1372 
DIPTERA OP AUSTRALIA, 
2- + 9-joints, P. m'naticornis has 2- + 8-joints in the (J, and 2-+9- 
joints in the P. erehea 2- + 8 joints in both sexes, and lastly 
P. dimidiata 2- + 6- also in both sexes. In all these cases the 
first joint of the flagellum (or as Macquarts puts it the “ third 
joint” of the antennee) is larger than any other, and the terminal 
joint is always extremely small and nipple-shaped. As Macquart 
was the original describer of P. dimidiata, he should have drawn 
attention to the deficiency of joints. Possibly describers are two 
apt sometimes to take things for granted. The palpi ai’e much 
longer than the antenme. Abdomen with eight segments. 
The number of known species belonging to this genus is small. 
It does not appear to be represented in Europe, and the majority 
of examples have been described from South America, Asia and 
Eastern Isles. 
183. Plecia amplipenxis, sp.n. (PI. xxxix, fig. 3.) 
— Length of antennse 0 045 inch ... 1T3 millimetres. 
Expanse of wings 0*390 x 0'140 ... 9*89 x 3*55 
Size of body 0*300 x 0*070 ... 7*62 x 1*77 
Antennae the length of the head, dull black, densely covei'ed 
with a minute pubescence, 2- + 9-jointed, all the joints furnished 
with very short verticils. Head, ocelli, and palpi dull black. 
Eyes dull black or purplish-black, beset with minute hairs. 
Thorax, pleurae, pectus, scutellum, and metathorax entirely of a 
uniform bright ochreous or fei*ruginous-ochreous, opaque, with no 
pubescence. Halteres long, black, the base of the stem ochreous 
or ferruginous-ochreous, with a minute pubescence. Abdomen 
about the width and more than twice the length of the thorax, 
black, almost opaque, somewhat shining, densely clothed with 
short black hairs ; ovipositor short. Legs black, except the 
coxae which are brown, nitidous, densely pubescent ; tibial spurs 
black ; pul villi yellow. Wings longer than the body, smoky- 
brown inclining to fuscous, darker antei*iorly ; stigma tolerably 
