56 KANSAS ACADEMY OF SCIENCE. 
are ferruginous, as in rubidapex, but the alule and anal angles* are yel- 
lowish white throughout, or the alule for the larger part. The abdomen is 
black, with scarce a trace of the bluish color, and there is no yellow pile at the 
base. Baron Osten Sacken identified a specimen from Mexico as dives differing 
chiefly from rubidapezx in the color of the alule. In rubidapex the abdomen is 
black, or is so typically, while in dives Westwood described it as blue. A speci- 
men from Yucatan, mentioned under rubidapex, holds an intermediate position 
between this and the two other species, if species they are. 
Mypas——sp.? A single female specimen from Chapada, Brazil, I cannot. 
locate. It is, I believe, the largest specimen of a dipteron ever recorded, meas- 
uring 50 millimeters in length with a spread of wings of over 100. I cannot iden- 
tify the present species with M. heros Perty, inasmuch as there is no yellow 
pile on the,abdomen and the abdomen is deep black, not blue. The wings are 
deep brown with the posterior part yellowish. The lamella of the antenna is red.- 
Mypas claripennis, n. sp. Female. Black. Lamellaof the antenne moder- 
ately dilated toward the extremity. Front with black, the face with white hair. 
Mesonotum moderately shining, with seven densely white pollinose spots, situa- 
ted one either side of the middle, in front, one on each side above the notopleural 
suture, a minute one in front of each post-alar callus, and a larger one in front of 
- the middle of the scutellum. Pleurz whitish pruinose; a tuft of white hair on 
the hind coxz. Abdomen shining; first segment with loose white hair; second, 
third and fourth segments each with a broad band of light golden hair, closely 
appressed and combed outward, concealing the ground color. Hind femora 
moderately thickened ; hind tibe with a spur. Wings nearly hyaline, slightly 
brownish in the costal and subcostal cells and distally; posterior marginal vein 
present. Length, 20-25 mm. 
One specimen, Chapada, Brazil (H: H. Smith). The banded abdomen and 
sere wings easily distinguish this species. It is nearest related to M. chrysites 
Mypas militaris Gerst. 
Mydas vittatus Macq. (preoc.);? Mydas rufiventris Macquart ;? Mydas 
rujiventris Loew; Mydas ventralis Gerst. 
It is not at all improbable that the above synonymy will be found to be correct 3. 
if so, the species should bear the name rufiventris Macq. The species is very 
variable, as I have stated elsewhere. The hair of the face and front in my 
specimens is yellow. 
Mypas quadrilineatus, n. sp. Male. Black. The narrow frontal orbits and 
the sides of the face, extending to the root of the antennz above, densely yel- 
lowish gray pollinose ; pile of face, front and occiput everywhere white. Lamella 
of antenne considerably expanded, equal to about two-thirds the length of the 
third joint. Mesonotum opaque, with two linear stripes, and the narrow lateral. 
margins light grayish yellow pollinose; humeri whitish dusted. Pleure gray- 
ish pollinose, the pteropleurze and cox with white hair. Abdomen shining 
black, the lateral margins of the anferior segments and their posterior margins: . 
laterally yellow. Legs black throughout, with white hair; pulvilli brown ; hind 
tibiz spurred. Wings brownish, darker in front and along the veins; posterior 
marginal cross-vein present. Length, 25 to 27 mm. 
Three specimens, Mexico (H. H. Smith). The slender markings of the 
mesonotum may be easily obliterated. With these specimens there are three 
others from the same localities, that differ only in the presence of complete yel- 
low abdominal bands, and in having the abdomen along the middle, both above: 
