258 PROCEEDINGS OF THE NATIONAL MUSEUM vol. no 



66. Apex of prothorax distinctly constricted; beak slightly punctured beyond 



middle (Mexico, Distrito Federal) mexicanum Wagner (p. 383) 



Apex of prothorax slightly constricted; beak strongly punctured in rows, tip 

 smoother (Illinois, Kansas, Colorado) coToradense Fall (p. 378) 



67. Mucrones simple 68 



Mucrones dentate or angulate ventrally 70 



68. Size 1.5 mm.; dorsal surface of prothorax deeply, closely, coarsely punctured 



(Iowa, Missouri, Kansas) minor Smith (p. 355) 



Size generally larger than 1.8 mm.; dorsal surface of prothorax more sliallowly 

 punctured 69 



69. Antennae inserted at basal two-fifths of beak; beak in dorsal view nearly 



parallel-sided; prothorax little wider at base than apex (holarctic; North 

 Carolina to New England, west to Washington, south to Utah). 



simile Kirby (p. 278) 



Antennae inserted at basal third of beak; in dorsal view beak attenuate 



toward apex; apex of prothorax seven-tenths as wide as base (Guerrero; 



Guatemala) hadromenmi Wagner (p. 328) 



70. Beak shorter and stout, at most slightly longer than prothorax, in lateral 



view attenuating to apex, more or less sulcate laterally; frons not wider 



than dorsal tip of beak 17 



Beak more slender and subparallel apically, distinctly longer than prothorax, 

 not sulcate laterally; frons generally wider than dorsal tip of beak . . 73 



71. Elytra reddish bronze, legs in part rufous (Veracruz; Guatemala). 



vinosum Sharp (p. 294) 

 Elytra black, aeneous; legs black 72 



72. Beak shorter than prothorax; frons slightly narrower than dorsal tip of beak 



(Veracruz, Mexico, Morelos, Michoacdn, Guerrero). 



glyphicum Sharp (p. 292) 



Beak slightly longer than prothorax; frons equal to dorsal tip of beak (Baja 



California) chuparosae Fall (p. 291) 



73. Prothorax black, elytra blue; prothorax with noticeable prominence on lateral 



basal region (Argentina; Brazil) . . . lativentre B6guin-Billecocq (p. 374) 



Prothorax and elytra of same color, black; lateral basal region of prothorax 



not prominent 74 



74. Antennae inserted at distance from eye one-third greater than width of frons; 



beak in side view nearly parallel-sided in apical third^(Washington, Wyo- 

 ming, Colorado, Utah, California, Durango, Mexico). 



proclive LeConte (p. 289) 



Antennae inserted at distance from eye more than one-half greater than 



width of frons; beak in side view attenuate to apex 75 



75. Antennae inserted in front of basal third of beak; elytral pubescence uniform; 



prothorax at middle not narrower than base (New Mexico, Arizona). 



dolosiim Fall (p. 370) 



Antennae inserted behind basal third of beak; pubescence forming a more or 



less distinct spot at base of interval 3; prothorax widest at base ... 76 



76. Size larger than 2.50 mm.; mucrones dentate apically (Puebla, Mexico, Dis- 



trito Federal, Guerrero) submctallicum Boheman (p. 330) 



Size about 1.75 mm.; mucrones angulate apically (Tabasco). 



adaetum, new species (p. 284) 



