Genus Bironella. 121 



and size. The small sub-marginal cell resembles Megarliinus 

 and Toxorhynchitesy and to some extent Uranotaenia. 



Bironella gracilis. Theobald (1905). 

 Ann. Mus. Nat. Hung. HI., p . 69 (1905) (Pis. II. and III.). 



Thorax brown, with short dull golden hairs ; pleurae and 

 scutellum paler ; palpi and proboscis brown. Abdomen black, 

 narrow, expanding apically, with brown hairs, which become 

 golden-brown on the large genitalia. Legs long, brown, pale 

 yellowish-brown at the base and below the femora. Wings with 

 brown-scaled veins, the membrane tinged with brown along 

 the costa. 



£ . Head brown, with numerous yellowish and black upright 

 fork-scales, the latter very thin with bifid apex, the former 

 broader with expanded apex with numerous serrations, and 

 apparently a few irregular narrow outstanding pale scales of 

 similar size throughout their length. 



Proboscis moderately long and thin, clothed with deep brown 

 almost black scales, labellae very acuminate ; palpi not quite as 

 long as the proboscis, scaled with deep brown scales, swelling 

 gradually towards the apex, the apical segment large, one joint 

 only can be detected, but probably a basal one exists. Antennae 

 brown with pale bands below the whorls of verticillate hairs, 

 hairs deep brown. 



Thorax dark brown with slaty sheen and with short dull 

 golden curved hairs projecting backwards ; scutellum pale 

 yellowish-brown ; metanotum deep brown. 



Abdomen black, nude, but with black hairs, narrow basally, 

 but expanded apically ; genitalia densely hairy. 



Legs long and thin, brown, the coxae and under side of 

 femora pale ochreous. Ungues apparently all equal and simple. 



Wings with brown scales. The sub-costal cell tinged with 

 brown, rest of the membrane transparent ; the first sub-marginal 

 cell very small, its stem more than four times the length of the 

 cell ; the posterior cell about two and a half times the length 

 of the former and about twice its width ; stem of the second 

 posterior cell a little longer than the cell, curved about its 

 centre ; the third long vein also curved, continued to the base 

 of the wing as a distinct pseudo-vein ; fifth vein with its upper 

 branch distinctly waved, after its junction with the posterior 

 cross- vein ; sixth long vein nearly straight until its apex, where 



