138 
Psyche 
[December 
Pheidologeton affinis (Jerdon) 
(PL 6, figs. 17-18) 
Sexual (?) larva: Length straight from end to end 
8 mm; length from head to anus through spiracles about 
12 mm. Voluminous, plump and turgid, bean-shaped. Head 
exceedingly minute, on the ventral surface near the anterior 
end. Mandibles somewhat smaller; apical tooth vestigial; 
only one medial tooth. Otherwise similar to diversiis worker 
larva. (Material studied: six larvae from Dutch New 
Guinea; hairs broken off.) 
Genus Oligoviyrmex Mayr 
Short and very stout; prothorax forming a short, very 
stout neck which is bent ventrally to a right angle; dorsal 
profile C-shaped, ventral sinuate; diameter greatest at ab- 
dominal somites IV and v. Body hairs short and moderately 
numerous. Of two types : ( 1) deeply bifid, with the branches 
curling away from each other, the most abundant type, 
absent from the ventral surface of the thorax; (2) a few on 
the ventral surface, with short-bifid tip. Head hairs few, 
short, varying in arrangement and shape. Labrum small 
and subrectangular ; posterior surface sparsely spinulose. 
Mandibles with a long slender apical tooth which is curved 
medially; a large subapical tooth on the anterior surface; 
an acute medial tooth arising from the posterior surface 
near the middle of the mandible; one or two additional 
medial teeth may be present. Maxillary and labial palps 
each represented by a cluster of four sensilla; galea a low 
knob. 
Oligomyrmex parvicornis Forel 
(PI. 6, figs. 1-7) 
Mature worker larva: Length about 1.5 mm. Short 
and very stout; prothorax forming a short, very stout neck 
which is bent ventrally to a right angle; dorsal profile C- 
shaped, ventral sinuate; diameter greatest at abdominal 
somites iv-v. Anus ventral, with a posterior lip. Segmenta- 
tion indistinct. Mesothoracic spiracle a third larger than 
the metathoracic and first abdominal (which are equal), 
the others exceedingly minute (one-third the size of the 
mesothoracic). Integument of midventral surface of thorax 
