AMERICAN IIYMEXOPTERA. 59 



Head metallic green; mouth and its surroundings yellow, which color is 

 more extended in the 9 than in the"^; scapus of the antennae yellow, the rest 

 black; front and vertex microscopically sculptured. Thorax yellow, except 

 the scutelhun, which is green, and a shining green spot on the jdeurre, above 

 the middle cox£e; besides, in the *£ the upper part of the mesotliorax is green, 

 which color also somewliat encroaches on the prolhorax; in the 9 this color of 

 the back is less extended, more faint, and has a somewhat bluish tinge. Me- 

 tathorax green in the'^; yellow, with a bluish tinge, in the 9- The scutellum 

 is very minutely sculptured and has, also, some scattered and indistinct punc- 

 tures which can only be perceived under a high magnifying power. Abdomen 

 yellow, more or less tinged with brown on its upper side at the base, and on its 

 latter half; the basal brown space has a metallic green reflection ; the apical 

 one is somewhat bronzed; both have more or less extent in different specimens, 

 so that the yellow interval between them is more or less narrow; the undei'side, 

 which is usually yellow, is also more or less encroached upon by the brown of 

 the upper side ; ovipositor brown, about equal in length to the body without 

 the head ; feet yellow, tarsi whitish ; onychia brown : wings hyaline : costal vein 

 slender. 



One S and two 9 specimens, reared from the gall of Laxiopfrra vilis, 

 O. S., on the wild grape, near Washington, D. C., (compare my paper 

 on Cecidomijia in Loew's 31onographs of N. Am. Diptera, p. 201.) 



2. C. dura, n. sp. 



From the gall of Di'phsis canjx (1. c. p 191), I have reared a sin- 

 gle male specimen, larger than the S of the preceding species, as it 

 measures 0.1 — 0.11, but resembling it in the distribution of the colors, 

 except that the head is altogether green, there being no yellow round 

 the mouth, and that the prothorax is green above, and yellow only 

 below. The costal vein of the wings is much stouter. 



V 3. C. advena, n. sp. — Greenish blue, head anil thorax punctured, femora 

 greenish or bluish ; tibire of the 9 yellow, the hind ones infuscated in the mid- 

 dle; tibiae of the 'J, all infuscated; tarsi yellow, whitish at the base; brown at 

 the tip. -J, about 0.09; -J, 0.12— 0.13; ovipositor 0.11— 0. 12 of an inch long. 



Head more greenish on the face, more bluish on the front, with rather deep, 

 moderately dense punctures; scapus of the antennae reddish yellow; first joint 

 of the flagellum greenish, the others black; mouth brown; thorax greenish- 

 blue or bluish-green, covered, rather densely, with deep, pit-like punctures, 

 extending also over the scutellum. The posterior portion of the scutellum is 

 separated by a fine, transverse, impressed line, is more greenish and more 

 smooth than the remainder, being only covered with dense, short, microscoi)ic 

 striae. Metathorax with a quadrangular, smooth space in the middle, divided 

 in two by a longitudinal imi)ressed line; its sides with irregular irregualities. 

 Pleurte greenish or bluish. Fore coxae greenish, with very delicate, micro- 

 scojjic transverse striae; middle and hind coxae usually blue; the latter finely 

 and den.--ely punctured. Femora blue or green; the anterior ones more incli- 

 ning towards the green, the posterior ones towards the blue; their inner side is 

 always brown ; their tip yellowish. Tibiaj of the % brown in the middle, yellow 

 at the extreme base and at the tip; the front ones with a greenish lustre ; tibiae 



