J. C. HUTSON 225 



frons not so deeply sunken as in cyaneum, distinctly punctured, moderately 

 covered with erect black hairs; a fine silvery pubescence clothing nearly all the 

 sunken area of the frons; ocelli with distinct grooves at outer bases; vertex 

 sparsely punctured, erect hairs rather few, finer hairs whitish; genae distinctly 

 punctate, moderately dense hairs interspersed with fine sericeous vestiture; 

 inner margin of compound eyes distinctly concave near upper end, gradually 

 convergent towards clypeus for lower half, eyes usually more approximate 

 below than above; antennae with scape black with metallic blue green reflections, 

 a number of rather short hairs mostly on inner surface, finer sericeous hairs 

 vary from silvery to pale brown, pedicel with a few small hairs on inner sur- 

 face; flagellum dull black with a dense covering of fine recumbent hairs giving 

 it a black to greyish appearance according to the light ; first segment of flagellum 

 distinctly narrower proximally and shorter than second, remaining segments 

 only very slightly narrower proximally, last segment not cut off truncately as 

 in cyaneum, but tapering to a blunt point; mandibles of medium length with one 

 rather wide tooth on inner margin not reaching to the tip; a row of four or 

 five stout hairs on outer side and about twice that number on inside. 



Thorax. — Anterior surface of collar -with a steep upward slope to the some- 

 what acute crest; and distinctly rugose at anterior end, dorsal lobes small and 

 separated by a shallow depression; punctures small and scattered, pilosity finer 

 and smaller than in cyaneum, sericeous hairs pale to whitish; median depression 

 on sides of collar not ending abruptly in a fovea but continued above to the 

 groove between neck and collar; prothoracic lobe with a fringe of pale brown 

 hairs; median depression on mesonotum faint or absent; depressions at pos- 

 terior sides of mesonotum not as strongly marked as in cyaneum; scutellum may 

 have a slight median depression; posterior margin of lateral pits fringed with 

 silvery white hairs; postscutellum with small punctures, posterior margin wnth a 

 few white or pale hairs; median segment with anterior margin of dorsum flanged, 

 posterior margin more pointed than in cyaneum, whole surface of shield trans- 

 versely striated or rugose and without median depression, hairs rather delicate, 

 whiter at sides along the outline of dorsum than in the center; posterior end of 

 dorsum sloping more gradually to hinder margin than in cyaneum, surface with 

 irregular striations, punctures confluent, numerous dark hairs; stigmatal 

 groove not well marked, sides of dorsum strongly punctate behind, smaller 

 punctures anteriorly; mesopleura and mesosternum with deep punctures and 

 long black hairs; metapleura distinctly punctate except along metapleural 

 groove which is somewhat bare and shiny, lateral oblique depression shallower 

 than in cyaneum; petiole slightly shorter and more slender than that of cyaneum, 

 punctures and hairs scattered, chiefly on basal half, finely sericeous mostly on 

 upper half of distal end. 



Abdomen medium to small, rather ovate, paler blue than in i:yancum, shin- 

 ing, with minute white recumbent hairs scattered evenly over the dorsal sur- 

 face, first three dorsal segments without dark hairs, fourth and fifth with a few 

 scattered punctures and dark hairs; sixth or terminal segment with hairs near 

 posterior margin, bare along median line, dorsal segment may almost cover 

 ventral; tip of abdomen a little more slender than in cyaneum; ventral segments 



TRANS. AM. ENT. SOC, XLV. 



