Vor. II, Pr. II] WHEELER—COCOS ISLAND ANTS 307 
lowish than the thorax, knees slightly infuscated, posterior bor- 
ders of the gastric segments very narrowly yellowish. 
Worker mmor. Length 4.5-5 mm. 
Differing from the worker major mainly in the structure of 
the head and in coloration. The head is somewhat longer than 
broad but the posterior corners are more rounded and the occi- 
pital border is straight, the clypeus is broader than long, the 
antennal scapes extend half their length beyond the occipital 
border, the eyes are large and distinctly convex. Thorax much 
like that of the worker major but higher and somewhat more 
gibbous in the mesonotal region and with the epinotal angle 
less distinct and more rounded and the declivity more sloping. 
Sculpture and pilosity much as in the worker major but the 
surface of thorax, petiole and gaster and of the head behind the 
clypeus decidedly more shining and the puncturation of all 
these parts finer, denser and more indistinct. 
The erect hairs are glistening white, somewhat more abund- 
ant and conspicuous than in the worker major and the pubes- 
cence longer and distinct on the whole dorsal surface of the 
head. 
Head between and behind the eyes, thorax, petiole and gaster 
dark brown, the antennal funiculi byond the first joint and the 
knees distinctly infuscated, anterior portion of the head, includ- 
ing the mandibles yellowish, tips and teeth of the mandibles 
brown. 
Worker media. Length 5.5-6 mm. 
Intermediate in structure between the major and minor 
worker but with the coloration, sculpture and pilosity of the 
former., 
Described from six major workers, three mediz and six 
minor workers taken in November, 1905, by Dr. Williams. 
The worker major resembles the corresponding phase of C. 
novogrenadensis Mayr in size and in the structure of the head 
and body, but the sculpture, pilosity and color are very different, 
the eyes are much larger, the antennal scapes somewhat longer, 
the thorax longer and less convex in the mesoépinotal region, 
etc. The worker minor bears a strange resemblance to the 
worker minor of C. biolleyi but can be distinguished by its 
