390 BULLETIN UNITED STATES GEOLOGICAL SURVEY. 



7. P. f tenuis. 



Aethus tenuis Walker, ib., i, p. 151, No. 22. 



" Black, elliptical, shining, nearly flat, a few long bristles on the sides of 

 the head and of the thorax. Head nearly smoot h , about half the breadth 

 of the thorax. Eyes black. Rostrum reddish. Antennae piceous, about 

 one-third of tbe length of the body; joints from the second to the fifth 

 about equal in width. Thorax nearly smooth, with two slightly curved, 

 transverse furrows, one very near the fore border, the other across the 

 middle; a slight longitudinal furrow extending for a short space hind- 

 ward from the first transverse furrow. Scutellum with a few punctures? 

 much longer than its breadth at the base. Legs piceous, stout. Fore 

 wings almost smooth, with two striae near the costa and two near the 

 hind border; membrane brown." 



Length of the body 2f lines. 



Inhabits Orizaba, Mexico. 



Melan^thus Uhler. 



Long-oval, or elliptical; the margins of head, pronotum, and corium, 

 as well as those of the venter, fringed with remote bristles. Head 

 semicircular, the margins slenderly recurved, ciliated, but destitute of 

 spinous teeth ; tylus as long as the lateral lobes ; base of the head broad. 

 Dot scooped out each side; bucculge almost percurrent, widened at the pos- 

 terior end; rostrum reaching almost or quite to the intermediate coxse ; 

 the basal joint as long as the bucculse ; the second longest, a little longer 

 than the third; third longer than the fourth; the fourth subequal to the 

 basal one. Antennse moderately stout and long; the basal joint stouter 

 than the second, but not so stout as the fifth, a little narrowed at tip 

 second more slender, either longer or shorter than the third ; third thicker 

 toward the tip; fourth longer; fifth longest, and subfusiform like the 

 preceding. Pronotum transverse, very feebly convex, the lateral mar- 

 gins straight or nearly so, with the edge recurved; the anterior margin 

 broadly sinuated, the posterior margin subtruncated. Scutellum longer 

 than broad, acutely narrowing toward the tip; the tip narrow, acutely 

 rounded, overlapping the inner angle of the corium. Exterior area of 

 the corium broad, depressed ; the costal margin curved inward toward 

 the tip, leaving the connexivum exposed posteriorly ; the posterior margin 

 moderately oblique, feebly arcuated; the exterior angle a little produced. 

 Legs normal, the anterior tibise very moderately compressed. Ostiolar 

 canal long and slender, running outward about two-thirds the length of 

 the episteruum, broad and rounded at tip. 



1. M. robustus, new sp. 



Intensely black, shining, tolerably broad, almost flat above. Head 

 disk-like, broad, depressed around the front, very coarsely, conflueutly 

 punctured; the margin almost regularly semicircular, the edge trench- 

 ant, elevated ; the tylus rugulose. Ocelli small, black, placed near the 



