AitT. 1 NEW DIPTEEA FROM SOUTH AMERICA ALDRICH 21 



ginal row, no discals on any of the segments. Legs black ; mid tibia 

 with two erect bristles near middle of outer front side, two on outer 

 hind, and one more sloping on flexor ; hind tibia with several irregu- 

 lar on outer hind, two on inner hind and two on outer front side. 



Wings subhyaline ; third vein with 2-3 setules at base, fourth vein 

 with rounded oblique bend, thence nearly straight to costa, more 

 erect than usual. 



Female. — Front 0.43 of head width at vertex, face 0.58 just above 

 vibrissae. Second antennal joint one-half the third; a pair of 

 proclinate orbitals. 



Length, male 7 mm. ; female 6.3 mm. 



Described from a joair collected at Perales, Chile, by Eev. A. 

 Pirion. 



r^/pe.— Male, Cat. No. 41390, U.S.N.M. 



Genus SELENOMYIA Biauer and Bergenstamm 



Selenomyia Brauer and Bergenstamm, Zweifl. Kais. Mus., pt. 5, 1891, p. 

 361 ; pt. 6, 1893, p. 170.— Aldrich, Annals Ent. Soc. Amer., vol. 18, 1925, 

 p. 459. 



The type species, and the only one so far known, is S. hi'evicomis 

 Brauer and Bergenstamm, mentioned and more or less described in 

 all the above references. Only one specimen is known, the type, 

 which I borrowed from the Vienna Museum and later sent back. I 

 am now describing three additional species which I refer to this 

 genus ; like the genotype, they are from Chile, where it seems to be 

 a characteristic form. The third species, facialis, differs from the 

 others in having the parafacials, hairy and may ultimately go into 

 a new genus; but from the slight taxonomic value of this character 

 in other dexiid groups, as, for instance, Ptilodexia and Rutilia, I 

 do not believe it is generic in the present case. 



In this genus there is a high, sharp carina on the face, and the 

 facial ridges are decidedly convergent and prominent below, so that 

 there are well-marked and deep subantennal depressions which are 

 entirely separated. The cheek is almost equal to the eye height and 

 the parafacials are broad, about two-thirds of the cheek. 



KEY TO THE SPECIES OF SELENOMYIA 



1. Abdomen shining green, without pollen vlrens, new species. 



Abdomen black, with pollinose markings 2 



2. Tibiae reddish-yellow ; second and third abdominal segments with a pair of 



arcuate spots of pollen brevicornis Brauer and Bergenstamm. 



Tibiae black, abdominal spots not arcuate 3 



3. Parafacials bare except on upper part plena, new species. 



Parafacials with coarse hair down to the lower edge of the eye. 



facialis, new species. 



