MELANOSTOMA. 



13 



dark bronze, with three ill-defined stripes ; pile yellow ; pleurce and scutellum more steel-blue. Abdomen 

 shining, subopaque, brownish-black, tbe first segment and the anterior angles of the following ones 

 shining metallic. Legs black ; tips of the femora, the four anterior tibise, the base of the hind tibiae, all 

 the metatarsi, and the second joint of the four posterior tarsi, yellow, the remainder of the tarsi brown or 

 blackish ; hind metatarsi clongate, but not thickened. "Wings nearly hyaline ; stigma elongate, yellow ; 

 narrow brown clonds on the anterior cross-vein and aeross from the origin of the third vein to the vein at 

 the base of the last posterior cell. 



Female. Front subshining, black or steel-blue, with an opaque black cross-band above composed of two coale- 

 scent oval spots. Mesonotum black or bluish-black. Abdomen black or bluish-black, with a large 

 opaque or subopaque triangle on the second segment. 



Length 8-9 millim. 



Hab. Mexico, Xucumanatlan 7000 feet, Omilteme 8000 feet, both in Guerrero 

 (H. H. Smith). 



Fifteen examples. This species is very much like M. scitulum, Willist., in structure, 

 differing chiefly in the more elongate first antennal joint. The markings of the face 

 and wings are quite similar, as are the facial grooves. In immature specimens the 

 second abdominal segment may be largely yellowish at the base. 



8. Melanostoma rugosonasus, sp. n., $ . 



Front, below, moderately shining, submetallic black ; above, with a black opaque cross-band below the ocelli. 

 Antennaa red, the upper part of the third joint blackish ; first two joints of about equal length, the third 

 joint as long as the first two together, about twice as long as broad. Face shining black, partly concealed 

 beneath whitish pollen, which, on the sides, is faintly striate ; in the middle, with five, well-marked, 

 slender transverse grooves. Mesonotum moderately shining, brownish-steel-blue, with three darker, not 

 conspicuous, stripes ; scutellum steel-blue. Abdomen shining metallic bluish ; second, third, and fonrth 

 segments each with a posterior black band, extending more or less forward in the middle. Legs : first 

 two pairs reddish- or brownish-yellow, with the base of the femora and the tarsi blackish ; hind femora 

 black ; hind tibia3 and tarsi brown, except the base of the former, which is reddish-yellow ; hind metatarsi 

 elongate. Wings tinged with yellowish ; stigma yellow. 



Length 9 miUim. 



Hab. Mexico, Omilteme in Guerrero 8000 feet (H H. Smith). 



A second specimen, from Xucumanatlan, differs in having fewer transverse wrinkles 

 on the face ; the face in profile very gently concave below the antennae (instead of 

 straight) ; the abdomen more uniformly black, and not distinctly banded ; the legs 

 black and brown, with the knees and the base of the tibise yellow ; and the wings with 

 a large brownish spot ; I am inclined to think that it belongs to a distinct species. 



9. Melanostoma melanocerum, sp. n., $ . 



Front opaque black above, black-pilose. Antennae black, the third joint slightly reddish below ; third joint 

 oval, about as long as the first two joints together. Lace shining black, on the sides with a broad stripe 

 of pollen running from the orbit to the oral margin ; in the middle with four parallel grooves. Mesonotum 

 black, with a slight bronze reflection, but little shining. Abdomen opaque black, the anterior angles of 

 the tbird and fourth segments somewhat reddish. Legs black, the distal end of the four anterior femora, 



