The sub-family PONERINAE includes many large or medium sized ants with elongated bodies furnished with only one constricted segment or node at the base of the abdomen, and the latter terminating in a powerful sting. The larvae are enclosed in stout silken cocoons. The Genus _Myrmecia_ contains most of our largest typical species peculiar to Australia, popularly known as “bull-dog ants,” “inchmen,” or “jumpers”; about 34 species have been described, some of which have a very wide range. The “Jumper,” _Myrmecia albo-cincta_, forms its nest under the shelter of a low bush; it is a low mound with an opening on the summit, and another on the side level with the ground; when disturbed these ants come rushing out like a pack of dogs with a series of short jumps, and attack everything they meet. It is one of the smaller species, about ½ an inch in length, of a uniform black colour, with only the front and hind portion of the thorax brownish red to yellow. _Myrmecia forficata_ is our large red and black “bull-dog ant,” with a very extended range like the previous one from Victoria to Queensland. They measure up to 1 inch in length, and are of a uniform dull red, except the eyes and abdomen, which are black. They live in rather large colonies up to 200 in number, digging deep circular shafts or irregular chambers under logs; when away from the latter, they form regular domed mounds over the nests, which in summer contain the large, elongated, oval, brown sacks enclosing the pupae, and often a number of winged males and females; the former with small heads and jaws, the latter with jaws as large or larger than those of the workers. _Myrmecia gulosa_ is of a lighter red colour, with the tip of the abdomen black. _M. tarsata_ is our common black bull-dog ant, with yellow jaws, and antennae and tips of the legs reddish brown; it has a great habit of hunting up and down the larger tree trunks, and drops to the ground at the least alarm; when disturbed in the nest, if the first two or three are captured, the others will usually retreat down their burrows, and not show fight like the other species. Sharp notes the bull-dog as forming large mounds (Cambridge Natural History); but I think he was misinformed, as the nests of the Mound Ant, _Iridomyrmex detectus_, are often confounded with these ants. The Genus _Odontomachus_ contains a number of curious slender black ants with large heads and long projecting jaws; they are more tropical in their range, but _O. ruficeps_ and its varieties are found from the Darling River N.S. Wales through Queensland to North Australia.