372 MEMOIRS ON THE COLEOPTERA 



Reitter and Weise, but is here left in the position assigned it by 

 Lacordaire merely for convenience. In all of these genera the 

 species are peculiarly prone to develop local varieties or subspecific 

 forms, which adds greatly to the difficulty of taxonomic study. 



Osmoderma Serville. 



The species of this genus are rather numerous in North America 

 but thus far only one has been discovered in the palaearctic regions ; 

 in the neotropics the genus is replaced by the still larger species of 

 Inca. The body is rather depressed in form, the sculpture in most 

 cases very coarse and rough and the movements rather slow and 

 heavy; they are however strong fliers. As in all the other genera of 

 this tribe, the delimitation of species and subspecies among the 

 numerous individuals in most collections, is not altogether satisfying, 

 but insofar as can be determined at present, the forms worthy of 

 names before me are as follows, all the characters being recorded 

 from the male, except when the contrary is stated :* 



Dorsal surface roughly and coarsely sculptured; pronotum having two 



median and two lateral short ridges 2 



Dorsal surface smooth or with the sculpture comparatively fine and 

 sparse throughout; pronotum modified in an entirely different way 



as described below 5 



2 Cavity of the head gradually sloping upward toward base 3 



Cavity abruptly limited behind by a steep wall 4 



3 Body small in size and rather slender, the apical thoracic angles very 

 acute, the sides near them distinctly sinuate. Body elongate, de- 

 pressed, piceous-black, the elytra obscure rufous, the pronotum 

 with distinct green metallic lustre, the elytra with similar though 

 feebler lustre; head nearly flat between the high supra-antennal pro- 

 minences, not sloping upward at all behind, having very shallow 

 sculpture of interlacing wavy arcuate lines and extremely minute 

 punctulation; base with coarse discrete punctures; clypeus two-fifths 

 wider than long, with very feeble sparse interlacing lines and annuli, 

 the reflexed apex not medially sinuate; prothorax a third wider than 

 long, the four short subanterior ridges very well developed; sides 

 obtusely prominent at the middle, converging and very feebly 

 sinuate thence to the base and more converging and sinuate to the 

 apex; punctures rather coarse and deep, close-set anteriorly and 

 laterally, elsewhere very sparse; scutellum with a few fine punctures; 



* I am glad to note that in my contention for the use of the feminine gender in 

 words of this kind, I am upheld by the decision of Burmeister. That author arrived 

 at his determination to consider the word Osmoderma feminine, and not neuter, 

 through philological reasoning, while my action was based rather upon the desirability 

 of preserving nomenclatorial consistency. 



