230 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 109 



4. Odinia betulae, new species 



Species Avith chiefly yellow antenna, broad brown stripe on upper 

 mesopleuron, and distinct spots on the wing veins. 



Male: Chiefly gray-black, a narrow anterior margin of front, 

 antenna (except for wedge-shaped spot distad of the arista), base of 

 arista, palpus, humerus indistinctly, scutellum faintly at apex, and 

 legs in part, yellow; face and cheek silvery white on yellow gi'ound 

 color; mesonotum with two faint, irregular brown spots between the 

 fourth dorsocentral bristles, and slight bro^vning in upper angle of 

 notopleuron; pleuron with two brown stripes, one across upper meso- 

 pleuron and pteropleuron, the other including upper sternopleuron 

 and lower margin of mesopleiu'on; abdomen with brown bands on 

 first and second terga, and four rounded spots on each of terga 3 to 5, 

 the marginal bristles and many of the hairs set in small brown spots; 

 legs variably marked with brown to blackish areas, the fundamental 

 pattern approximately as described for higuttata; wing (fig. 4) with 

 strong, black-brown spots ; halter whitish yellow ; all hairs and bristles 

 black. 



Front proportionately longer than usual, appearing almost square, 

 and measuring barely wider than long, but the width at vertex twice 

 the width of an eye and half the width of the head ; orbits and triangle 

 fairly distinct, bright gray pollinose compared with the black-gray 

 of the frontaha; each orbit with a few erect black hairs on outer half, 

 and usually a few between upper orbital bristle and the verticals; 

 cheek comparatively narrow for the genus, at its widest two-fifths 

 the greatest height of the eye and 0.28 times the height of the head; 

 vibrissa and oral bristles slender ; antenna relatively small. Acrostical 

 setae in about six rows between the dorsocentral bristles. Mid tibia 

 with two apical ventral bristles, the posterior weaker than the anterior 

 and about two-thirds as long; hind femur greatly incrassate, only 

 1.8 times as long as broad, the hind tibia slightly shorter; hind tarsus 

 somewhat broadened distally. 



Female: As described for male, except as follows: Third antenna! 

 segment slightly but distinctly larger than in male; hind femur not 

 greatly incrassate; hind tarsus ordinary, not broadened distally. 



Length of body and of wing, 3.75^.0 mm. 



Holotjrpe male (USNM 64274), China, Maine, reared Mar. 31, 1948. 

 Allotype (USNM), Augusta, Maine, reared Apr. 1, 1948. Paratypes: 

 3 males (USNM), same data as holotype; female (USNM), same 

 data as allotype; male (USNM), Strong, Maine, July 14, 1947; 2 

 males and 2 females (USNM), Bingham, Maine, July 9, 1947; 1 male 

 and 3 females (USNM), Bingham, Maine, July 15, 1947; female 

 (CD A), Trinity Valley, British Columbia, July 21, 1938, K. Graham; 

 6 males and 10 females (CDA), Laniel, Quebec, June 10, 1931, June 6, 



