1720 
DIPTERA. OF AUSTRALIA, 
those situated in close vicinity to stagnant water and marshy 
places, wdiere the insects may be frequently observed drinking. 
I must take this opportunity of gratefully acknowledging the 
assistance derived from the Hon. William Macleay’s MSS., which 
w’ere freely handed to me for my use ; also the help from Drs. J. 
and T. L. Bancroft and Mr. Henry Tryon, of Brisbane ; Mr. A. 
G. Hamilton, of Mt. Kembla, Illawarra ; Mr. De Meyrick, of 
Penrith ; and Mi. George Masters, in obtaining for me valuable 
material for description. 
Genus 1. Megarrhixa, Desv. 
Megarrhina, Desvoidy, Essai sur les Culicides, Mem. Soc. d’Hist. 
Nat. de Paris, III. 1827, p. 412 ; Macquart, Dipteres Exotiques, 
Vol. I. 1838, p. 32, pi. 1, fig. 1. 
Proboscis bent downwards about the middle of its length ; 
in the ^ almost the length of the body, in the ^ a little shorter. 
Palpi in the ^ a little longer than the proboscis ; first joint short ; 
second, third, and fourth elongate, cylindrical, of equal length 
except the second, which is a little shorter ; in the 9 of rather 
less length than the proboscis, with five cylindrical joints of nearly 
equal length. Antennas in the ^ with bushy plume.s, the second 
joint a little elongate ; in the 9 the joints elongate, with a few 
long hairs at the base. Prothorax projecting from each side in 
the form of a scale ; bordered with hairs in the naked in the 
9 . Abdomen : the last three segments bordered laterally wdth 
hairs in the the copulatory organ accompanied by tw'o append- 
ages terminating in a point. Wings : first marginal cell very 
small ; transverse veins very remote from the petiolated cells. 
Obs . — The above is derived partly from Macquart’s synoptical 
table on p. 29, and partly from the additional characters 
enumerated by him on p. 32, drawn from the sexes of M. 
hcemorrhoidalis, the type of this genus. I would add the 
following observations wdth reference to the species hereafter 
described, more particularly as it does not correspond in every 
particular with Macquart’s description or figure. 
