3oo MEMOIRS ON THE COLEOPTERA 



nearly flat and obtusely cuneiform and, as an extreme of this type, 

 canescens has the most remarkable clypeus of the genus, it being 

 flat, elongate, and triangular, with the apex narrowly truncate; 

 these various forms are united by gradual intergrades, so that they 

 cannot in any instance serve for more than group distinction. 

 The anterior tibiae are usually tridentate in both sexes, with the 

 upper tooth feebler in the male, but sometimes both the external 

 teeth become virtually obsolete in that sex, as in the isolated 

 geminata of Chevrolat. The pronotal base, at the scutellum, is 

 almost invariably sinuate, but in some forms, such as kerni and 

 (Bstuosa, the base along the scutellum is broadly arcuate or sub- 

 truncate, without even a decided trace of a sinus in any known 

 individual. Euphoria is an exceedingly difficult genus in which to 

 fix definitely the value of recognizable differences among the very 

 numerous taxonomic forms, and for this reason some of those 

 named below are given the provisional status of subspecies. All 

 the Mexican and Central American forms in my collection are 

 included; they are assignable to the following eight subgeneric 

 groups : 



Antennal club much longer in the male than in the female; clypeus large, 

 subquadrate, generally distinctly elevated at the sides as well as at 

 apex 2 



Antennal club usually less developed and never much longer in the male, 

 being equal in the sexes or very nearly; pronotum strongly sinuate at 

 the scutellum; anterior tibiae tridentate in both sexes 7 



2 Base of the pronotum abruptly and distinctly sinuate at the middle; 

 anterior tibiae distinctly tridentate in both sexes 3 



Base evenly arcuate to sinuato-truncate at the middle, the feble sinus, 

 if present, not sharply limited at the sides 4 



3 Pronotum glabrous or with inconspicuous hairs, which, if more 

 abundant, as in rufina, are regularly distributed. Group I (fulgida) 



Pronotum densely and very irregularly pubescent. ... Group II (inda) 



4 Anterior tibiae tridentate in both sexes 5 



Anterior tibiae bidentate (cf) or tridentate (9), sometimes without 

 external teeth in the male 6 



5 The tibial teeth well separated; body without tomentose spots at 

 any part Group III (kerni) 



The teeth approximate and more apical ; body with conspicuous tomentose 

 spots Group IV (subtomentosa) 



6 Body with or without tomentose spots, but never having them on the 

 elytra, the pronotum and elytra more or less evidently vittate, the 

 vittae either solid as in geminata, or composed of comminuted 

 small spots as in arizonica Group V (geminata) 



