68 Myron Harmon Szvenk 



specific value, and these sections may be based primarily upon the 

 proportionate length of the basal joints of the flagellum. The 

 following table will contrast these forms : 



Pleura above almost entirely yellow; 9-1 1 mm. 



Joint 3 of antennae " very much shorter " than 4, less than one-half 

 as long ; legs yellow, stained with red ; mesoscutum with broad yellow 

 lateral stripes and usually two yellow lines on the disk; flagellum 

 mostly dark, antennal joint 3 contrastingly red; first abdominal 



segment very broad sulphnrafa Smith 



Joint 3 of antennae "much shorter" than 4, about one-half as long; 

 mesoscutum with broad yellow lateral stripes but no discal 

 stripes; flagellum largely dark apically (N. periviiicta) . 

 Legs yellow, stained with red ; clypeus, bases of mandibles and 

 posterior orbital margins yellow, the latter edged with reddish ; 

 mesoscutum with two broad red bands ; a red spot on pleura 

 below; first abdominal segment broader. ./'^nVfnc/o var. b Ckll. 

 Legs red, the anterior and middle femora in front and at apex, 

 a stripe on hind femora in front and a spot on hind coxae 

 above, outer face of tibiae and hind basitarsi, yellow; upper 

 part of clypeus, bases of mandibles and posterior orbital 

 margins red ; mesoscutum merely with reddish edgings to the 

 yellow lateral stripes ; a black spot on pleura below ; first 



abdominal segment narrower perivincta Ckll. 



Joint 3 of antennae " slightly shorter " than 4, about two-thirds as 

 long (iV. citrina). 

 Broad yellow stripes on sides of mesoscutum over tegulae ; disk 

 of mesoscutum red with three black lines; niesoscutellum wholly 

 yellow ; flagellum strongly blackened at end ; legs yellow, suf- 

 fused with reddish on coxae, trochanters and femora behind, 

 the coxae and posterior femora behind with black. 



ftavomarginata n. subsp. 

 Yellow of mesoscutum confined to a spot before tegulae. 



Mesoscutum wholly or largely red ; legs red and yellow, the 

 former color predominating, the hind coxae and 

 femora with much black behind. 

 Flagellum strongly blackened at end; mesoscutum red 

 with a broad median black band and black on the 

 anterior and posterior margins ; mesoscutellum wholly 



yellow semirufula Ckll. 



Flagellum entirely red ; mesoscutum wholly red ; scutel- 

 lum with two yellow spots separated by red. 



, rufula Ckll. 



6S ' 



