AMERICAN HYMENOPTERA. 277 



specimens. A large roljust species, easily recognized" by the two large 

 yellow spots on the first abdominal segment above, each spot occupying 

 nearly the entire lateral surface, and sometimes almost meeting on the 

 posterior middle. 



Nyssoii auriiiotus Say, Bost. Journ. Nat. Hist, i, p. 368.— " Body black, 

 punctured; head before with a slight yellowish sericeous reflection; mandibles 

 piceous; collar with an obscure golden margin, terminating in a spot; nietathorax 

 with a golden spine each side, in a golden spot: wings dusk}'; tergum on the 

 posterior edges reflecting whitish ; at base of the first segment obscure golden 

 sericeous; posterior margins of the first, second and third segments each with 

 a yellow band widely interrupted in the middle, the anterior one largest; feet 

 honey-yellow, thighs black at base. Length three-tenths of an inch. 



" Inhabits Indiana." 



Not identified. The description given above seems to refer to a much 

 smaller species than the jireceding {plagutfus). In some respects it 

 agrees with small specimens of Farunysson texamts, but not sufiiciently 

 well to render their identity certain, as that species has several jjrominent 

 characters which Say would scarcely have overlooked. 



Two $ specimens from Illinois, closely related to plagiatus, but 

 smaller (.40 inch), and with a yellowish band at apex of the three basal 

 segments of the abdomen above, rather widely interrupted in the middle, 

 that on the first segment much broader than the others, but not dilated 

 laterally, may belong to this species, or else to sequaiis Patton, should 

 that prove to be distinct from aurinotux. 



Nysson sequalis Patton, Can. Ent. xi, p. 212.— " '^ .—Length 8.5 mm. 

 Black; mandibles, scape, first joint of flagellum beneath and spot on second joint, 

 testaceous; tips of mandibles and spot on scape above, piceous; spot on scape 

 beneath, uneven line on collar connected on each side with tubercles and inter- 

 rupted in middle, tubercles excepting a piceous dot, transverse spot on anterior 

 portion of scutellum, spines of metathorax, spots on anterior and posterior eoxre 

 and at tip of four anterior femora beneath, and interrupted bands on four basal 

 segments of abdomen, on fourth segment very narrow and that on first segment 

 broadest and none of the bands dilated at sides, yellow ; legs fulvous, coxse and 

 a spot on femora within black. Body clothed with a verj' fine pubescence, that 

 upon face, sides of dorsal face of metathorax and margins of abdominal segments 

 longer and distinct, apex of abdomen with a fringe of curved bristles. Wings 

 brown ; third submarginal cell with a short side ui^oii the marginal, submedian 

 cell of posterior wings extending beyond the median cell upon the externo-medial 

 nervure. Body strongly punctured, the punctures somewhat confluent upon pleura 

 of mesothorax and upon the two apical segments of abdomen and more sparse 

 upon the other abdominal segments. A slight depression on each side of disk 

 of mesothorax and an impressed median line extending upon the disk from the 

 prothorax. Posterior portion of scutellum, the postscutellum and base of meta- 

 thorax longitudinally rugose, the rugse slightly connected by transverse rugte ; 

 postscutellum elevated into a transverse ridge; sides of metathorax coarsely re- 



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