100 XT. S. NATIONAL MUSEUM BULLETIN 216 pabt 3 



2. First tergite with a basolateral tooth; head of both sexes entirely black; meso- 



scutum of female mat and with fine weak punctures. 



1. affabilis (Provancher) 



First tergite without a basolateral tooth; head usually marked with white, at 



least on the clypeus, cheek, or frontal orbit, or if entirely black then the 



mesoscutum polished and with moderately large, strong punctures ... 3 



3. Metapleurum and propodeum entirely black; face of male with white mark- 



ings, or sometimes entirely white 8. notata (Provancher) 



Metapleurum and propodeum partly or entirely ferruginous, or in some males 

 of A. nlbicollaris dypeata these are entirely black, but in this subspecies the 

 face is entirely black, which differentiates it from male of A. notata . . 4 



4. Punctures on mesoscutum fine and weak; mesoscutum strongly mat. 



2. byrsina, new species 

 Punctures on mesoscutum coarse and strong; mesoscutum polished or mat . 5 



5. Mesoscutum with a central white spot; clypeus in profile very strongly con- 



vex, its apical margin without a trace of a tooth; hind basitarsus entirely 



white. Female unknown 6. barberi, new species 



Mesoscutum without a central white spot; clypeus in profile weakly or mod- 

 erately convex, its apical margin with a weak or very weak median tooth; 

 hind basitarsus usually not entirely white 6 



6. Mesoscutum somewhat mat and strongly punctate; male with temple mostly 



white and the seventh tergite without a white spot; front wing of female 

 with a postmedian cloud and the wing apex infuscate. 



5. nubecula, new species 



Mesoscutum polished and strongly punctate; male with temple mostly white, 



ferruginous, or black, if white then the seventh tergite with a white spot; 



front wing of female uniformly subhyaline 7 



7. Dorsolateral carina of first tergite strong and sharp between its spiracle and 



base; temple entirely black 7. albicollaris (Cresson) 



Dorsolateral carina of first tergite indistinct or obsolescent between its spiracle 

 and base; temple partly or entirely white or ferruginous on its lower half . 8 



8. Apical transverse carina of propodeum rather evenly curved or only weakly 



bowed forward at the middle (so that median forward extension of apical 

 area of propodeum is not more than about 0.25 as long as wide) ; hind basi- 

 tarsus of male brown with not more than its apical 0.15 white. 



3. linnae, new species 



Apical transverse carina of propodeum strongly bowed forward at the middle 



(so that median forward extension of apical area of propodeum is about 0.4 



as long as wide); hind basitarsus of male fuscous with its apical 0.4 to 0.7 



white 4. gracilis (Provancher) 



1. Aritranis a£fabilis (Provancher), new combination 



Cryptus affabilis Provancher, 1877, Naturaliste Canadien, vol, 9. p. 13; ?. Type: 

 9, Que. (Quebec). 



Front wing 3.2 to 5.4 mm. long; clypeus weakly convex, its apex 

 weakly reflexed, with a moderately strong, blunt, median tooth; thorax 

 moderately elongate; mesoscutum mat, its lateral lobes mostly sub- 

 polished, in the male its punctures of moderate size and very weak, in 

 the female its punctures small and rather weak; apical carina of pro- 

 podeum strong throughout, in female weakly produced sublaterally, 

 strongly[sinuate,^its median part bowed forward; areolet of moderate 



