6 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 70 



Usually small (3 — 6 mm.), depressed, margins explauate, usually moderately 

 wide ; antennae slender, at least half the length of the body, front oblique, 

 eyes often large and usually closely set, iuterocular space rarely over half 

 width of head, interocular depression distinct Series B. 



SERIES A 



1. Pronotum dark without trace of yellow or reddish brown, head always 



dark 2. 



Pronotum yellow or reddish brown, sometimes spotted or fasciate, head 

 dark or pale 4. 



2. Head, pronotum, and elytra entirely blue or purple, elytra coarsely 



punctate , (1) violascens. 



Head, pronotum, and elytra black, sometimes with bluish, greenish, or 

 purplish luster, elytra very faintly punctate, nearly smooth 3. 



3. Head with front flat, tubercles indistinct, no trace of reddish brown 



frontal spots, third and fourth antennal joints about equal. Arizona, 



Rocky Mountains, British Columbia, Hudson's Bay (2) lugens. 



Head with front not flat, tubercles distinct, usually with Indistinct reddish- 

 brown spot on either side of front, third antennal joint a little longer 

 than fourth. Georgia, Texas, Illinois (3) concinna. 



4. Head dark, usually with pale front or pale frontal spot 5. 



Head yellowish to reddish brown, sometimes with large dark spot covering 



vertex and front, leaving only margins about eyes pale 10. 



5. Pronotum with a fascia or spots, these sometimes confluent 6. 



Pronotum immaculate, pale yellow 9. 



6. Head nearly black, sometimes with indistinct reddish brown frontal spot ; 



pronotum dull yellow with five piceous spots, these frequently united in 

 an irregular triangular blotch or fascia ; elytra entirely yellow brown or 



with a broad, piceous, median vitta on each elytron (10) fimbriata. 



Head iiiceous, usually with reddish or yellowish frontal spot 7. 



7. Pronotum pale yellow with five black spots, sometimes united to form 



fascia ; elytra yellow with common black sutural vitta and on each 

 elytron a median vitta and narrow submarginal vitta, the last reaching 

 from middle nearly to apex ; body beneath black, margin and last ventral 



segment yellow (8) aemula. 



Pronotum reddish or dull yellow, with five piceous spots sometimes con- 

 fluent, or with a wide band 8. 



8. Elytra varying from deep brown to piceous or black with bluish or greenish 



luster, feebly shining, finely punctate, pronotum over twice as wide as 



long, finely punctate; abdomen with j'ellow margin (4) vians. 



Elytra opaque bluish black, almost smooth, pronotum twice as wide as long, 

 coarsely punctate ; abdomen entirely yellow or with only faint trace of 

 yellow brown in middle (5) discicollis. 



9. Elytra green or black with yellowish white vittae (occasionally elytra 



entirely green), margin usually pale, and yellowish white vitta on each 

 elytron often broken near apex, producing an ! mark on each el.vtron. 



(6) interjectionis. 

 Elytra brown with five large pale yellow blotches on either elytron. 



~" (7) jacobiana. 



10. Elytra not vittate 11- 



Elytra vittate 15. 



11. Rounded oblong-oval, brilliantly lustrous 12. 



Oblong-oval, feebly shining 14. 



