OF WASHINGTON, VOLUME XIV, 1912. 151 



sides straight and converging posteriorly. Wings colorless, distinctly 

 broader in basal than in apical half, slightly narrowed at middle, not closely 

 fringed (the posterior margin with only about 52 hairs), subapical fringe 

 double for about nine hairs. Legs rather stout, fore tarsus with a short, 

 stout, acute tooth. 



Abdomen little, if any, broader than pterothorax, broadest toward base, 

 thence rounded gradually to base of tube. Tube about 0.6 as long as head, 

 2.3 times as long as basal width, about 1.8 times as wide at base as at apex, 

 sides straight. Lateral bristles of moderate length, knobbed, yellowish, 

 two pointed pairs at apex of segment 9 longer; terminal bristles about as 

 long as tube, brown. 



Measurements of holotype: Length 1.64 mm.; head, length 0.288 mm., 

 width 0.234 mm.; prothorax, length 0.139 mm., width (inclusive of coxae) 

 0.352 mm.; mesothorax, width across fore margin 0.396 mm.; metathorax, 

 width across hind margin 0.354 mm.; abdomen, width 0.414 mrn.; tube, 

 length 0.174mm., width at base 0.075 mm., at apex 0.042 mm. Antennal 

 segments: 1, 33 M; 2, 54 ; 3, 78 n; 4, 75 M ; 5, 69 M ; 6, 54 M ; 7, 48 M ; 

 8, 31 n; total length of antenna, 0.44 mm., width at segment 4, 0.035 mm. 



Female (forma brachyptera). Apparently identical with the winged 

 form in all points of structure; pterothorax perhaps slightly smaller and 

 weaker. 



Male (forma brachyptera). Length about 1.3mm. Head very slightly 

 longer than in female, about 1.3 times as long as wide; postocular bristles 

 nearly half as long as head, invariably bent at middle and curving forward. 

 Femora and tibiae swollen; tarsal tooth large, nearly straight, about two- 

 thirds as long as eye. Prothoracic bristles scarcely longer than in female. 



Described from 13 females (of which four are brachypterous) 

 and 8 males, all from Illinois, as follows: Cherry Valley, 

 August 14, 1909, Hugh "Glasgow, 2 brachypterous females, 

 "in old mines of Scolytids"; Desplaines, September 5, 1908, 

 J. J. Davis, 1 male under bark on apple tree; Dubois, October 

 1, 1908, L. M. Smith, 1 brachypterous female on hickory 

 branch; Dubois, July 13, 1909, C. A. Hart., 1 male on hack- 

 berry; Grand Tower, June 30, 1909, C. A. H., 1 macropterous 

 female on locust; Odin, September 29 V 1908, L. M. S., 1 

 brachypterous female on hackberry; Parker, July 14, 1909, 

 C. A. H., 1 macropterous female on willow; "Marion, 1909, 

 reared from galls on twigs of pin oak (Quercns pains Iris 

 Muench.), taken July 18 by W. P. Flint, adults found August 

 18 in breeding cage by James Zetek, Exp. 4499 111. State Lab. 

 Nat. Hist.", (5 macropterous females and 5 males; Southern 

 Illinois, C. A. H., from elm covered with trumpet creeper 

 (Tecoma rad leans (L.) Juss.). 



Type locality : Marion, Illinois. 



This is an anomalous member of its genus, and may easily 

 be known by the rounded vertex, the peculiarly shaped head 



