Coleopterological Notices, III. 125 



In other words each group is so heterogeneous, and the interos- 

 culating lines of affinity between them so numerous, that it seems 

 impossible to consider them as having full generic value. 



The form and extent of the anterior coxae and of the prosternal 

 process which separates them, constitute the best characters for 

 minor subdivisions, for these appear to be the most constant within 

 the limits of the groups. 



The fourth joint of the maxillary palpi is usually in the form of a 

 right-angled triangle, with the right angle at the point of attach- 

 ment, but sometimes the two sides form an angle which is slightly 

 less than right, the apex becoming shorter; it is generally quite 

 robust, but occasionally becomes decidedly slender. The eyes, tarsi 

 and antennas vary greatly in size and form in the various species, 

 and appear to be but slightly affected by sex. 



The sexual differences are stated to be quite pronounced in many 

 of the European species, but in the North American they are cer- 

 tainly not remarkably so, and, as there is often much difficulty in 

 determining the sex of individuals, but little attention has been 

 given to this subject in the following descriptions. 



The punctuation generally varies to a considerable degree, and 

 sometimes appears to be coarse or rather fine in the same individual 

 according to the direction of the reflected light ; the elytra often 

 have to be held, therefore, in a very oblique position with reference 

 to the light, in order to see that the impressed lines, which are 

 nearly always distinct, are not accompanied by series of punctures 

 in such species as fraterna and nigerrima. 



Our species may readily be separated into three groups as follows: 



Anterior coxae rather small, separated by a comparatively wide prosternal 

 process, the latter longitudinally convex and attaining the level of their 



apices I 



Anterior coxae separated by a thin prosternal lamina. 



The coxae very large, conoidal and prominent, almost contiguous at apex, 

 the prosternal lamina deeply placed between them, and generally more 



or less horizontal II 



The coxae rather small, the lamina longitudinally convex and attaining the 

 level of their apices Ill 



Groups I and II both contain species with and without the red 

 humeral spots, and these groups are peculiar to the eastern parts of 

 the continent. Group III contains no species as far as known with 

 the humeral maculation, and is peculiar to the regions west of the 



