Femuros perfectum comb. rest.

Femuros perfectum, n. sp.
Agamic form

Gall. — Fairly large, nearly globular or slightly elongate or flattened, with the exceedingly small cavity in the upper half of the gall almost completely closed by very thick and solid walls, although a central pucker at the apex of the gall still indicates the opening to the cavity; cavity never wider than larval cell, often narrower; outside of gall silvery gray to purplish brown, conspicuously covered with a purplish-white bloom; up to 16.0 mm., averaging nearer 13.0 mm. in diameter, never more than 13.0 mm. in length.

Host. — Quercus macrophylla [magnoliifolia], the largest-leaved white oak of southwestern Mexico.

Range. — Guerrero; Chilpancingo, 6 W3 40007 (types). Tierra Colorado, 14 N, 3200? (galls). Probably restricted to a portion of the state of Guerrero, in southwestern Mexico.

Life History. — Adults: May 10, July, 8, in the first year after the development of the gall.

This insect, from the state of Guerrero in the southwestern corner o’ Mexico, is closest to F lusum. The galls of the two species are strikingly distinct — an interesting instance of divergent modifications of a single basic plan. See lusum for a comparison of the galls of the two.