94 R. W. Dawson 



Tubercles much smaller, and more nearly covered with tomen- 

 tum; first joint of antennae with rufous hairs; antennal club 

 rufous or cinereous asper 



6. Elytral intervals with continuous, single rows of short, erect, 

 scale-like hairs; prosternum usually produced into a spine be- 

 hind the anterior coxae atrox 



Elytral intervals without continuous, single rows of short, erect 

 scales 7 



7. Larger species, length 8-12 mm 8 



Smaller species, length 5-7 mm 10 



8. Lateral margins of elytra serrated or roughened, especially to- 

 ward the base 9 



Lateral margins of elytra even or continuous, not serrated; 

 scales of elytral striae arranged in double rows, more or less 

 continuous basally especially on the first stria, elsewhere more 

 or less interrupted unistriatus 



9. Median, longitudinal sulcus of pronotum usually entire, at most 

 feebly interrupted by a transverse ridge, sides of the sulcus 

 nearly straight; elytral tubercles with semi-erect, brownish 

 scales tuberculatus 



Median, longitudinal sulcus of pronotum more or less inter- 

 rupted medially by the narrowing of the sides and a feebly ele- 

 vated, transverse ridge; elytral tubercles with semi-recumbent, 

 yellowish scales sonorae 



10. Discal area of pronotum not, or only slightly sulcata or im- 

 pressed 11 



Discal area of pronotum with four large, shallow impressions 

 insularis 



11. Elytral intervals more or less convex, with the scales arranged 



in short, longitudinal, double rows 12 



Elytra black, shining, the intervals nearly flat, with very feeble 

 transverse elevations, each bearing a transverse row of two or 

 three short, erect, brownish hairs or scales laticollis 



12. Anterior tibiae above the lateral tooth serrulate; alternate in- 

 tervals of elytra more prominent, and with the pubescent spots 

 more elongated scaber 



200 



