320 MEMOIRS ON THE COLEOPTERA 



prominent to broadly rounded as in Leptoferonia, Euferonia, Gas- 

 trosticta, Ferestria and others. Again the basal thoracic foveae may 

 be double or single in the same group, as in Hypherpes and Euferonia. 

 Then also what might appear to be a most important character in 

 estimating genera, that is the number of discal elytral punctures, 

 though in general a rather constant criterion, occasionally becomes 

 unreliable, as for instance in Euferonia, where though normally two 

 in number, there may happen accidentally to be three on one or 

 both elytra, as was a puzzling fact to LeConte in comparing the 

 type of relicta Newm., having three punctures, with his protensa, 

 having but the normal two. The punctures in Cryobius are still 

 more variable, though never single or altogether wanting. So, to 

 repeat, in differentiating genera in this subfamily and fixing their 

 boundaries, a broad conception of general appearance pervading 

 the species is, as a rule, more useful as a criterion than the modifi- 

 cations of special organs. I have endeavored to apply this prin- 

 ciple in some parts of the following table of our supposably generic 

 groups : 



Anterior tarsi with the dilated joints regular in the male 2 



Anterior tarsi with the joints obliquely dilated in the male 25 



2 Met-episterna notably short, never decidedly longer, and generally 



much shorter, than wide 3 



Met-episterna always decidedly elongate 17 



3 Elytra without dorsal puncture 4 



Elytra each with one to five or six dorsal punctures 8 



4 Body short, stout, oblong and convex; head small, the eyes very prom- 

 inent; maxillary palpi with broad and truncate terminal joint, that 

 of the labial broad and securiform; prothorax with irregular duplex 

 basal foveae, but little narrowed at base, with sharp angles and di- 

 versified side margins; elytral striae very deep, the scutellar short. 



Atlantic Regions. [Type Abax chalybeus Palli.] Myas Dej. 



Body elongate, sometimes much depressed 5 



5 Hind and middle tarsi with the joints pedicellate; head very large, 

 tumid behind the eyes; elytral striae moderate, the scutellar very 

 short and feeble; body rather large, resembling a narrow Hokio- 

 phorus. Pacific coast. [Type H. morionides Chd.] 



Hammatomerus Chd. 



Hind tarsi normal, the joints obtriangular 6 



6 Thoracic sides coarsely margined; body very large, the head large, 

 swollen behind the eyes; prothorax subcordiform, with notably 

 prominent anterior, and well defined posterior, angles; elytral striae 

 fine, punctulate, the scutellar short. Pacific coast fauna. [Type 



Feronia atra Dej.] Holciophorus Lee. 



Thoracic sides more or less finely margined, the anterior angles never 

 more than moderately prominent 7 



