64 U. S. NATIONAL MUSEUM BULLETIN 216 



5. Yellow markings occupying narrow apical margin of second tergite (or some- 

 times lacking from this tergite), broader apical margin of third tergite, and 

 all but base of fourth tergite (figs. 183, g,h, 184,a); first tergite about 0.78 



as long as wide 4. pulchcllus Cresson 



Yellow markings occupying apical 0.4 ± of second to fourth tergites (fig. 

 184,c); first tergite about 0.70 as long as wide . . 6. vittatus, new specie 



1. Metopius (Metopius) robustus Cresson 



Front wing 11 to 14 mm. long; punctures on facial shield moderately 

 large but irregular in size, strong, their interspaces about 0.3 their 

 diameter; lower tooth of mandible small but quite distinct; punctures 

 on mesopleurum coarse, very strong, subadjacent; punctation of 

 metapleurum similar to that of mesopleurum but a little coarser; first 

 tergite about 0.68 as long as wide, in profile pyramidal above, 1.2 as 

 long as high; third tergite about 0.82 as long as wide; seventh tergite 

 of male and sixth tergite of female with a blunt median apical angle 

 which is strongly raised. 



This is the largest Nearctic species of the subgenus and it has the 

 most strongly raised first tergite. There are three subspecies, dis- 

 tinguishable on color as indicated below. 



Key to the subspecies of Metopius robustus 



1. Wings blackish; fourth tergite black with apical 0.3 white (fig. 183, c) ; range: 



Carolinian fauna 1c. robuslus robustus Cresson 



Wings light brown; fourth tergite yellow, black basally (figs. 183, a,b) ... 2 



2. Hind femur black, yellow on apical part and extreme base; second tergite black, 



yellow at apex (fig. 183, a); range: Nevada and California. 



la. robustus concinnus Cresson 

 Hind femur ferruginous, yellow on apical part and extreme base; second tergite 

 ferruginous, black at base (fig. 183, b) ; range: Kansas and Colorado. 



lb. robustus mirandus Cresson 



la. Metopius (Metopius) robustus concinnus Cresson, new status 



Figure 183,a 



Metopius concinnus Cresson, 1879, Trans. Amer. Ent. Soc, vol. 7, proc. p. xxvii; 

 cf. Type: d\ Nevada, (Philadelphia). 



Black. Face except for vertical elliptical area in center of facial 

 shield, interantennal process, side of face, scape, pedicel, palpi, stripe 

 next upper margin of pronotum, subtegular ridge, oval area beneath 

 front end of subtegular ridge (often confluent with the yellow on 

 subtegular ridge), small spot on mesopleurum next to middle coxa, 

 spot in hind part of metapleurum, apical half of scutellum, laterobasal 

 part of scutellum, postscutellum, spot at apex of second lateral area 

 of propodeum, apex of coxae, more or less of upper side of hind coxa, 

 trochanters, narrow base and broad apex of femora, tibiae, tarsi, 

 tegula, first tergite except at base, apical 0.25 (more or less) of second 



