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205 Rh The present form is distinct from all other bisexual forms of echinus in having parapsidal grooves which are more or less obscured anteriorly. The galls of this form agree with the galls of the agamic form in being almost free of the projecting points found in most of the other varieties of the species.

Cynips (Antron) guadaloupensis (Fullaway)

agamic forms

FEMALE.—Head slightly wider than the thorax; antennae dark brown with the first two segments brownish rufous; thorax somewhat reduced, rufous and darker; mesonotum closely rugoso-punctate and hairy, the parapsidal grooves very fine, extending not more than halfway to the pronotum; anterior parallel lines barely indicated; the lateral lines more evident but short and fine; scutellum distinctly narrow and elongate; abdomen rufous brown and darker; wings shortened, from 0.46 to 0.80 of the body in length, with a reduced venation that is incomplete beyond the first abscissa of the radius; areolet closed; the cells without spots or blotches; length 2.0 to 2.9 mm.

GALL.—Naked, smooth and shining, from circular and disk-like to deep bowl-shaped with a flattened cover, or compressed pouch-shaped. Up to 13.0 mm., averaging nearer 5. mm. in diameter, the galls more or less regular, without spines or other projections; the surface entirely smooth and naked; the young galls purplish rose, in part leaf green, with a light purplish puberulence, the apical rim of the galls sometimes bright red; the older galls straw yellow to yellowish brown and darker, without the puberulence. The outer wall of the gall rather thin, soft and flexible when fresh, hard, crystalline and brittle when dry; with a large, centrally placed larval cell that is usually nearer the apex than the base of the gall, the cell with a poorly defined and inseparable cell wall. The gall attached by a slight, centrally placed projection, singly or in small groups, usually on the under surfaces of the leaves but sometimes on the upper surfaces; on the veins of the leaves of Quercus chrysolepis, Q. Wilcoxii, and probably all of the varieties of these oaks.

RANGE.—Known from southern Oregon to southern California and southern Arizona. Probably occurring from Washington into Lower California, Guadalupe Island, and southern Arizona, wherever Q. chrysolepis and its close relatives occur. Figure 27.

This is the Quercus chrysolepis species of the subgenus Antron. The gall is rather common on the canyon oak in the mountains of California, but the adult is represented by only a few specimens in our collections, apparently because the galls have not been collected at a season when they were