,\HT. 20 REVISION OF THE GENUS WINTHEMIA — EEINHAED 21 



(9) WINTHEMIA POLITA, new species 



Abdomen largely polished, the basal fifth of segments 2 and 3 

 bearing thin bluish-white pollen; closely related to W. vesiculata. 

 but the scutellum and abdomen are entirely black. 



Female. — Front 0.25 and 0.26 of the head width in the two speci- 

 mens; parafrontals shining black before vertex, thinly pollinose 

 downward, sparsely haired; median stripe reddish-brown, much 

 voider than one paraf rontal before triangle ; inner and outer verticals 

 -developed but not very long; orbitals two pairs, proclinate; ocellars 

 present; lowermost frontals below middle of second antennal joint, 

 upper two bristles in each row reclinate ; sides of face silvery, sparsely 

 Tiaired along inner margins to middle or a little below; vibrissae 

 situated on oral margin; antennae black, third joint hardly twice 

 the length of second ; arista black, longer than antennae, thickened on 

 proximal fourth and slender beyond, penultimate joint short; cheeks 

 very narrow in profile about one-twelfth the eyy height, thinly gray 

 pollinose on red ground color; palpi yellow; back of head with 

 scanty pale hairs. 



Thorax shining black, sprinkled lightly with whitish pollen, 

 humeri and pleura more densely pollinose ; four narrow dark stripes 

 faintly visible in front and entirely disappearing behind suture; 

 scutellum black, lightly dusted with white pollen ; calypters with the 

 hind lobe brown on inner third, white outwardly and the margin 

 faintly yellow, opaque ; the front lobes wholly white, semitransparent. 



Abdomen black ; the hairs depressed ; first segment without median 

 marginals; second with one pair; third with a marginal row of 

 about 8; fourth covered with erect bristly hairs and bearing a 

 row of stronger bristles well before the apex; ovipositor tubular in 

 form, thick and fleshy. 



Legs black, knees reddish; hind tibiae subciliate with one longer 

 bristle near the middle ; middle tibiae with one large median anterior 

 bristle; tarsi ordinary; claws and pulvilli minute. 



Wings subhyaline with a brownish tinge near base and along 

 ■costal margin; fourth vein with a rectangular bend, beyond evenly 

 concave to costa; first posterior cell open well before wing tip; third 

 vein with two hairs at base ; no costal spine. 



Length, 6.5 to 8 mm. 



Male. — Unknown. 



Ty^e.— Female, U.S.N.M. No. 43341. 



Described from 2 specimens: 1 in the United States National 

 Museum labeled " 1950 August 15, TD 356," no locality but supposed 

 to be from Massachusetts ; the other in my collection taken at Brown- 

 helm, Ohio, August, 1920 (H. J. Reinhard). 



