346 PERCY SLADEN TRUST EXPEDITION 
41. Drosophila nasuta, n. sp. (Fig. 30 and Plate 20, fig. 32). 
A somewhat large pale orange form with well-marked facial knob. 
Head. [yes densely covered with short bristly hairs: hind eye-angles projecting a 
little behind plane of head. Top view :—frons light-orange, not shining (see below “front 
view ”), eye-margins very slightly greyer in tone. No triangle; the areas between eye- 
margins and ocellar area ending off in rounded margins on the vertex. A very narrow 
and shallow groove runs from the front ocellus to the forehead. Ocelli red. Front f. o. 
a little diverging, hind the same; the small bristle row from latter begins with a stout 
bristle nearly between the two f. o. (instead of as usual nearly opposite the front), the 
continuing small bristles only number four or five. Slightly convergent 1. v., divergent 
0. v., p. v. crossed at tips inserted just on curve of vertex. Oc. long and divergent, 
inserted outside the line joining the ocelli and just behind the front one. A few small 
bristles on the ocellar area and behind it; two tiny crossed pairs by the central furrow 
just over the forehead. Front view :—the large second joints just separate at base: just 
below them starts the snout which widens gradually till it joms the swollen upper lip ; 
two deep fovese formed for antenne by the frons and snout. Face all orange: in this 

Fig. 30. Drosophila nasuta, n. sp. x 30. 
view (with a side light) the frons of the male is seen to be quite silvery. Side view 
(Plate 20, fig. 32) —second antennal joint orange with fine bristles, especially side ; one 
upper and one front spine. Third joint somewhat darkened distally and inside ; arista 
with long straight rays, seven on top, one terminal, three below; the inner row exceptionally 
well-developed, of some eight to ten rays. A stout vibrissa, with following row of 
diminishing bristles on lower eye-margin; three or four bristles on hind jowl; post- 
orbital row well seen, strongest and bent upward behind v. b. Palpi rather clubbed at 
end, orange and bristly as is the tongue. Be. 
Thorax. Dorsum non-shining orange, very uniformly covered with small bristles, 
forming eight acrostichal rows before the d. c. lines and six between the two pairs of d. c. 
Humeri much paler, as is a stripe from them to the wing base; this is succeeded by a dark 
orange stripe from prothorax to.halters: the rest is pale yellow orange. Two h., n. p., 
presut., three over wing and another (post a.) just above scutellar base; large and two 
small st. pl. The scutellum is flattened with well-marked margin ; terminal b. crossed 
about two-thirds down, smaller side ones inserted on the edge and slightly convergent. 
Wings, Fig. 30, somewhat yellowish with brownish veins, Halters orange. Legs all 
