-iili S. FRANK AARON. 



purple and green reflections; very closely allied to dimidiatnm ; differs 

 in having the margin of the postscutellum dividing it from the following 

 punctured area on the metanotum, in the punctures, and in the base of 

 the third segment being nearly even with the apex of the second. In 

 some specimens the third segment is subconical, but this character, 

 together with the striated basin of face and the density of the abdominal 

 punctures is inconstant, and in some specimens one or more of these 

 characters approach dimidiatum. 

 Hed.ychridiuin cseruleiiiii. 



Hedychrum cccrukinn Norton, Trans. Am. Ent. Soc. vii, 239, 1879. 

 Two specimens from Dakota and Montana. The type is dark blue 

 with green and blue on the thorax, mostly purple on the abdomen, the 

 other is lighter blue with much green and little purple. On the meta- 

 notum, below and connected with the postscutellum, a median ridge, on 

 each side of which is a branching transverse ridge directed towards the 

 metasternal spines. Between the transverse ridges and the posterior 

 margin of the postscutellum are longitudinal striae, longer laterally, and 

 below these, on each side of the median ridge, a triangular, slightly 



roughened space. 



HEDVCHRU91 Latreille. 



Hist. Nat. Cr. et. Ins. 1804. 

 Occiput pro- and mesothorax with smoothed areas and sparse punctures. 



obsoletiiiu. 



No smoothed areas, strongly and closely punctured all over the head and thorax. 



Dorsum of thorax coppery red (or golden and green with red reflections in some 



specimens), contrasting with the head, metanotum, legs and abdomen, 



which are green or blue ' Ciipricolle. 



Dorsum of thorax about uniform in color, from blue and purple to emerald- 

 green, not contrasting with the other parts, and if inclining to coppery or 

 golden, the other parts have bright brassy or golden reflections. 

 As viewed posteriorly the postscutellum is rounded and connects with a me- 

 dian ridge on the metanotum; the metanotal spines have the excavation at 

 the base anterior to the black foveolse with cross striae (a great variation in 

 size, color and other minor characters, is represented in this species. See 



description) violaceum. 



As viewed posteriorly the postscutellum is followed by or extended into a 

 punctured area on the metanotum, which takes the place of the median 

 ridge; the metanotal spines have foveolse or punctures at the base anterior 



to the black foveolae: not striated continuum. 



Hedychruni obsoletuni Say, Boston Journal i, 284, 1835; Norton, 

 Trans. Am. Ent. Soc. vii, 237. 



H. Zimmermanni Dahlb., Hym. Eur. ii, 61, 1882. 

 Four specimens from Illinois and Pennsylvania (Iowa, Say). Front 

 closely and vertex loosely punctured, green ; occiput pro- and mesothorax 

 polished with small, very sparse punctures, purple and blue ; sides and 



