UEANOT^NIA SOCIALIS 907 



segments coarse and pale, ventral surface with scattered coarse cilia which 

 become abundant on distal segments. 



Wings rather broad, hyaline; second vein very closely approximated to first, 

 second marginal cell short, about one-fourth the length of its petiole; second 

 posterior cell larger but much less than its petiole in length; basal cross-vein 

 long, slightly less than its own length from the short anterior cross-vein ; scales 

 of veins dusky brown, small ; distally large, sparse, outstanding, broadly lanceo- 

 late pale scales along forks of second and fourth veins and along entire length of 

 third vein; on basal part of wing an interrupted broad stripe of broad light 

 silvery-blue scales, for a short distance this extends along the fourth vein, then 

 continues more broadly on the fifth vein, extending to about one-third its length 

 from base; fringe very broad. Halteres pale, with large knobs bearing some 

 minute dark scales. 



Legs rather long and slender; vestiture duslcy brown, in some lights black 

 with bluish iridescence; femora pale at base beneath; knees broadly silver- 

 white scaled ; apices of tibiae with a large brilliant patch of white scales. Claw 

 formula, 0.0-0.0-0.0. 



Length : Body about 2.5 mm. ; wing 2.8 mm. 



Male. Proboscis long and slender, dilated at apex; labellae large; apical 

 portion with many rather coarse bristles; vestiture of dusky-brown scales. 

 Palpi short, stout, clavate, almost hidden by the clypeus, with a few coarse setae 

 and clothed with brown scales. Antennae plumose; last two joints long, rugose, 

 brown, with long ciliation, the others much shorter, but still elongate and 

 slender, brown with a narrow white ring; hairs of whorls very long, a whorl of 

 short hairs halfway between the whorls of long hairs ; tori large, yellow-brown. 

 Abdomen subcylindrical, more elongate than in the female, blunt at apex, the 

 claspers not prominent, without distinct lateral ciliation. Wings somewhat 

 narrower than those of the female, hyaline; venation and vestiture similar. 

 Claw formula, 0.0-0-0.0. 



Length : Body about 2.5 mm. ; wing 2.2 mm. 



Genitalia (plate 37, fig. 249) : Side-pieces short, about twice as long as wide, 

 tips conically rounded; basal lobe broad, low, with fine dense setge. Clasp- 

 filament moderate, swollen beyond middle, with a minute terminal claw. False 

 harpes rather broad, with revolute margins, tips rounded. False harpagones 

 divided into several portions, an inner broad plate forked at tip and several 

 small basal portions with recurved tips. 



Larva, Stage IV. Head rounded elliptical, widest through eyes; clypeus 

 rounded, protruding. Anteimge small, with a single hair near the base and a few 

 coarse spines at tip. Both pairs of dorsal head-hairs thickened, spiuose ; ante- 

 antennal tufts in threes. Air-tube about four times as long as wide, scarcely 

 tapering ; pecten not reaching middle, of twelve teeth, followed by a single tuft. 

 Lateral plate of eighth segment large, elliptical, with eight teeth on its pos- 

 terior border. Anal segment ringed by the plate. Ventral brush confined by 

 the chitinous ring. (The single specimen is in poor condition, so that the 

 structure of the teeth of the tube and lateral plate can not be made out.) 



Dr. Grabham found the larvae in permanent pools. He says that the larva 

 rests horizontally just under the surface-film. The habits are probably essen- 

 tially like those of Uranotcenia sappliirinus. 



Antilles ; possibly also the Gulf coast of United States. 



Havana, Cuba, May 14, 1902, November 10, 1903 (J. E. Taylor) ; Eock- 

 port, Jamaica, April, 1906 (M. Grabham) ; St. Thomas, West Indies, August, 

 1905 (A. Busck). 



