OP NATURAL HISTORY. 773 



slight inequality or impressed transverse line, near the middle : 

 feet dark piceous ; tarsi and knees somewhat paler. 

 Length over two-fifths of an inch. 



8. H. LABRosus.— 9 Greenish; tergum purplish, segments 

 jnargined with blackish. 



Inhabits Mexico. 



Body green, with a purple reflection : antennae black : nasus 

 at tip blackish : labrum black, much elevated at the middle of 

 the tip ; the elevation grooved before ; mandibles black, tinged 

 with piceous at tip : wings hyaline, slightly tinged with fuligin- 

 ous; nervures fuscous: metathorax [395] with the including 

 line of the posterior disk, prominent only towards the petiole : 

 tergum darker purplish than the thorax; the broad posterior 

 margins of the segments, blackish : feet, purplish and blue : 

 tarsi blaekish-piceous. 



Length about two-fifths of an inch. 



About the size of the preceding, from which it difiers mate- 

 rially in color, and in the sculpture of the metathorax. 



4. H. PURUS. — Green ; first recurrent nervure confluent with 

 the dividing nervure of the second and third cubital cellules. 



Inhabits United States. 



9 Body green, polished, tinged with brassy or cupreous : an- 

 tennae black : labrum and mandibles piceous, the latter sometimes 

 almost honey-yellow : metathorax at base lineated ; no distinct 

 posterior disk, but the groove is well impressed, and there are 

 often near the petiole, a few, obsolete, raised, converging lines : 

 wings hyaline, very slightly dusky at tip ; nervures brown ; radial 

 nervure fuscous ; stigma pale yellowish ; second recurrent ner- 

 vure exactly uniting with the tip of the dividing nervure of the 

 second and third cellules : tergum obviously varied with brassy ; 

 posterior slender margins of the segments dark purplish or black- 

 ish, sometimes not obvious : feet dull piceous : venter dull pi- 

 ceous. 



Length less than three-tenths of an inch. 



% Head, thorax and metathorax, greenish-blue : mandibles 

 and labrum, dull honey-yellow: thighs obviously tinged with 

 bluish-green: venter on the middle segments green. 

 1837.] 



