NORTH AMERICAN HYMENOPTERA. /O 



in diameter. The dry galls are exceedingly hard, and they bear a 

 very close resemblance to those of A. dcatrieula, though the scar or 

 indentation invariably found in that species is wanting. The larval 

 cells are not .separable from the solid woody fibre around them, and 

 they all radiate from a common centre. 



My galls, collected by Mr. Howerton in New Mexico, have pro- 

 duced no males, but I do not look upon this as an agamous species. 



Gall-flies. — Female. — Head and thorax very dark, brownish red, approaching 

 black ; antennae short, 1.3-jointed, the first and second joints rather small and 

 short, third hardly longer than the two preceding taken together, fourth not 

 quite as long as the third, fifth to the twelfth subequal, thirteenth one- fourth 

 longer and showing in a favorable light a dark ring near the tip hardly distinct 

 enough to be called a suture; mesothorax with an exceedingly fine reticulation 

 and a few short, scattered hairs, parallel lines reach half way from the collare 

 to the scutellum, these and the parapsidal grooves and the short lines over the 

 base of the wings are present, but very narrow; scutellum rather long, pointed, 

 finely rugose, but fovete large, shallow and smooth. Abdomen shining yellowish 

 brown, lightest anteriorly, seco!id segment very long and deep, and nearly con- 

 cealing the remaining ones. Legs light yellowish brown, except the posterior 

 pair, which are much darker; ungues simple. Wings hyaline, veins slender and 

 mostly colorless, areolet present, but indistinct, radial area open. Length : body, 

 .10 inch.; wings, .12 inch.; antennae, .08 inch. 



4. A. (Callirhytis) ruginosus n. sp. 



Gall. — A hard, round knot, nearly an inch in diameter, near the 

 tip of a slender twig of Q. (virens?) The surface rough and black- 

 ened and deeply and irregularly fissured, probably by drying, with 

 several holes made by the escaping insects. Polythalamous, the walls 

 of the numerous larval cells not separable from the firm, but rather 

 open cellular tissues around them. This gall resembles those of A. 

 Suttonii, but is much more rough, and is entirely destitute of woody 

 fibre. 



Sent me by Mr. Howerton from New Mexico. Five gall-fiies 

 reared ; all females. 



Gall-flies. — Head black, very broad behind the eyes, breadth twice its depth, 

 vertex rugose ; antennee long, slender, yellowish browu to dusky towards the 

 end, fourteen joints, first abruptly clavate, second not thicker in the middle than 

 at the ends and nearly as long as the first; third one-half longer than the two 

 preceding ; fourth to the eighth gradually shorter, remainder equal. Thorax 

 black, mesonotum roughly pitted and wrinkled, and more deeply posteriorly ; a 

 few short, white hairs towards the scutellum; median line reaches half way to 

 the collare, and two parallel lines half way to the scutellum : parapsidal 

 grooves entire; these and the lines over the base of the wings present, but quite 

 obscure; scutellum very roughly pitted and wrinkled, two large, rough pits 

 (fovese) at the base, and a smaller intermediate one. Abdomen smooth, shining, 



