Hab. Aru.
Gen. Podomyrma, Smith.
Head oblong in the female, rather wider than the thorax; in the worker subovate and much wider; eyes small, ovate and placed about the middle at the sides of the head; antennæ geniculated, the scape about two thirds of the length of the flagellum which is clavate, the club three-jointed; the mandibles stout and dentate; the labial palpi 3-jointed; the maxillary palpi 4-jointed. Thorax, oblong-ovate in the female, in the worker transverse in front and narrowed behind with the metathorax bidentate; the anterior wings with one elongate marginal cell and two submarginal cells, the second extending to the apex of the wing; the legs stout, the femora incrassate; abdomen ovate, the peduncle with two nodes.
The insects included in this genus are undoubtedly most nearly allied to those belonging to the genus Myrmecina; but, excepting that they agree in having the same number of joints in the palpi, they have little resemblance to each other. With the exception of the genus Myrmecia, these are the largest insects in the subfamily Myrmicidæ; and all the species are distinguished by their remarkably thickened femora and margined thorax: we are unacquainted with the males.
1. Podomyrma femorata. P. ferruginea; capite oblongo, obliquè striato, thorace abdomineque lævibus nitidis; alis subhyalinis fusco-nebulosis; femoribus valdè incrassatis, basi tenuissimis, femoribus posticis infrà compressis.
Female. Length 8 lines. Rufo-testaceous; the mandibles and anterior margin of the face black, the inner margin of the mandibles rufo-piceous and armed with six short stout teeth, the apical tooth largest. The head oblong, slightly narrowed posteriorly and emarginate behind, longitudinally striated, the striæ diverging from the centre at the anterior ocellus; at half the distance between the posterior ocelli and the margin of the vertex the striæ are transverse. Thorax smooth and shining, with scattered fulvous hairs; the wings fusco-hyaline, with a dark fuscous stain occupying the marginal cell and traversing the course of all the nervures; the legs with the femora much incrassated, the posterior pair compressed beneath into a flattened process or keel. Abdomen ovate, smooth, shining, and with a scattered fulvous pubescence; the first node of the petiole rounded in front, narrowed and truncate behind, with a large compressed tooth beneath; the second node subglobose.
Worker major. Length 4 lines. Ferruginous, entirely smooth and shining; the thorax, legs, and abdomen more or less obscure, the femora being usually rufo-piceous; the mandibles striated with their margins black. Thorax nearly flat above, very slightly convex with the sides margined, the anterior margin slightly rounded, the lateral angles produced into small acute spines; a deep strangulation at the base of the metathorax, a little before which the lateral margins are produced into an angular tooth, the metathorax with two short acute spines; the femora thickly incrassate. Abdomen ovate.
Hab. Aru.
2. Podomyrma striata. P. ferruginea; capite thoraceque longitudinaliter striatis, femoribus valdè incrassatis, basi tenuissimis.
Worker. Length 3 lines. Rufo-ferruginous with the abdomen obscure, becoming blackish at the apex, the head coarsely striated, with a central portion from the insertion of the antennæ to the hinder margin of the vertex delicately so; the mandibles striated, with the teeth on their inner margin black. Thorax rugose-striate, the anterior lateral angles dentate, the metathorax without spines; the femora thickly incrassate and greatly attenuated at their base. Abdomen ovate, smooth and shining; the nodes of the petiole rugose.