4 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 08 



tibiae and basal two segments of fore tarsi black. Wings fuscous, 

 with a broad costal streak on basal two thirds, and a spot in first and 

 second posterior cells, hyaline. 



A slender species. Ocellar bristles microscopic ; postverticals min- 

 ute; anterior incurved orbital bristles small ; interf rontalia shagreened 

 and more of less transversely striate ; face rounded out in centre and 

 with numerous quite prominent transverse striae; basal segment of 

 antennae as long as second ; haired below, third segment about seven 

 times as long as wide, entire antennae distinctly longer than height 

 of head; arista plumose. Prescutellar acrostichal bristles absent. 

 Fore tarsi elongate and thickened. Inner cross vein distinctly beyond 

 middle of discal cell; extreme apex of fourth vein bent down 

 slightly. 



Length, 4-5 mm. ' 



Type. — Male, allotype, and five paratypes, Higuito, San Mateo, 

 Costa Kica (P. Schild). Cat. No. 28438, U.S.N.M. 



This species is readily distinguished by its striate face and marked 

 wings, though one species of Laiixaniella, nuhecula. described in this 

 paper has the wings marked in similar manner. 



LAUXANIELLA NUBECULA, new species 



Male. — Black, shining. Head black, frontal orbits, face, and 

 checks, glossy, parafacials and sides of occiput silvery pruines- 

 cent; arista and basal two segments of antennae yellow, third 

 segment black. Thorax black, slightly shining, greasy in type, 

 but apparently with whitish pruinescence, a dark central, and 

 interrupted lateral, dorsal vittae; apex of scutellum velvety black; 

 pleura whitish pruinescent. Legs pale yellow, with white dusting 

 on tibiae and tarsi, coxae and femora blackish, apices of latter 

 yellow. Wings dark brown, hyaline at base, rather broadly along 

 costa to beyond middle, and in outer part of second posterior 

 cell. Halteres yellow. 



Frons a little over one-third of the head Avidth at vertex, wider 

 anteriorly, each orbit wider than interfrontalia above, equal to it 

 below; ocellars weak; orbitals strong; total length of antenna 

 greater than height of head, basal two segments subequal in length, 

 third about ten times as long as wide, and longer than arista, the 

 latter plumose; face smooth, prominently and evenly convex, with 

 a linear diagonal depression on each side below eye level. Thorax 

 and abdomen slender. Preapical tibial bristle distinct. Inner cross 

 vein beyond middle of discal cell. 



Length, G mm. 



Type. — Cano Saddle, Gatun Lake, Panama Canal Zone, August 

 6, 1923 (P.. C. Shannon). Cat. No. 28474, U.S.N.M. 



