1722 
DIPTERA OF AUSTRALIA, 
cuneiformly narrowed towards the base, the anterior branch 
slightly bent posteriorly at its extreme tip in the Fork of the 
fifth longitudinal vein very long, its base situated some distance 
before the sub-costal cross-vein. Sixth longitudinal vein some- 
what sinuous, joining the margin beyond the posterior cross-vein, 
in the 9 opposite the supernumerary cross-vein (PI. XL., fig. 1). 
As far as I am aware only eiglit species of this very distinct 
genus hav'e been hitherto described — one from North and another 
from South America, one from the West Indies, four from 
Southern Asia and the Eastern Isles, and one from Amur, 
Northern Asia. 
191. Megarrhina speciosa, sp.n. (W. Macleay, MSS.). 
(J. — Length of antenn* O'lGO inch ... 4-06 millimetres. 
Expanse of wings 0'330 x 0'060 ... 8 39 xL54 
Size of body 0-440 x 0-080 ... 11-17 x 2-02 
Antennfe brown, a little more than half the length of the 
palpi ; basal joint black, with hoary reflections : second joint more 
than twice the length of the third, ornamented with some beau- 
tifully iridescent scales, the whorl of very long hairs situated about 
^ from the apex. Head covered with brilliant margaritaceous 
scales, chiefly reflecting green ; in a certain light appearing brown 
^vdth a bright pale greenish line round the hinder border of the 
eyes. Proboscis (0-300 in.) somewhat longer than the palpi 
(0-285 in.), deep metallic blue, with a purplish reflection before 
the bend, brown beyond. Palpi deep metallic blue, with 
jiurplish reflections, the third joint ringed with golden- 
yellow at the apex (this is much more distinct underneath), 
and the fourth joint with a broader ring of the same 
V)eyond the middle. Thorax brown, the lateral margins and 
prothorax densely covered with pale greenish scales, the latter 
with long brown hairs ; hinder margin and scutellum richly 
adorned with brilliantly iridescent scales and long brown hairs ; 
pleurae with a naked brown stripe from the origin of the wings to 
the scale-like prothoracic projection, below this densely covered 
