220 GEO. H. HORN, M. D. 



Occurs ill the entire northern portion of the continent as far south 

 as Pennsylvania, tlience westwardly extending in the western plains 

 to Texas and Arizona, and on the Pacific slope from Alaska to 

 Mexico. 



2. II. clialybea Illig. — Oval, of moderately robust facies, color usually 

 uietHllic shining blue, rarely cupreous or greenish. Antennae half as long as the 

 body, piceous, the basal half with metallic lustre, joints 2-3-4 giadually longer. 

 Head smooth, slightly roughened near the eyes, frontal carina rather acute, the 

 tubercles small, oblique. Thorax a little more than half wider than long, nar- 

 rowed in front, sides arcuate, margin narrow, slightly thickened in front, disc 

 convex, the aute-basal impressed line rather deep and extending from margin to 

 margin, surface with extremely minute scattered puuctures. Elyti'a scarcely 

 wider at base than the thorax, humeri rounded, umbone moderately prominent, 

 smooth, limited within by a slight depression, surface sparsely punctate, nearly 

 smooth near apex. Body beneath and legs blue-black, moderately siiining, ab- 

 domen sparsely punctate. Length .16— .20 inch. ; 4—5 mm. 



The variations from the usual blue color in this species seem very 

 rare ; for a cupreous specimen from Florida and a greenish one from 

 Detroit I am indebted to Mr. E. A. Schwarz. 



The thoracic impressed line is quite constant in its depth and ex- 

 tent, consequently there will be no great difficulty in distinguishing 

 this from the other robust species, californica, obliferata and vlcaria, 

 all of which have the impression feeble, although in some of carmata 

 it is moderately deep and nearly entire. The latter species has the 

 thorax distinctly narrower than the elytra and a more prominent 

 head. 



The next species is the only other one with the impression entire, 

 but this is smaller, more depressed and more evidently punctate. 



Occurs from New England States and Michigan to Florida and 

 Texas. 



'■i. H. nana tJrotch. — Oblong oval, convex, metallic blue or bluish green, 

 shining. Antennae as long as half the body, slender, joints 2-4 equal in length, 

 outer joints piceous, basal four joiuts pale. Head smooth, frontal carina moder- 

 ately prominent, acute, tubercles feeble and flat Thorax one-third wider than 

 long, narrowed at apex, sides arcuate, disc convex, sparsely indistinctly punc- 

 tate, the ante-basal impression deep, sharply impressed and extending from side 

 to side. Elytra scarcely wider at base than the thorax, humeri rounded, umbone 

 scarcely prominent, a distinct depression at base within it, disc convex, the 

 punctuation relatively very coarse, deep and close, but smoother toward the 

 apex. Body beneath jiiceous, shining ; abdomen sparsely punctate. Legs brown- 

 ish testaceous, posterior femora piceous. Length .08 inch. ; 2 mm. 



The last ventral of the male has a deep semi-oval inqji-ession, 

 which extends nearlv half the length of the segment. 



