11 
well separated, cup-shaped; funicle joint 1 about as long as pedicel, 
but longer and narrower than succeeding joint; joints 1-4 each slightly 
wider than preceding joint; club ovate, as long as two preceding funicle 
joints together. Abdomen longer than thorax, shining, with very faint 
sculpturing ; penultimate and antepenultimate segments with abundant 
white pile, which also occurs on the pygidium as well as the head and 
thorax; spur of stigmal club given off just before tip and reaching 
farther toward apex of wing than does tip of club; pronotal spot lack- 
iug, pronotum uniform jet black, as is the rest of the body; the place 
ordinarily occupied by the yellowish pronotal spot somewhat sunken, 
has a finer sculpture, and is lacking in the white pile found elsewhere 
on the thorax. All legs uniform dark honey-yellow except coxe, which 
are black; scape dark honey-yellow; wing veins light brownish-yellow. 
Male.—Closely resembles female. Antenne long and stout; scape 
slightly expanded below; pedicel small, globose; funicle joints strongly 
arched above, not constricted in middle, markedly pedicellate, and each 
with two half whorls of long hairs; funicle joint 1 nearly twice as long 
as 2; 2, 3, 4, and 5 subequal in length; club elongate, pointed, as long 
as two preceding funicle joints together. Punctation somewhat less 
distinct; legs black, except tarsi and tips of femora and tibiew, which 
are yellow; petiole stout, as long as first abdominal joint. 
Described from 5 females and 10 males captured April 20, 1891, by 
Albert Koebele, in the upper part of Shepherd’s Canyon, Argus Moun- 
tains, California, upon Hriocoma cuspidata. ‘The insects were collected 
in numbers at rest upon the upper part of the plant just before dusk. 
Upon examining the grass stalks Mr. Koebele found that they contained 
holes from which the Isosomas had apparently emerged. 
Isosoma bromi n. sp. 
Female.—Length, 3.4 mm.; expanse, 5.6 mm. Head and thorax 
densely umbilicate-punctate, punctations rather finer and closer than in 
preceding species; pronotal spot wanting; abdomen without a trace of 
sculpture, not longer than thorax, but more swollen than in preceding 
Species; mesoscutellum and metanotum as with californicum, except 
that the metanotum each side of median groove is not so coarsely pune- 
tate; claw of stigmal club strongly curved; front coxze honey-yellow, 
middle and hind coxe black; front femora and tibiwe honey-yellow, 
middle femora honey-yellow, tibize darker, hind femora and tibize dark 
brown, yellowish at joints. 
Male.—Length, 3 mm.; expanse, 5.4mm. Antenne as with califor- 
nicum, except that joint 1 of funicle is less than twice as long as 2, and 
is regularly furnished with long hairs not arranged in whorls. Petiole 
slenderer than with preceding species, little longer than cox, and not 
as long as first segment of abdomen. 
Described from 2 females and 1 male reared from Bromus ciliatus, in 
May and August, 1887, at Los Angeles, Cal., by Albert Koebele. 
