Callirhytis lanata (agamic)

Zopheroteras compressum (agamic)

Antistrophus silphii

Antistrophus laciniatus

Antistrophus rufus

Antistrophus minor

Diastrophus potentillae

Antistrophus bicolor

Aulacidea harringtoni

Dryophanta lanata, n. sp.

Galls. During late summer and autumn the galls of this species are found on the under side of leaves of Quercus rubra and Q coccinea, appearing externally as little bunches of compact brown wool and hardly distinguishable in outward appearance from the galls of Andricus flocci Walsh. The galls seldom occur singly, but usually in clusters of from four to eight. A cluster of eight galls when fully grown will measure about 3/8 of an inch in width by 5/8 of an inch in length. An individual gall when denuded of its covering is in the form of an irregularly shaped cone with a bulging base, the diameter of the base being three or four sixteenths of an inch, which is nearly twice the height. 

The galls fall to the ground in the autumn in advance of the leaves, and the flies emerge the following summer. The galls are abundant at Ames, Iowa and I have taken a number in the vicinity of Champaign, IL. 

Described from two bred females from galls taken at Ames, Iowa. Male unknown.

Acraspis compressus n. sp.

Gall.--Small sub-globular bodies from 2 to 3 mm in diameter attached to the under side of the leaves of the red oak, Quercus rubra, in the fall, about the time the leaves are beginning to turn brown. The galls appear like wax, and are either pure white or tinged with red while on the leaves, and when cut into are fleshy and juicy like a potato. The galls fall to the ground with or a little before the leaves, and each develops a single larva which gets its growth in the fall but does not emerge until the following summer. Only a very thin shell of the gall is left after the fly emerges. 

Antistrophus silphii 

Galls. — Abrupt sub-globular swellings from 1 to If inches in diameter at the tips of the stems of Silphium integrifolium and perfoliatum (Plate IX., Fig. 1). The inner portion of the gall is made up almost entirely of a rather dense pithy material that cuts with some difficulty. Interspersed through the gall are numerous oval larval cells, and also open spaces or cavities that do not contain insects. (Plate IX.,Fig. 2.) The larval cells are not woody, as is usually the case in cynipidous galls, but their walls are of pith like the sur-rounding gall substance.

These galls are very common in the vicinity of Champaign, on stems of Silphiiim integrifolium, and Mr. Hart had collected similar galls at Normal, III, from S. perfoliatum, from which flies were reared that were in every way identical with those from galls of the other species.


Antistrophus laciniatus n. sp. 

Galls.—Individual galls are egg-shaped, from 4 to 5 mm. in length, and occur in clusters un the receptacles of the flowers of Silphium laciniatum. (Plate IX., Fig. 8.) Mr. C. A. Hart has collected a number of these gall-clusters and in his description of them says : '' They always occur in well-ripened, healthy-looking flower heads, but do not show until the weather has removed the uninfested flowerets. They are always produced in the sterile flowers of the disk, towards the center."

Antistrophus rufus n. sp.

While looking through the Laboratory collection for Cynipidae I was much interested in finding a vial containing a section of a stem of Silphiam laciniatum and a number of two species of Cynipidae bred from it. There was not the slightest indication of a gall upon the stem, and it was found that the flies had emerged from little cells in the pith exactly like the cells in the pithy substance of the galls of A. silphii^ above described. In company with Mr. C. A. Hart I visited fields where this species of Silphiiim was growing, and we found that the majority of the stems were more or less infested with cynipidous larvae, hundreds of which could, in some cases, be found in a single stem; but in no case was there any indication of the formation of a gall. An illustration of a stem containing these cells is given at Fig. 4, (PL IX). After finding the stems of Silphium laciniatum so much infested, we pushed our investigations further and found similar larval cells abundant in Silphium perfoliatum^S. terebinthinaceum^ and S. integrifolium. Whether the flies when bred from these stems will all prove to be one or the other of the two species here described cannot yet be told

Antistrophus minor n. sp. 

Bred from the same stem of Silphium as the preceding species (editor: Anitstrophus rufus) and about half as numerous.

Diastrophus scutellaris n. sp.

Gall unknown.

Antistrophus bicolor n. sp.

Gall unknown.

Aulax bicolor n. sp.

Described from two females taken in the field.

Descriptions of new Cynipidae in the Collection of the Illinois State Laboratory of Natural History