160 [Feb., 1847. 



joint longer than the second ; thorax longer than wide, densely and very 

 finely wrinkled. 3 1. long ; 1| 1. wide. 



Brassy-yellow, tinted with golden: head brassy-brown, opake, confluently 

 rugosely punctulate, with the frontal line long, deeply impressed ; labrum, 

 palpi and antenna, rufo-testaceous ; the first shining, impunctured ; the 

 last moderately long, slender, with the third joint distinctly longer than 

 the second : thorax somewhat inequal, dull cupreous, longer than wide, 

 wider at apex than at base, densely and finely rugose, with scattered im- 

 pressed punctures ; medial line distinct, deeply impressed before and behind 

 the middle; lateral tubercle moderate, oblong, obtuse; anterior angles 

 slightly tuberculate : scutellum plumbeous-sericeous, densely and minutely 

 punctured ; elytra strongly tinted with golden, and with a faint violaceous 

 reflection, punctate-striate, transversely rugose; the ordinary humeral and 

 subsutural depressions faint ; truncate at apex : beneath dull silvery-seri- 

 ceous ; terminal abdominal segments rufous; femora brassy-brown, with 

 their basal third, tibiae and tarsi, dull rufous ; hind femora not toothed* 

 Inhabits Pennsylvania. 



6. D. nana. Brassy-yellow, tinted with green ; antennas rufous, second 

 and third joints subequal ; thorax longer than wide ; medial line profoundly 

 impressed. 2 1. long ; 1. wide. Pennsylvania. 



Head dull brassy-green, densely rugose-punctulate, equal, with the frontal 

 impressed line distinct ; mouth rufo-piceous ; antenna ordinarily long, dark, 

 dull rufous, with their tips blackish; basal joint brassy-brown, with the 

 second joint hardly as long as the third : thorax decidedly longer than 

 wide, obviously narrower at base than at apex ; cupreous, finely rugose, 

 with the disk polished and shining ; medial line entire, wide and profound ; 

 basal margin transversely impressed ; lateral tubercle obtuse, slightly ob- 

 long ; anterior angles very feebly tuberculate ; middle of anterior margin 

 ordinarly elevated : scutellum plumbeous-sericeous; elytra rather convex, 

 brassy-yellow, strongly tinted with green, finely wrinkled, striate-punctate ; 

 two slight, obtuse subsutural depressions ; apex rounded : beneath plum- 

 beous-sericeous or brassy-brown ; feet brassy-brown, glossy, with the bases 

 of the femora and tibiae, dull rufous ; hind pair of femora toothed. This 

 species must be closely allied to pusilla, Say, but it differs from that species, 

 according to Say's description, in having the thorax decidedly less punctured 

 than the head, and its middle profoundly grooved. 



" D. guadricollis. Brassy-green ; thorax with the impressed line and 

 lateral tubercle, obsolete." Say, Journ. Acad. Nat. Sc. v. 282, 1. 



Var. a. Dull violaceous. 



Orsodacna, Latr. 



" 0. vittata. Black, punctured; elytra pale testaceous ; suture and outer 

 margin black; feet rufous." Say, Jour. Acad. iii. 430. 



Var. b. Entirely black. Donacia atra, Melsh. Catal. 



0. tricolor. Head, thorax and feet rufous ; elytra testaceous, with the 

 suture and lateral submargin black. 3 4 1. long. Pennsylvania. 



Head rufous, with the vertex indeterminately black ; rugosely punctured : 

 clypeus sparsely punctured ; labrum impunctured ; antennae blackish, with 

 3 basal joints obsoletely rufous; joints 2-4th subequal; palpi and mandibles 

 rufous, the latter with the tips black; eyes black: thorax slightly longer than 



