44 GEO. H. HORN, M. D. 



MECAS Lee. 

 Our species are few in number and may be known by the following 

 characters : 



Body above concolorous. 



Legs black. Thorax usually with two feeble callosities. Body above uni- 

 formly clothed with cinereous pubescence iiioriisttit. 



Legs black. Thorax without callosities. Body above sparsely clothed 

 with cinereous pubescence, thorax at sides and middle, elytra at 

 suture and sides more densely clothed with yellowish white pubes- 

 cence iiiai'ginella. 



Legs or at least the femora red. 



Thorax with four or five callosities. Surface sparsely cinereo-pubescent, 



suture and margin more densely pergrata. 



Thorax without callosities. Surface very sparsely pubescent. Femora red, 



tibise usually dark renioralis. 



Body above bicolored. Head and thorax reddish yellow. 



Elytra very sparsely cinereo-pubescent, suture more distinctly. ..rulicollis. 



M. inoruata (S&y) ; saturnina Lee. 



The form of the thorax varies considerably in this species, and may 

 be almost truly cylindrical or arcuate at the sides; the width often 

 equals the length, many times exceeding it. The callosities of the 

 thorax which are feeble at best may be wanting. 



Occurs from Dakota to Texas. 



M. marginella Lee. 



This species shows no variation except in size in the dozen or more 

 specimens I have seen. 



Occurs in Texas and Illinois. 



M. pergr^ta (Say); gcntilis Lee. 



There are always four sometimes five callosities on the thorax. 

 The upper surface varies in color from piceous to rufous and is 

 sparsely clothed with cinereous hair. A narrow sutural and marginal 

 line is more densely pubescent. The legs are rufous, the tibiae at tips 

 sometimes darker. 



Occurs in the same regions with inornata. 



M. reiuoralis (Hald.) 



This is the smallest species. I have seen but four specimens not 

 varying from the characters in the table. 

 Occurs in Georgia. 



M. ruficollis n. sp. — Piceous, head, thorax and epi pleura pale rufous, 

 elytra black. Antennae black. Head pale rufous, darker behind tlie eyes and 

 at antennal tubercle, surface sparsely punctured and sparsely clothed with 

 very fine pale pubescence. Thorax slightly wider than long, sides slightly 



