OF WASHINGTON. 93 



telluni bearing three marginal pairs; abdomen polished, narrow bases of 

 last three segments whitish pruinose, these segments bearing only mar 

 ginal bristles ; fifth joint of front tarsi not compressed, of nearly an equal 

 width, front pulvilli very short; wings hyaline, third vein bristly almost 

 to small cross-vein, the others bare, first posterior cell short-petiolate. 

 Length 4 mm. 



A male specimen from Chinandega, Nicaragua. 

 Type. No. 7797, U. S. National Museum. 



Hypostena gracilis, n. ,sp. 



Black, the face, cheeks, first two joints of antennae and broad base of the 

 third, first three abdominal segments except a dorsal vitta and the base of 

 the first dorsally and apex of the third, also the coxag, femora and tibiae, 

 yellow, the femora and tibiae tinged with brown; vertex about one-third 

 as wide as either eye, frontals descending slightly below base of second 

 antennal joint, antennae four-fifths as long as the face, the third joint only 

 slightly longer than the second, arista thickened on the basal third, the 

 penultimate joint, slightly longer than broad; vibrissae on a level with 

 front edge of oral margin, two bristles above each, face strongly retreating, 

 concave, the cheeks one-fifth as wide as the eye-height, no orbital bristles ; 

 thorax yellowish-gray pruinose, mesonotum marked with four black vittae, 

 three sternopleural bristles; abdome,n yellowish pruinose, apices of the 

 first three segments polished, second and third segments bearing only 

 marginal bristles, the fourth with a marginal and a submarginal row; 

 front tibiae subequal in length to the first three joints of their tarsi, pul 

 villi greatly elongated; wings hyaline, third vein bearing two bristles 

 near the base. Length 6 mm. 



A male specimen from Chinandega, Nicaragua. 

 Type. No. 7798, U. S. National Museum. 



Family HETERONEURID^.* 

 Chaetoclusia, n. gen. 



Near Heteromeringria but the first vein bristly on the apical three-fifths, 

 etc. Two pairs of vertical bristles, three of orbitals, ocellars minute, no 

 postverticals, no bristles on the frontal vitta. vibrissae stout, antennae 

 short, porrect, third joint sub-orbicular, somewhat longer than the second, 

 arista subapical. densely short-plumose, eyes oblique, nearly twice as 

 high as long, cheeks about one-twelfth as wide as the eye-height, face 

 perpendicular, proboscis short and robust, palpi well developed; thorax 

 bearing two pairs of dorsocentral bristles, two pairs of supra-alar, one 

 humeral, two posthumeral, one mesopleural and one sternopleural, scu- 



* The new name Clusiodes is hereby proposed for Heteroneura Fallen 

 (Agromyzides Sueciae, 1823) which is preoccupied by Heteroneura Fallen 

 (Spec. Ent. Dipt. Exhib., 1810). the Utter a synonym of Ca llomyia Me igen 

 (1804) in the family Platypezid;e. 



