1928] New Genus and Species of South American Masarids 195 
and vertically truncate behind, not swollen on the sides; dorsal 
areas broadly separated from each other by the postscutellum; 
concavity wide and shallowly depressed, with a fine, longitudinal 
median carina which runs from the postscutellum to the much 
thickened lower (apical) margin; superior, lateral and inferior 
ridges broadly rounded; lateral angles not produced, rounded; 
ventral areas fused with the metapleura. Lateral scales of the 
articulation of the abdomen narrow, broadly rounded. Ab- 
domen moderately elongate, of almost normal shape, the several 
segments not conspicuously constricted basally. First tergite 
transverse, as wide as the second, broadly rounded in profile and 
not angular between the anterior, sloping part and the posterior, 
horizontal area; the horizontal portion about three times as 
wide as long. Second and third tergites with a slightly depressed, 
transverse line (or constriction) in or before the middle, more 
pronounced on the second tergite; last tergite normally convex; 
all the sternites normal, the apical one convex throughout, with 
a deep, narrow notch at apex; apex of first to fifth tergites with 
a narrow, translucent margin, which, however, is not raised nor 
set off by puncturation. Legs moderately stout, of normal 
shape; middle femora and tibiae not appreciably swollen nor 
flattened; all coxae and trochanters unarmed and of normal 
shape; front tarsi of normal shape, slender; anterior tibial spur 
strongly curved, slender, acute; middle tibia with two spurs of 
unequal length; larger posterior spur trifid at apex; tarsal claws 
simple. Wings with the venation of Trimeria : two closed sub- 
marginal cells; the medio-cubital cross- vein ( m-cu ) attached 
basad of the submedian vein (M4-\~Cu ) ; radial cell very broad, 
not appendiculate; fore wing not plaited; posterior lobe of hind 
wing well developed. 
Body entirely covered with dense, microscopic puncturation 
(not visible with a hand lens); in addition with scattered fine 
punctures, which become larger, deeper and denser on the thorax 
and still coarser over the raised portion of the scutellum; the 
depressed apical margin of the scutellum with fine longitudinal 
striae. The puncturation is still distinct on the first tergite, but 
becomes very' faint and sparse on the succeeding tergites and on 
the sternites. Apical half of the clypeus granular. Head and 
