78 



UNITED STATES NATIONAL MUSEUM BULLETIN 2 24 



first segment, 3 in the middle of the lateral margin of 

 the second segment, 2 or 3 on the third segment, and 1 

 on the fourth segment. Only six segments are visible. 

 The terminalia are large, especially the epandrium, 

 which is rotate at least 45 degrees. The epandrium lat- 

 erally bears long, thin, centrally convex, uneven, pos- 

 teriorly rounded, transparent, winglike processes, which 

 leave a deep, notched recess between them in which the 

 long, setate proctiger fits. Ventral surface of termi- 

 nalia widely open, much of it tucked in under the sixth 

 tergite ; the lateral gonopod is large, subtriangular, ex- 

 tends out from under the tergite. The aedeagus ex- 

 tends downward and backward and then is strongly bent 

 and reflexed posteriorly as a single tube enclosed by 

 slender, pronglike pseudoclasper on each side, the me- 

 dial surface of which bears a brush of erect, bristly 

 hairs. 



Distribution: Neotropical: Laphygmolestes flavipes, 

 new species. 



Laphygmolestes flavipes, new species 



This species is characterized by the light brownish 

 yellow legs, the minute, appressed, brassy setae of the 

 mesonotum and the appressed, yellowish white bands 

 of hairs on the abdomen. Length 10 mm. 



Male. Head : The head is black, all the pile and bris- 

 tles pale yellow, except on the lower occiput where it is 

 almost white. Antenna black with the third segment 

 brownish black. 



Thorax : The thorax is black, moderately shining on 

 the mesonotum, the setae brassy in color, the pollen 

 rather pale brassy yellow. 



Legs : The legs are wholly brownish yellow, the pile 

 and bristles everywhere of the same color, except for a 

 narrow band of appressed, brown setae anteriorly on 

 the anterior and middle tibiae and the whole dorsal 

 half and whole lateral surface of the hind femur, 

 and the whole of the hind tibia where the setae are dark 

 brown. Dorsal pile of tarsi brassy. Extreme apex of 

 the hind femur and extreme base of its tibia black. 



Abdomen : The abdomen is shining black with a slight 

 opalescent reflection. Middles of the second to fourth 

 tergites gently convex so that from the side the abdo- 

 men appears corrugate. The extensive, appressed setae 

 are black, except for the bands on the posterior margins 

 and the posterior comers, which are yellowish white. 

 Basal half of terminalia black but changing to brown 

 before becoming transparent on the lateral wings of the 

 epandrium. Proctiger pale, brownish yellow. 



Type : Male, Corumba, Brazil, December 14-25, 1919. 

 Type in the Cornell University collection. 



Nyximyia, new genus 



Type of genus : Nyximyia niger, new species. 



Characterized by the numerous, quite stout bristles 

 over the whole of the face; stout, vertical bristles of the 

 occiput; the numerous, stout bristles on the margin of 

 the scutellum; united prosternum; absence of bristles 



or pile on the lateral metanotum and by the character of 

 the wing. The first and fourth posterior cells are each 

 closed with a long stalk, the marginal cell is widely 

 open, although the second vein is more or less recurrent, 

 and the ambient vein is wanting. Male terminalia 

 rather large and inverted. The relatively large in- 

 verted terminalia are much larger than in Laphystia 

 Loew and are rather like that of Nusa Walker. The ab- 

 sence of the ambient vein and the remarkably stout, 

 widely distributed bristles of the face and the stout 

 bristles of the occiput are also characters found in 

 Nusa. The widely open marginal cell and the venation 

 generally are suggestive of Laphystia. It may be re- 

 garded as an annectent genus between the two groups. 

 Length 14 mm., including antenna. 



Head, lateral aspect: The face is moderately long 

 and conspicuous in lateral profile but is gently and 

 slightly convex so that it is almost equally prominent 

 above and below. The subepistoma is long and oblique, 

 the cheeks short, the occiput is prominent below becom- 

 ing less in evidence towards the vertex and the eyes are 

 developed a considerable distance laterally beyond the 

 occiput. Distinct bristles begin a little below the mid- 

 dle of the occiput and become exceptionally stout and 

 spikelike on the upper occiput. Sides of front with 

 stout bristles. Vertex but little excavated, the ocellar 

 tubercle low and with only short, fine, bristly hairs. 

 First antennal segment 2!/2 times as long as the second, 

 which is short and almost beadlike. Lateral and ven- 

 tral margins of the first segment with numerous, stout, 

 black bristles. Third segment missing. Face with 

 some 8 vertical, irregular rows of quite stout, rather 

 long, downwardly curled bristles which are for the most 

 part erect or suberect. Proboscis slender, produced 

 but little beyond the face and directed obliquely for- 

 ward. It is rather tapered on the outer fifth. Palpus 

 composed of two segments ; the first excavated, the sec- 

 ond spindle-shaped, with weak bristles. 



Thorax: The thorax is gently convex and densely 

 covered on the mesonotum with coarse, suberect, bristly 

 hairs. Humerus with abundant, bristly pile and 2 or 

 3 weak bristles. Whole margin of the notopleuron 

 with a row of stout bristles, several of which are espe- 

 cially stout. There are 4 quite stout bristles above the 

 wing. Postalar callosity with 5 long, stout bristles; 

 scutellar margin with 6 or 7 pairs of conspicously stout, 

 long, radiating bristles. Lateral metanotal callosity 

 without bristles or pile. Mesopleuron near the upper 

 posterior corner with 3 or 4 bristles, at least two of 

 which are stout and conspicuous. Postmetacoxal area 

 membranous. 



Legs: All the femora are moderately stout without 

 being swollen ; their pile is rather dense, coarse and bris- 

 tly; this pile is chiefly subappressed but more or less 

 erect ventrally. Bristles are stout, moderately long, 

 but not numerous. Hind femur with a subapical, a 

 dorsomedial, a dorsal, a lateral and a posteroventral 

 bristle. Distributed along this surface are 6 other pos- 

 teroventral bristles. Bristles of the tibiae are short, 

 stout and numerous, in 2 rows on the anterior tibia, and 



