AMERICAN COLEOPTERA. 207 



a. — Protliorax lilack, with sides and basal spots red; elytra with an 



irregvilar elongate apical white spot. 

 0. — Prothorax black with sides red ; elytra as in a. 

 y. — Prothorax black; elytra as in a. 

 Opake black, prothorax with sides, apical margin, median line abbreviated 

 behind, and two basal spots red; elytra very strongly punctured, strire 

 very irregular at sides and behind, interspaces narrow, convex; 3.7 — 



5 mm.; Pa.; Fla 16. triuoisitus Mels. 



a. — Head with two red spots. 

 10. — Opake, black, legs and upper surface spotted with yellow, prothorax 

 strongly densely punctured, with lateral and apical margin, anterior 

 dorsal line and two basal spots yellow; elytra strongly punctured, strise 

 very irregular, visible only behind the middle, outer interspaces convex ; 

 basal and apical margin, humeral blotch surrounding a black spot, a 

 subsutural smooth spot, and a large blotch near the sides pale yellow; 

 pygidium and last ventral segmentspotted with yellow; M-nigrum\\ Hald.; 



3 — 3.7 mm.; Mass.; Ga 17. iiitricatus Suffr. 



Beneath black, sides of ventral segments and pygidium spotted with 

 yellow; legs yellow, hind thighs sometimes with a black or brown spot; 

 above yellow, varied with black; prothorax strongly punctured, with a 

 dorsal stripe wider and narrowly cleft in front, black; there is also a 

 large quadrate spot each side, extending nearer the base than the tip; 

 elytra with tolerably regular strongly punctured strise, black, basal 

 margin, apical blotch, and irregular cruciform spot extencling from the 

 humerus to behind the middle pale yellow; the transverse branch of 

 tiie cross is oblique and extends from the margin nearly to the suture; 

 form narrower and more cylindrical than usual; mollis Hald.; 1.6 — 



3 mm.; Pa.; Fla.; 111.; Ks.* 18. tridens Mels. 



a. — Prothoracic black spots confluent; Pa. 



0. — Middle stripe of prothorax not divided, posterior branch of elytral 



spot wanting; Ks. 

 y. — Colors sufiFused, the black becomes brown, and the yellow becomes 

 ■ dirty ochreous; the spots are ill-defined, and sometimes reduced to 



three brown clouds on the prothorax, and a large irregular sutural 



blotch becoming wider in front; Tex. 

 S. — Prothorax with three brown stripes; elytra with sutural stripe, an 



irregular interrupted dorsal stripe, and three marginal ill-defined spots 



brown; flo n/orwi is Suflfr. ; Fla.; Col. 



11. --More or less mottled in color 12. 



Uniform opake black, robust, prothorax very densely punctured, hind 

 angles obtuse not rounded ; elytra with distinct coarsely punctured strise, 

 except near the scutel: 2.5 — 3.5 mm.; Ga.; I11...19. carbouarius Hald. 

 12. — Sides of prothorax strongly rounded and incurved near the base; pro- 

 sternum deeply longitudinally concave 13. 



Sides of prothorax obliquely broadly rounded or straight not incurved 

 behind, hind angles not rounded, with well-defined points; presternum 

 flat, scarcely concave, not narrower behind 16. 



*This species, through its suS'used varieties, forms an excellent transition to 

 some of those (in 17) with irregularly mottled elytra. It seems, however, to 

 diff'or by the prosternum more concave in fiout. 



