collected near Aden by Col. J. W. Yerbury. 417 
6. Face yellow, with an ill-defined median black line ; it is almost 
perpendicular from the antennz to the upper mouth edge. The 
face and frons are clothed with rather abundant yellow pubescence ; 
the back of the head bears longer paler pubescence below ; the 
vertex is black about the ocelli, but greyish-yellow in front, and 
bears short black pubescence. Eyes touching for a small space. 
Antenne dull blackish, basal joints sometimes dull reddish ; arista 
yellowish-brown. 
Thorax black with five distinct yellow lines, the middle line 
being quite distinct though rather narrower than the others. 
Abdomen reddish-ochreous (“rothlichochergelb ” of Loew), dull ; 
the second segment has the base narrowly, and an incomplete wider 
dersal line, blackish ; the third and fourth segments bear an almost 
circular blackish dorsal spot near the base ; all the hindmargins of 
the segments show obscure signs of darkening ; genitalia brown, 
rather shining. 
Legs dull black, with the tips of the femora dull ochreous and 
more extensively so behind the hind femora; the anterior tibize 
are all dull obscure ochreous; while the hind tibiz have the base and 
a rather broad middle ring obscurely ochreous, and the two basal 
joints of the middle tarsi and the base of the front tarsi are similarly 
coloured, All the femora are thick, the middle pair being least so 
- and the hind pair most so ; the hind femora are not serrulate beneath, 
but bear black bristly hairs and a scabrous patch near the tip 
composed of short black bristles, while there.is the usual scabrous 
black patch at the base in front ; all the femora bear abundant soft 
yellow pubescence. Tibize all with abundant soft pubescence, mainly 
yellow but mixed with black ; hind tibiz dilated and curved, bearing 
long shaggy black pubescence beneath. ‘Tarsi all dilated, at any rate 
towards the tip, the hind pair bearing rather long shaggy black 
pubescence in front, and also bearing at the base beneath the peculiar 
knob-headed black hairs, which peculiar hairs can be traced, though 
very short, over all the sole of the basal joint. 
Wings slightly tinged with brown, dullish. Squame and halteres 
orange. 
Q. Similar but with shorter pubescence; frons narrow for a 
female, all brownish-yellow except on the shining bare space just 
above the antenne, its pubescence being all yellow except just about 
the ocelli. Abdomen less sharply marked, all the hindmargins 
being greyish glaucous, while the round black spot on the fourth 
segment has a tendency to spread out into two sloping darkened 
lines, of which there is some indication on the third segment ; the fifth 
segment is mainly ochreous yellow with an ill-defined shining black 
space about the middle of the hindmargin. Legs much paler, the 
