Disholcaspis bassetti (agamic)

Disholcaspis quercusmamma (agamic)

Phylloteras rubinum (agamic)

Neuroterus niger (agamic)

Andricus foliaformis (sexgen)

Andricus nigricens (agamic)

Holcaspis bassetti, n. sp.

Gall: The gall occurs, sometimes singly, but usually in clusters about the twigs. The cluster represented at Fig. 2 was composed of 30 of these galls closely crowded together. The galls resemble very much the galls of Holcaspis duricoria Bass ([Cynips mamma Wal](https://www.gallformers.org/gall/568)) (Fig 3). The galls are very much the shape that a thick waxy material would take if dropped on the twigs and then suddenly congealed, leaved stout, test-like projections standing out from each drop. The central cell is placed low in the gall and can usually be seen protruding when the latter is broken off. Some entomologists have thought this gall to be identical with Walsh's C. mamma, but I have examined a large number of both forms and find the following points of difference, which convince me that this, if not a new species, is certainly a well marked variety:

H bassetti as compared with H duricoria, is rather larger and more irregular in outline. The teat-like projection is much heavier and longer in proportion to the size of the gall and appears to be a drawn-out portion of the substance of the gall, while in duricoria it is a small, hard pointed projection much resembling a spine in many cases, and often almost entirely wanting. In bassetti the substance of the gall is more corky and easy to cut. The central cell, as before stated, is at the base of the gall, and when the latter is removed the point of the cell can usually be seen protruding below. Before the gall is detached the central cell is situated with its greatest diameter perpendicular to the limb at the point of attachment of the gall. In duricoria the cell is situated at the center of the gall; it never protrudes from below when the gall is detached; and it always has its greatest diameter parallel with the limb at the point of attachment of the gall. The central or larval cells are also differently shaped. In duricoria the cell is egg-shaped, while in bassetti the end towards the twig is somewhat pointed, so that the cell is very much the shape of a plump apple seed with the point rounded off. 

Holcaspis duricoria

H bassetti as compared with H duricoria, is rather larger and more irregular in outline. The teat-like projection is much heavier and longer in proportion to the size of the gall and appears to be a drawn-out portion of the substance of the gall, while in duricoria it is a small, hard pointed projection much resembling a spine in many cases, and often almost entirely wanting. In bassetti the substance of the gall is more corky and easy to cut. The central cell, as before stated, is at the base of the gall, and when the latter is removed the point of the cell can usually be seen protruding below. Before the gall is detached the central cell is situated with its greatest diameter perpendicular to the limb at the point of attachment of the gall. In duricoria the cell is situated at the center of the gall; it never protrudes from below when the gall is detached; and it always has its greatest diameter parallel with the limb at the point of attachment of the gall. The central or larval cells are also differently shaped. In duricoria the cell is egg-shaped, while in bassetti the end towards the twig is somewhat pointed, so that the cell is very much the shape of a plump apple seed with the point rounded off.

Biorhiza rubinus n. sp.

Quercus alba

Galls: When the leaves begin to turn in October, subglobular juicy galls about two or three mm in diameter and rosy in color are found attached to the under side of the leaves. From a number of these galls collected in October 1887, four were selected and opened October 15 1888, from which one fully developed female cynip and three plump white larvae were obtained.

Neuroterus nigrum n. sp.

Galls: The galls are little pimples about 2 mm in diameter on the surface of the leaves and show equally well from above and below. There are usually a large number on a single leaf. The galls appear late in August but the flies do not emerge until the following summer. Few of the these galls were noticed in Michigan, but they are very common about Ames Iowa. My specimens were reared from the leaves of the burr oak, but in a number of instances I have taken galls that seem exactly similar on the leaves of the white oak, Quercus alba.

Andricus foliaformis, n. sp.

Gall. Small wart-like projections thrown out from the mid-rib on the under side of the leaves from which there grows a leafy expanse that extends on all sides like the corolla of a rotate flower. (Fig. 1.) 

Cynips nigricens n. sp. 

Galls in clusters attached to the midrib on the underside of the leaves. The galls are cone-shaped, and resemble very small galls of C. strobilana. The galls fall to the ground a little before the leaves drop in the fall. From a large number of these galls gathered in October, 1887, I obtained one perfectly developed female late in September, 1888. 

A Study of the Cynipidae