se and pubescent. Abdomen globose,
shining, and closely punctured; the scale of the petiole transverse
above, produced into an acute spine on each side, the upper margin
finely serrated, the lateral margins narrowed to their base, and having
two or three small sharp spines.

_Hab._ Aru.

7. POLYRHACHIS SCUTULATUS. _P._ niger, fortiter politus et lucidus,
metathorace petiolique squamula dente longo curvato acuto in latere
utroque, pedibus nigro-ferrugineis.

_Worker._ Length 2-3/4 lines. Black and very smooth and shining; the
legs dark ferruginous. Thorax: the disk expanded, slightly convex above,
with the margins acute and curving upwards; the anterior margin
transverse, rather wider than the head, with the lateral angles slightly
curved forwards, and very acute; the lateral margins of the prothorax
curved backwards and inwards; the margins of the mesothorax are rounded;
the pro- and mesothorax highly polished above, forming an
escutcheon-shaped disk; the metathorax opake, and sprinkled with a few
short glittering hairs, armed posteriorly with two long very acute
spines, divergent and directed backwards. Abdomen globose; the scale of
the petiole with two long curved acute spines, directed backwards to the
curve of the abdomen.

_Hab._ Aru.

8. POLYRHACHIS MUCRONATUS. _P._ laevis, nitidus, niger; thorace spinis
duabus crassis compressis acutis postice armato.

_Worker._ Length 2-1/2 lines. Black, smooth, and shining, very
delicately and indistinctly aciculate; the antennae beneath and the tibiae
and femora obscurely ferruginous, the anterior and intermediate tibiae
brightest; the apex of the mandibles ferruginous. Thorax transverse in
front, or very slightly curved, with the lateral angles acute; the
thorax is rounded above, and not margined at the sides; the metathorax
armed with two long, stout, acute compressed spines; the spines
divergent, as well as two on the scale of the petiole, which are long
and very acute. Abdomen globose.

_Hab._ Aru.

9. POLYRHACHIS GEOMETRICUS. _P._ niger; antennarum apice, tibiis
tarsorumque apice ferrugineis, thorace circulariter striato.

_Worker._ Length 2 lines. Black; the apical joints of the flagellum, the
anterior legs, the anterior and intermediate tibiae, and the apical
joints of the tarsi pale ferruginous; the extreme base of the anterior
tarsi black. Thorax rounded above, not margined, gradually narrowed
posteriorly; the prothorax of the same width as the head, its l