Horn.] J-* [Feb. 21, 



sides behind nearly parallel, at apex arcuately narrowed, median line 

 moderately impressed, surface opaque, sparsely punctulate. Elytra 

 elongate, sub-parallel, moderately punctured, sparsely and finely cinereo- 

 pubescent with pruinose aspect. Body beneath and legs blackf some- 

 what more densely pubescent than the upper surface. Length .44-. 60 

 inch ; 11-15 mm. 



Male. First joint of antenna? nearly as long as the head, flattened and 

 nearly sigmoid in form, second joint as long as the two following together, 

 third shorter than the fourth, joints 4-11 very gradually longer and 

 slender. Anterior tibiae with one spur. First front tarsal joint not longer 

 than the second. Lower margin of femora glabrous. 



Female. First joint of antenna? half the length of head, second slightly 

 longer than third, joints 3-11 sub-equal. Middle and hind femora pubes- 

 cent beneath, anterior tibiae bicalcarate. 



Resembles tenuis and unicolor, but the table shows the more remarkable 

 points of difference. 



Occurs in Texas. 



M. unicolor, Kby. Fauna, Bor. Am. p. 241 ; cinerea, Fab. Ent. Syst. 

 Suppl. p. 119; Harris, Bost. Journ. 1, p. 497; Fabricii, Lee. Proc. Acad. 

 1853, p. 343; murina, Lee, debilis, Lee. loc. cit. p. 344. 



The name Fabricii is dropped for the following reasons, viz. ; if Macro- 

 basis be a valid genus the name cinerea is not preoccupied, and should 

 Haerobasis be merged in Epicauta then unicolor Kby. has priority. 



Very similar in form to the preceding, but has usually a more cinereous 

 aspect from the denser pubescence. The sexual characters furnish the 

 greater points of difference. Length .32-. 64 inch ; 8-16 mm. 



Male. First joint of antenna? shorter than the head, slightly broader 

 toward the tip, slightly flattened and very feebly arcuate, second longer 

 than the two following joints together, joints 3-11 gradually but very 

 slightly longer. Anterior tibia? bicalcarate. Lower edge of femora 

 pubescent beneath. 



Female as in the preceding species. 



The species known as murina and debilis appear to be merely badly 

 developed forms and not entitled to rank as species. M. unicolor differs 

 from torsa and tenuis in the male, having two spurs to the anterior 

 tibia?. 



A very widely distributed species, occurring from Canada to Kansas 

 and to Georgia and Arizona. 



M. tenuis, Lee. Proc. Acad. 1853, p. 343. 



More elongate than unicolor and clothed with whiter and more lustrous 

 pubescence. Epistoma, labrum and palpi testaceous at least in the male. 

 Length .62 inch ; 16 mm. 



Male. First joint of antenna? nearly as long as the head, formed as in 

 unicolor, second joint nearly as long as the three following together, 



