The Genus _Semnotes_ contains two very large and handsome crane-flies, both of which were originally described by Westwood. They are giants of the family, with a large thorax, and swollen abdomen narrowed slightly into a waist, coming out broad and rounded to the tip; the general colour is bright yellow mottled with black, with semitransparent wings. _Semnotes ducalis_ has dark markings on the wing, and is the rarer species. It is recorded by Westwood from North Australia, and by Skuse from Manly, N.S.W. _S. imperatoria_ is found in Victoria, about Sydney and the Blue Mountains N.S.W.; it is slightly larger than the former, and can be easily distinguished by the very long tarsi, the plain wings, and the different markings on the body. Family 6. Soldier Flies. STRATIOMYIDAE. These are flat-bodied flies with narrow strongly veined wings; 3-jointed antennae; and the pronotum furnished with slender spines. Comstock has called them “Soldier Flies” on account of the bright coloured stripes with which many species are marked. The larvae of most of these flies live in decaying vegetable matter, but some are known to be carnivorous in their habits. _Neoexaireta spinigera_ is one of our commonest species, often to be found in the early summer months resting on the window pane with its broad hind legs flattened out; it is very easily captured. It is a slender shining black fly about 1 inch in length, with banded legs; the sides of the body fringed with white hairs, and the apical half of the wings clouded with black enclosing a small white blotch; the pronotum is furnished with four slender spines standing out from the hind margin. The larvae are usually found under damp rotting bark or decaying vegetable matter, and are elongate flattened brownish and distinctly segmented creatures, with narrow horny heads standing out in front like a stalk; they are sluggish creatures with very little movement. I figured and described a species (doubtfully) under the name of _Ephippium albitarsis_ in my “Entomology of the Grass-trees” (Pro. Linn. Soc. N.S.W. 1896) with somewhat similar larvae breeding in the decaying stems of these trees. The little black fly measures about ⅓ of an inch in length; it has white tarsi and dusky wings; the pronotum has the usual short spine on either side; and the legs are stout. _Odontomyia stylata_ is an elongate, broad, flattened, bronzy green fly with the outer edges of the abdomen light green; and the long pointed wings are folded down over the back; the head is very broad; the rounded thorax is long, furnished with two small spines behind the pronotum, and the abdomen is broadly rounded at the tip. It is a common rather large fly about ½ an inch in length, usually found resting on foliage in damp places. It has a wide range over Australia. In other parts of the world these flies are numerous, and about 1,000 species of the family have been described.