NORTH AMERICAN HYMENOPTERA. 207 



the cheeks ; eyes as in the male ; thorax ovate, robust ; the interme- 

 diate and posterior tibiae are exteriorly armed with spines ; abdomen 

 ovate, having the basal segment small, campanulate and subsessile 

 with the second segment. 



The species of this genus are more densely pubescent than any in 

 the MutilMse, often being richly adorned with golden or silvery 

 pubescence and beautiful coloring and markings. 



The species are quite numerous, and may be divided into two divi- 

 sions and subdivisions, viz. : 



DIVISION I. 



First abdominal segment small, more or less nodose and constricted 

 at apex, as in figures 11 and 12. 



Fig. 11. Fig. 12. 



This may be again divided into two subdivisions : 



Subdivision I. 



Head broad and quadrate behind the eyes, mandibles broad ; neu- 

 ration of anterior wing as represented by figure 13. 



Fig. 13. 



Sphserophtlialma scseTa Blake. 



Male. — Black • head rounded, as wide as the thorax, closely punctured, space 

 above and between the eyes rufo-ferruginous, with short erect hairs ; antenna- 

 black, the scape finely punctured ; eyes round, prominent ; thorax subquadrate. 

 narrowed posteriorly, mesothorax elevated, metathorax abruptly rounded, 

 coarsely reticulated ; wings ample, fuliginous, marginal cell elongate ovate, 

 slightly rounded at tip ; two distinct submarginal cells, first moderately long 

 and narrow, second about half as large as the marginal, receiving the first re r 

 current nervure a little before the middle ; legs black, clothed with scattered 

 black hairs, posterior tibiae armed with a single spur ; abdomen ovate, basal 

 segment elongate, closely punctured, thinly clothed with black hairs; second 

 segment pale ferruginous, with scattered hairs of the same color, shining, finely 



