ORTHOPODOMYIA SIGNITER 889 



of white scales on lateral margins of segments ; second segment with a median 

 basal triangular white patch; first segment white scaled and with many long, 

 fine pale hairs ; venter white scaled, with apical segmental black bands becom- 

 ing successively broader towards tip; lateral cilia and those on hind margins 

 of segments coarse and rather long, black. 



Wings moderate, hyaline ; scales of veins large and abundant, clavate, partly 

 narrow and partly broad ; color of scales mostly dusky brown, white scales in- 

 termixed ; bases of first and auxiliary vein heavily white scaled for a short dis- 

 tance; sixth vein white scaled from base nearly to its middle; a white transverse 

 patch in the region of the cross-veins extending across second, third, and fourth 

 veins and upper branch of fifth ; second marginal cell long, nearly twice as long 

 as its petiole ; base of second posterior cell in line with base of second marginal 

 cell ; basal cross-vein about its own length behind anterior cross- vein. Halteres 

 pale, the knobs large and with white scales. 



Legs long and rather slender; vestiture dark-brown and white; femora and 

 tibiae with scattered white scales ; knees and the apices of middle and hind tibine 

 white ; middle and hind tarsi white marked ; on the middle tarsi the base and 

 apex of the first joint and the base of the second are narrowly white ringed; 

 hind tarsi with fifth segment entirely white above, the others white at bases and 

 apices, very broadly on first segment, narrowest on fourth segment. Claw 

 formula, 0.0-0.0-0.0. 



Length : Body 3.5 to 4 mm. ; wing 3.5 to 4.5 mm. 



Male. Proboscis straight, moderately long, rather stout, thickened towards 

 apex. Palpi long and very slender, straight, slightly exceeding the proboscis 

 in length, end of long joint and the following joint somewhat thickened and 

 with scattered moderately long bristles, densest about apex; vestiture dull 

 brown with numerous white scales intermixed, tending to form longitudinal 

 lines on long joint, a white ring at base of following joint. Antennae densely 

 plumose, rather long, last two joints long and slender, the others short, but 

 longer than usual in males, stout, subcylindrical, white with broad dark rings 

 at insertions of hair-whorls; hairs of whorls rather long, with a yellow- 

 brown silky luster; tori large, black, shining, with an oblique crest of white 

 scales above. Abdomen long, depressed, dorsal vestiture mostly of dusky black 

 scales; second segment with basal two-thirds white scaled; third segment 

 broadly white banded at base; succeeding segments with large lateral basal 

 patches which are joined by a basal band of dirty- whitish scales ; venter mostly 

 dull white scaled; lateral ciliation coarse, moderately long and abundant, 

 irregular, brown. Wings narrower than those of female, venation and vestiture 

 nearly the same ; the white patch near middle of wing less conspicuous than in 

 the female, sometimes almost obsolete. Claw formula, 1.0-1.0-0.0. 



Length : Body 3 to 4 mm. ; wing 3 to 3.5 mm. 



Genitalia (plate 36, fig. 238) : Side-pieces over twice as long as wide, tips 

 conically tapered ; a large rounded basal lobe bearing three stout spines besides 

 a covering of short hairs. Clasp-filament long and slender, slightly enlarged 

 basally and apically, bearing a terminally inserted, distally broadened spine. 

 Harpes concave, elliptical ; margins, especially at tip, revolute, a crown of three 

 spines at apex. Harpagones wanting. Unci plate-like, revolute, tips narrow 

 and curved. 



Larva, Stage IV (see the figures of the entire larva, stages III and IV, plates 

 80 and 81). Head rounded subquadrate, nearly straight on the sides, front 

 margin broadly arcuate. Antennae moderate, subcylindrical, swollen at base, 

 distinctly tapering, sharply narrowed at basal third at origin of tuft, which is 

 of about six feathered hairs; shaft smooth; two longer terminal hairs, two 

 short ones, and a small digit. Eyes small, rounded. Both pairs of dorsal head- 

 tufts multiple and long; ante-antennal tuft multiple but short. Mental plate 

 57 



