ART. 21 ACALYPTRATE FLIES MAUL-OCH 25 



meral angles yellowish; pleura shining black, yellowish in middle 

 and below posteriorly, with a median grey pruinscent vitta. Abdo- 

 men shining black, with a pale yellowish spot on each lateral in- 

 curved portion of each tergite, which may extend on to disk of ter- 

 gite. Legs pale yellow, coxae and femora largely or entirely black, 

 all tibiae with two small anniili, all tarsi with the apical three seg- 

 ments black. Wings black, with many hyaline dots and spots (fig. 

 4). Halteres whitish. 



Postverticals strong; ©cellars long and parallel, in line with an- 

 terior ocellus and wider at base than width across posterior ocelli ; 

 the single orbital bristle long; one or two of the long lateral facial 

 hairs situated on anterior edge of the flat area. Thorax with two 

 j^airs of postsutural dorsocentrals and one pair of prescutellar acro- 

 stichals; scutellum bare or disk, with four marginal bristles. Legs 

 stout, preapical tibial bristle not distinguishable. Wing venation as 

 in figure 4. 



Length, 3-4 mm. 



Tyye. — Female, allotype and paratypes, Mexico City, Mexico, 

 January 1924. Cat. No. 28458, U.S.N.M. 



The flattened part of face in this species is more broadly rounded 

 below than in fascipeimis^ being almost transverse while in the lat- 

 ter it is rather obtusely pointed, presenting a subtriangular appear- 

 ance. The wing markings and venation as well as the coloration of 

 the head, thorax, and legs are very different in the two species, which 

 are all that are now known as belonging to the genus. 



NEOSCUTOPS, new genus 



Generic characters. — Head (fig. 7) similar to that of Scutops, but 

 the face is evenly convex, haired on entire surface, two of the hairs 

 near middle of disk longer than the others, and there is a slight 

 but evident central protuberance on middle of lower margin; frons 

 about half of the head width, depressed in front, with one pair of 

 orbital bristles, the anterior ocellus hardly more than its own length 

 from vertex, laterals on vertex; ocellar bristles long, slightly con- 

 vergent; postverticals divergent; arista plumose; vibrissae absent. 

 Thorax in type covered with threadlike growth of mold or fungus, 

 so that it is not possible to definitely decide the armature, but there 

 appears to be but one pair of dorsocentrals and one pair of long 

 scutellars present and no mesopleurals nor sternopleurals. Wing as 

 in figure 8. 



Genotype. — Neoscutops rofmidipennls, new species. 



NEOSCUTOPS ROTUNDIPENNIS, new species 



Female. — Head testaceous yellow, shining, frons, upper part of 

 face, and occiput, black. Thorax except humeri shining black, the 



