NORTH AMERICAN COLEOPTERA. 277 



satisfactory, and the present one may prove no better than its prede- 

 cessors, but the structure of the antennae and the presence of certain 

 apterous forms enables several divisions to be made, so that the diffi- 

 culties are somewhat reduced. 



Of but few species are the food plants known, these have been 

 recorded in the specific names of the species themselves. 



With these preliminary remarks the following table is presented : 



AntciiiiiE with joints 2-3-4 successively longer; body always winged 2. 



AnteuTise witli joints 2-3-4 of equal length, or at least with the fourth not lon- 

 ger than the second ; body winged, or apterous ...12. 



2. — Species rufotestaceous, brown or piceous; form always convex, except in 



postremns 3. 



Species yellowish white, or pale yellowish testaceous; form usually de- 



pre.ssed 8. 



3. — Eufotestaceous, or pale castaneous species 4. 



Brownish, or piceous species , 5. 



4. — Thorax nearly square ; color bright rufotestaceous, each elytron with a 

 small, darker cloud ; surface very shining, punctuation very indis- 

 tinct 1. Heliophyli. 



Thorax very plainly broader than long, dull rufotestaceous; jjunctuatiou 



distinct 2. siibrulus. 



5. — Thorax without basal marginal line; a faint teneous surface lustre 6. 



Thorax with basal marginal line; without aeneous lustre 7. 



6. — Thorax not twice as wide as long ; punctuation of elytra vaguely suhstriate 



form more oblong 3. turbntus. 



Thorax very nearly or fully twice as wide as long; form short, robust; 



elyti'al punctuation very much confused 4. oregoiieusis. 



7. — Form robust and convex, rufopiceous or brown ; species large. 



5. tradticttis. 

 Form oblong, rather depressed ; piceous, umbones paler, species small. 



6. post rem us. 

 8. — Body above not distinctly punctate, either on thorax or elytra; body be- 

 neath coucolorous 7. repaiKliis. 



Body above distinctly punctate 9. 



9. — Body beneath rufotestaceous 10. 



Body beneath piceous or brown 11. 



10. — Form depressed; surface shining, as if varnished ; elytral jiunctuation fine. 



smooth at apex 8. livens. 



Form moderately convex; surface less shining; elytral iiunctuation very 



distinct, even at ape.x 9. Viiuiis. 



11.— Thorax and elytra similar in color 10. OCl'ideiitalis. 



Thorax and head decidedly reddish, elytra yellowish 11. bicolor. 



12. — Body more or less fully winged ; elytra wider at base than the thorax, um- 



boiie distinct 13. 



Body apterous; elytra not wider tiuin the thorax, liumeri oblique, umbone 

 wanting; lateral margin visible from above at humerus 17. 



