180 GEO. H. HORN, M. T). 



The special characters of the species have been reproduced in the fol- 

 lowing synoptic table, and seem sufficiently plain to be passed without 

 comment. In the specific descriptions there will be no mention of the 

 usual three dorsal punctures of the thorax. The table is presented as an 

 aid for determination, but it must not be supposed that isolated specimens 

 can be at all times determined from a table, or even from the most labored 

 descriptions. 



Species of larger size; thorax as wide as long, not narrowed in front 2. 



Species of smaller size; thorax narrowed in front: elevated line at base of first 



three dorsal segments straight ....6. 



2. — Basal line of dorsal segments in form ' . 3. 



Basal line straight 4. 



'.J. — Head large in both sexes, abdomen above coarsely punctured, last ventral of 



% triangularly notched aenetis. 



Head small, rounded, abdomen above much smoother along the middle, last 



ventral of % with oval notch atratiis. 



4. — Black, or piceous species 5. 



Bicolored species, black, thorax and base of abdomen red laetuliis. 



5. — Elytra very black, opaque, surface alutaceous and not deeply punctate. 



alutacens. 

 Elytra shining, distinctly punctate. 



Elytra closely punctured, surface bright aeneous, thorax with a peculiar gol- 

 den iridescence sericiniiN. 



Elytra rather sparsely punctate, without aeneus lustre. 

 Head large, and transverse in both sexes. 



Elytra distinctly shorter than the thorax, thoracic punctures small and 

 indistinct, those of the abdomen small and not numerous. 



per versus. 

 Elytra not shorter than the thorax, thoracic punctures large and deep, 



those of the abdomen larger and more numerous biicepliallis. 



Head oval, not transverse. 



Species large, more robust, surface very black an<l shining, legs black, 



abdomen very sparsely punctured iiitesceiis. 



Species large, moderately robust, elytra moderately densely jmnctured, 

 usually bronzed, abdomen moderately closely coarsely punctate. 



I'urvus. 

 Species smaller and slender, elytra bronzed, legs piceous. 



iiinbratilis. 



(). — Elytra sub-murieately punctured 7. 



Elytra with simple punctures S. 



7. — Elytra bright blue, legs pale yellow geutilis. 



Elytra slightly bronzed, legs dark. 

 Thorax feebly narrowed in front, dorsum of abdomen moderately closely 



punctate iriiius. 



Thorax very decidedly narrowed in front, dorsum of abdomen very distantly 

 punctured asper. 



