16 WHEELER— ANTS FROM BORNEO AND LUZON [Pe 
Castaneous; head somewhat paler and more reddish; mandibles and 
femora honey-yellow; antenne, fore tibix, tarsi and tips of femora yellow- 
ish brown, the dilated middle and hind tibize darker brown. Wings brown- 
ish hyaline, with brown veins and apterostigma. 
Described from a single specimen taken by Mr. G. E. Bryant on Mt. 
Matang, West Sarawak, Borneo, and sent me by my friend Mr. Horace 
Donisthorpe. 
This species is very distinct from the only other known member 
of the genus, M. binghami. Forel from the Thaungyin Valley, 
Tenasserim, as I find by comparison with a cotype kindly given me 
by Prof. Forel several years ago. The Bornean specimen can 
hardly be the hitherto unknown female of binghamz, as the worker 
of the latter is larger (5 mm.), has only eleven mandibular teeth, 
with two minute denticles between the penultimate and terminal 
long teeth, the legs are decidedly longer, the middle and hind tibize 
are much less incrassated, the clypeus is of a very different shape, 
the surface of the body is much smoother and the color much paler. 
Dimorphomyrmex luzonensis sp. nov. 
Figure 4. 
Female. Length about 8.5 mm. 
Body slender; head oblong, excluding the mandibles, a little more 
than one and one half times as long as broad, as broad in front as behind, 
but distinctly narrowed in the middle, with nearly straight posterior border 
and convex cheeks; in profile nearly two and one half times as long as high, 
flattened above and below. Mandibles convex above and on the sides, 
with six coarse teeth. Clypeus broad, extending to the lateral borders of 
the head, with a flat median and two convex lateral portions; the former 
not projecting as far forward as the latter. Frontal area and groove dis- 
tinct, the former large and triangular, the latter extending to the anterior 
ocellus. Frontal carine straight, diverging behind, more than twice as 
far apart as the distance of each from the lateral border of the head, and 
extending to the middle of the anterior orbits. Eyes large, nearly one third 
as long as the head, a little further from the anterior border of the clypeus 
than from the occipital border of the head, subelliptical, with slightly 
concave medial and convex lateral orbits. Ocelli well developed, situated 
very far forward so that the posterior pair are nearly on a line connecting 
