56 PROCEEDINGS OF THE NATIONAL. MUSEUM vo;.. C8 



ZOPHEROTERAS SPHAERULA, new species 



Agamic female. — Eeddish-brown ; antennae infuscated distally, 

 abdomen posteriorly black. Head coriaceous; from above much 

 broader than thorax, length in axial line to breadth as 18 : 55, oc- 

 ciput concave, cheeks ample but scarcely broadened behind eyes; from 

 in front broader than high, facial area one and nineteen hundredths 

 times as broad as high, malar space .3 eye with shallow groove, an- 

 tenna 14-segmented, length as (scape) 15 (width 8) :7(6) :20(4.5) :15: 

 13:12:11:10:9:9:8:8:7:12(5). Sides of pronotum coriaceous 

 and protruding. Mesonotum coriaceous. Mesoscutum .49 width of 

 head with two distinct percurrent grooves well separated behind, 

 with a hump behind middle when seen in profile. Scutellum reach- 

 ing .6 way back to petiole with a large smooth deep laterally 

 bounded pit at base in which is a slight septum, the disk narrow, 

 elevated, and somewhat pointed behind when seen from above, 

 rounded and knoblike in profile. Sides of metanotum almost hori- 

 zontal. Carinae on propodeum curved outward, well separated 

 above, enclosing the base of the reticulate neck. Mesopleura coria- 

 ceous. Wings wanting. Legs well developed. Hind tibia longer 

 than tarsus, whose segments are as 33 : 11 : 8 : 6 : 13, claws large, 

 simple. Abdomen large, attached to thorax near end of its short 

 axis so that in side view it is elliptical in outline and obliquely 

 placed, length to height to thickness as 39 : 29 : 15, lengths of tergites 

 along dorsal margin as 16 : 7 : 5 : 5 : 4 : 1, dorsal edge Imif elike behind 

 second. Ventral valves oblique, tips exserted, tip of ovipositor 

 .strongly curved. Ventral valve slender, tapering, horizontal, in side 

 view five times as long as broad. Using width of head as a base 

 the length of mesonotum ratio is .7, antenna 3.0, ovipositor 7.1. 

 Length, 2.0-3.5 mm. Average of 75 measured specimens, 2.44 mm. 



Tyl)e.—C2^.. No. 27202, U.S.N.M. Type and 29 paratypes. Para- 

 types in American Museum, Field, Stanford, Harvard, and Phila- 

 delphia Academy. 



Host. — Quercus maxima, red oak. 



Gall. — Spherical or slightly ellipsoidal, not depressed, found in fall 

 on both upper and lower surface of leaf attached to a vein, singly or 

 3-4 in a row, about 3 mm. in diameter, greenish or yellowish-green 

 often tinged with red above, dropping to the ground before the 

 leaves. Monothalamous, fleshy, apparently solid when fresh, the 

 larval cavity scarcely visible. 



Hahitat, — Type locality, Evanston, 111. The galls were also seen 

 at Wilmette, Ravinia, and Moline, 111.; Medina, N. Y. ; and at 

 Bluemont, Va. 



Biology. — Galls collected on ground under two large forest trees 

 on the bank of the Chicago River four miles west of Evanston on 



