Horn.] J "A [Feb. 21, 



as well developed as in the other Macrobases, and in no other respect 

 differing from the other individuals. The abdominal segments beneath 

 are rarely entirely black. M. valida Lee. does not appear to differ in any 

 other respect than in being larger than the forms found in Kansas and 

 recognized as the typical forms of the species. 



Occurs from Kansas to Texas and Arizona. 



Of the following species we possess females only and their proper 

 places cannot therefore be assigned them in accordance with the characters 

 made use of in the table at the beginning of the genus. They are as 

 follows : 



M, sublineata, Lee. Proc. Acad. 1853, p. 447. 



Form similar to albida. Head black, densely punctulate and densely 

 cinereo-pubescent. Thorax slightly longer than wide and widest slightly 

 in front of middle, sides in front obliquely narrowed, disc feebly convex, 

 dorsal channel obliterated in front, shallow at base, surface punctulate 

 and pubescent. Elytra black, finely punctato-scabrous, apex cinereo- 

 pubescent, remainder of surface with cinereous and black pubescence in- 

 termixed, and with three very fine lines of totally black hairs. Body 

 beneath black, densely cinereo-pubescent. Length 1.05 inch ; 20 mm. 



Male unknown. 



!■'■ male. Antennae of same form as in longicollis. From the structure 

 of the antennas of the unique before me, it is probable that were the 

 male known its position would be near longicollis. 



One female from Texas. 



M, tenella, Lee. Journ. Acad. IV, 1858, p. 23. Head pale yellowish 

 testaceous, moderately shining, very sparsely punctured and sparsely 

 cinereo-pubescent. Thorax colored as the head, longer than wide, nar- 

 rower than the head, surface rather densely punctured and sparsely pub- 

 escent. Elytra black, punctured, sparsely pubescent with cinereous hairs. 

 Body beneath piceous, mesosternum and tip of abdomen pale rufo-testa- 

 ceous. Logs pale rufo-testaceous. Length .48 inch ; 12 mm. 



Antennas pale testaceous, first joint one-third the length of head, 

 scarcely broader to apex and feebly flattened, second joint longer than 

 half the first, third slightly longer than the second, fourth equal to 

 second, joints 4-11 sub-equal and slender. 



I cannot determine with certainty the sex of the specimens before me, 

 as they are so injured at the tip of the abdomen as to be unfit for deter- 

 mination. The characters given serve to distinguish it from all the other 

 species in the genus. In the list it appears as an Epicauta. 



Collected by Captain Pope, on the Staked Plain of Texas. 



M. linearis, Lee. Journ. Acad. IV, 1858, p. 23. 



Form slender, elongate. Head piceo-testaceous, moderately shining, 

 punctulate and sparsely cinereo-pubescent. Thorax narrower than the 

 head, one-fourth longer than wide, sides behind parallel, anteriorly 

 obliquely narrowed to the apex, color piceous, surface moderately shining, 

 punctured, sparsely cinereo-pubescent and with fine smooth median line. 

 Elytra luteous, finely punctate-scabrous and sparsely cinereo-pubescent. 



