell which is central, oval, averaging 2.5 by 4.0 mm., the cell with a distinct but inseparable wall. The galls attached to the leaf veins, on the under surfaces of the leaves of Quercus pedunculata, Q. sessiliflora, and Q. pubescens. There are records for other hosts which may apply to undescribed varieties of divisa.
BISEXUAL GALL.—An irregularly cylindrical, more or less subdivided cell on the edge of a young leaf, in a bud, or on a young shoot; characterized in more detail under the descriptions of Cynips divisa divisa form verrucosa.
RANGE.—The species known thruout Europe wherever collections have been made on oaks, and from northern Africa and Asia Minor. This range probably involves several varieties, only two of which are described.
Altho the galls of divisa are so much smaller and consequently less conspicuous than those of Cynips folii, they seem to be fully as common thruout all parts of Europe in which cynipid collections have been made. Usually 10 to 15, but at times as many as 35 (acc. Connold 1908), or even 40 or more galls (acc. Schmidt 1907) may be found on a single leaf. The similar galls of Cynips agama are to be distinguished from divisa by their smaller size, thinner walls, and more ellipsoidal
