304 ENTOMOLOGICAL NEWS. [July, '07 



Elytra without transverse marginal striae at base 2. 



1. Pygidium distinctly margined ; labrum longitudinally carinate on each 

 side ; lateral margin of thorax generally interrupted at middle, 

 but grooved or foveate except near apical angles in the male. 



cacti Lee. 

 Pygidium not margined 3. 



3. Thorax near side margin, slightly below apical third, deeply trans- 



versely grooved, above and below this a smaller, but deeply 

 impressed fovea, the one about middle, connected with the 

 median groove by the marginal groove ; mandibles more or 

 less suddenly dilated at about basal fourth and with a more or 

 less distinct tooth above the dilatation ; labrum obtusely cari- 

 nate on each side; prosternum strongly carinate in front, 



broadly dilated behind beyeri n. sp. 



Thorax near side margin below apical third not grooved, mandibles 

 not dilated at basal fourth 4 



4. Head on each side above each eye with a fovea-like distinct impres- 



sion ; no supra-orbital striae io. 



Head on each side above the eyes feebly depressed, coarsely punctate 

 and with a more or less distinct supra-orbital stria, which is in 

 some species greatly abbreviated and visible at base only . 5. 



5. Labrum longitudinally carinate on each side ; outer carina of under- 



side of middle and hind tibiae denticulate 8. 



Labrum not carinate, outer carina on underside of middle and hind 

 tibiae not denticulate , 6. 



6. Median carina on underside of front tibiae without, or with one, tooth 



like elevation at apical fourth 7 



Median carina of underside of front tibiae with several tooth like ele- 

 vations at apical half 9 



7. Thorax at apical margin, on each side of the emargination, with a 



short impressed transverse line ; sides of thorax near marginal 

 groove not punctate ; lateral groove of thorax relatively broad; 

 strongly widening towards apex and terminating here in a 

 more or less distinct fovea-like impression in both sexes. 



yucateca Mars. 

 Apical margin of thorax without short, impressed line on each side 

 of emargination ; sides of thorax near lateral margin, moder- 

 ately coarsely punctate from base to apex ; lateral groove of 

 thorax narrow, deeply impressed and of nearly equal width 

 throughout, terminating in a very deep, rounded fovea in the 

 male, ihe fovea absent in the female ; supra-orbital stria short, 

 basal vernicis Casey 



8. Mediun carina on underside of front tibiae feebly dentate near apical 



fourth ; supra-orbital stria short, basal ; head without frontal 

 stria ; elytra with inner stria entire, outer short, basal ; supra- 

 orbital stria short, basal quadridentata Fab. 



