_Camponotus inflatus_ is the curious “honey ant” of Central Australia figured and described by Lubbock in his “Bees, Ants, and Wasps.” The naturalists on the Horn Exploring Expedition obtained a number of this and other species, described by me in the Zoology of this Expedition. The ordinary members of the “honey pot ants” are of the usual normal form, but certain individuals of each nest of these species are crammed with a honey secretion (probably obtained by the workers from aphids or psyllids), until the abdomen swells out of all proportion to the rest of the ant; the honey pot ants remain hanging about in the bottom of the nests like a number of bottles of honey, incapable of leaving the nest; the supply is probably used as food for the larvae. Spencer says that the blacks dig up these nests and look upon the “honey pots” as great luxuries. The honey is sweet with an acrid taste like the honey of our native bees. They are apparently common in Central Australia; Miss Ormerod sent me some from England which she had received from a correspondent at Kalgoorlie; and recently Mr. Field of Tennant’s Creek sent me a fine red species from the far north. _Camponotus claripes_, a smaller pale coloured species, generally makes its galleries at the base of a tree trunk, and has a very wide range from Victoria to North Queensland. I found the cocoons of this species in a nest at Howlong infested with full grown red velvet mites (_Trombidiidae_), which occupied the whole space. The Genus _Polyrhachis_ contains a number of black ants of fair size, most of which build their nests in dead logs, and live in rather large communities, but others form small nests by matting the foliage of trees together; the latter are confined to Queensland, and are generally smaller shining black forms. The true “wood ants” are more or less covered with bright metallic pubescence and fine hairs, and with the hind portion of the thorax and the node of the abdomen ornamented with a pair of slender spines. _Polyrhachis ornata_ is black, with the thorax and base of the spines richly tinted with gold; it comes from Queensland. _P. ammon_, ranging from Victoria to Queensland, is clothed with pale golden pubescence lightest on the head and thickest on the abdomen. _P. semi-aurata_ has both the head and thorax golden, with the abdomen smooth, black and shining. _P. laevior_ is one of the smaller tree nesting forms, and is smooth and shining without any metallic tints, and the thoracic and abdominal spines are very small. _P. turneri_, also a northern form, has the head golden, and large well developed spines. Family 14. Solitary Ants. MUTILLIDAE.