AMERICAN HYMENOPTERA. 5 



knees, anterior femora within, four anterior tibiae, base of their tarsi more or 

 less, and base of posterior tibiae pale; abdomen short, broad-ovate, depressed. 

 Length .23 inch. 



Hah. — Nevada, (Morrison). 



Xeinatus iridescens.^'J, . — Narrow, shining, black; clypetis, labrura 

 and palpi, whitish; antennae subrobust, slender at tips, three basal joints of 

 flagellum of nearly equal length ; a shallow basin on vertex, converging above 

 and enclosing the lower ocellus; posterior angles of prothorax and tegulae 

 whitish ; wings hyaline, iridescent, nervures and stigma black, neuration much 

 as in vicinal is ; legs dull whitish, coxae at base, and four anterior femora except 

 base and apex fuscous; posterior femora except tips of their tibiae, their tarsi 

 entirely, and tips of four anterior tarsi, black; posterior tiljiae deeply grooved 

 on outer side towards apex ; abdomen elongate, narrow, depressed, ridged down 

 the back. Lengtii .23 inch. 



Hub. — Nevada, (Morrison). This may be the S of l<ttus. 



fiemsttus parvus. — 9- — Small, piceous; spot between antennae, clypeus, 

 labrum, mandibles except tips, spot beneath eyes, and palpi, white; upper 

 posterior orbits sometimes obscurely pale; antennae more than half the length 

 of body, slender, three basal joints of flagellum of nearly equal length; pos- 

 terior angles of prothorax and tegulae, whitish; wings hyaline, slightly yel- 

 lowish, iridescent, nervures and stigma pale brownish, base of stigma and 

 nervures at base of wing, whitish, second submarginal cell receiving first 

 recurrent nervure about one-fourth from base, and the second about one-eighth 

 from tips, third submarginal cell about half the length of second, longer than 

 broad; tips of coxae, trochanters, sides of femora, knees, most of tibiae and base 

 of four anterior tarsi, dull whitish; spot on outer middle of tibiae and tijjs of 

 posterior pair black; abdomen short, robust, more or less compressed at tip. 

 Length .15 inch. 



Hub. — Nevada, (Morrison). 



Neniatiis palliveiitris. — 9- — Black; clypeus obtusely emarginate; 

 labrum and palpi pale; antennae two-thirds the length of the bod}' slender, 

 three basal joints of the flagellum of nearly equal length; posterior angles of 

 prothorax and tegulae, white ; wings hyaline, iridescent, nervures and stigma 

 black or fuscous, neuration as in vicinalis ; tips of coxae, trochanters, four 

 anterior femora in front, knees, four anterior tibiae, most of their tarsi, pos- 

 terior tibiae at base and line within, all yellowish-white; abdomen subcom- 

 pressed, a little longer than head and thorax, lateral margin of the segments, 

 apical middle of first, apical segment and the venter entirely, white. Length 

 .25 inch. 



ILib. — Nevada, (Morrison). 



Nematiis riiralis. — 9- — Black, shining; face, spot between antennae, 

 cheeks, line across the head behind the ocelli, sometimes more or less inter- 

 rupted medially, clypeus, labrum, mandibles except tips, palpi, most of pro- 

 thorax, tegulae, sometimes two spots at base of scutellum, most of legs, venter, 

 extreme sides and apex of abdomen above, luteous or dull yellowish ; antennae 

 more than half the length of the body, slender, three basal joints of the 

 flagellum of nearly equal length; wings hyaline, nervures black, costal nerve 

 and stigma luteous or pale fuscous; second submarginal cell receiving the first 



