52 
Psyche 
[June 
clearly recognizable as ulcers. The second female was taken 
in association with six major workers. Of these one had 
moderately prominent ulcers on the cheeks, three had shal- 
low ulcers on the cheeks, one had small and very feeble 
ulcers and one was non-ulcerate. The two remaining females 
came from the same colony. In this colony were seven major 
workers. Three of these have a cephalic structure far more 
extreme than that of the type of ulcerosus. The ulcers on 
the cheeks of these fantastic insects are so deep that the 
bottom of the depression must be almost in contact with the 
Text-fig. 3. Camponotus ( Myrmaphaenus ) ulcerosus Wheeler, head of 
non-ulcerate major worker. The head has been tilted backwards slightly 
to show the anterior truncation as fully as possible. Scale as in text-fig. 1. 
gula. Each depression extends clear to the lateral border 
of the head, where it is bounded on the outside by a thin, 
vertical sheet of chitin. The sculpture of the depressions, the 
clypeus and the frontal lobes is extraordinarily rough and 
uneven, so much so that these parts have a peculiar shriv- 
elled or crumpled appearance (Text-fig. 1). The remaining 
four majors belonging to this colony closely approximate 
the condition found in the type of ulcerosus. There may be 
added here the cephalic characteristics of the majors taken 
