120 A DECADE OP AUSTRALIAN THYNNIDEOUS INSECTS. 
eniarginate at its anterior margin, exposing the labruin, which is 
3 ^elIow, and with its anterior edge slightly bilobed; the mandibles 
are yellow, with the tips black. The antennm are short and black 
(scarcely measuring 3 lines in length) ; the outer edge of the 
maxillas is clothed with long white hairs. The collar is black, with 
an entire rather naiTow yellow margin. The mesonotum is black 
with a yellow spot in the middle, and a small one on each side 
behind the wing-scales, which are also yellow ; the scutellum bears 
a yellow conical spot; the apex directed towards the head : behind 
this is a narrow transverse yellow lunule, and two lateral yellow 
dashes; and the metathorax bears two oblique yellow lines, extend¬ 
ing to the outer posterior angles ; the sides of the thorax, beneath 
the insertion of the wings, are also spotted with yellow. The 
abdomen is elongate-ovate and depressed, broadest across the middle, 
black and shining; the five anterior segments bearing a large 
lunular yellow spot on each side, inclosing a short black transverse 
line which, in the fifth segment, unites with the black-ground 
colour of the segment; the sixth segment bears two minute and 
slender yellow lunules. The body beneath is clothed with gray 
pubescence ; the coxse black, with yellow stripes; and the abdomen 
black, each of the intermediate segments with two slender yellow 
lunules ; the terminal segment is entire, and rounded at the tip; 
the legs are entirely chesnut red, and the wings stained with 
yellowish brown. 
Inhabits King George’s Sound. In Mus. Westw. 
THYNNUS (AGRTOMYIA?) MARGINALIS, 
(Plate 76, fig. 3.) 
T. uiger griseo subpiibescens, clypeo ocullsque (in parte inferiori) albido tenuissimo 
marginatis ; abdominis scgmcntis quinque basalibus lunula tcnuissima albida utrinque in 
margine postico notatis, pedibus duobus anticis castaneis, posticis duobus nigris. 
Long. corp. lin. 7^. Expans. alar. lin. 12. 
The head and thorax of this species are black, thickly but finely 
punctured, and not shining ; the latter elongate, with the scutellum 
rather elevated, convex, and less strongly punctured ; the clypeus 
is rather short, convex, black, slightly carinated down the 
middle and truncate at the tip, with a slender white margin 
extending as far as the eyes, to which it also forms a slender 
margin about as high as the insertion of the antennae. The back 
part of the head is marked with two obscure red spots. The 
antennae are black, the tips being, however, broken off in my 
