336 AMERICAN HYMENOPTERA. 



Female. — Black. Head — vertex microscopically crackled. Antenna? fourteen 

 jointed, joints one and two equal in length and size, rather large, third slender 

 and one and one-fourth as long as the first two, fourth short, ahout two-thirds as 

 long as the third, the remaining very short, the fourteenth very minute and the 

 suture, indistinct, joints one, two, three and four pale yellowish red, the remain- 

 ing dusky reddish brown. Thorax high and rounded, hardly smooth, but shin- 

 ing. Two diverging grooves from the scutellum to the base of the wings. Scu- 

 tellum finely and evenly rugose. No fova?, but a broad groove separates the 

 thorax and the scutellum, broadest in the centre. Abdomen shrunken in dry 

 specimens, but smooth and shining and vertically deeper than long. Legs pale 

 yellowish. Wings subfuscous; veins slender, distinct. Radial area open. Areo- 

 let relatively large. Body .06, antenna? .06, wings .08. 



Male. — Antenna? fifteen jointed, joints one and two rather shorter than in the 

 female, and the first, at the base, dark and shining, third long and pale yellowish 

 brown and semi-translucent, the remaining joints short and of a very dark 

 opaque brown. In no other species have I noticed the sudden transition of color 

 seen in this. Head, thorax, scutellum and the minute, long, pedicelled abdomen 

 dull shining black. Legs pale, but less so than in the female, inclining to yellow. 

 Wings as in the female. Body .06, antennse .06, wings .08. 



Five male and three female specimens. 



Neuroterus distort us n. sp. 



The galls are young branchlets of Q. bieolor, slightly enlarged at 

 the base and scarcely distinguishable from ordinary twigs. The 

 enlargements about half an inch long, leafy, polythalamous, the 

 leaves often curled and distorted, and the twig dwarfed in length 

 and turned to one sid. They are so inconspicuous that they would 

 escape notice were it not for the rosette-like cluster of leaves sur- 

 rounding them. My specimens, collected in considerable numbers 

 from a single tree, bear date May 25, 1893. The largest galls pro- 

 duced about a dozen insects. 



Male. — Except the antenna? and legs smooth, shining black. Antennse four- 

 teen jointed, joints one and two of moderate size and length, third equal to the 

 first two, fourth two-thirds as long as the third, fifth to the twelfth equal, thir- 

 teenth short, fourteenth very short, all dusky brown. Thorax high, smooth and 

 rounded. Scutellum rounded and perfectly smooth, separated from the meso- 

 thorax by a deep, shining groove. Abdomen with a slender petiole. The follow- 

 ing segments, seen laterally, form a globular disk, the length and breadth being 

 equal. Legs clear, pale brown, the middle of the femur darker but almost trans- 

 parent, and paler at the joints. Wings large, subhyaline ; veins pale, clear brown, 

 all distinct and complete and of equal size. Areolet large. Kadial area long 

 and narrow. Body .06, antennas .05, wings .08. 



Female. — Black. Antenna? thirteen jointed and as in the male, except that the 

 third is shorter and the whole a shade darker, and the abdomen is not petiolate. 

 Body .06, antenna? .05, wings .07. 



