190 
Psyche 
[September 
granular appearance. The sculpture just described is confined to the 
anterior half of the head. The frontal lobes are heavily shagreened, 
the middle of the occiput more feebly shagreened and the sides of 
the head and the occipital angles are smooth and shining. There 
are conspicuous circular punctures on the frontal lobes, smaller oval 
ones on the sides of the head and very small and obscure punctures on 
the occiput. No other North American species of Camponotus has 
a comparable cephalic sculpture and yogi may be recognized by this 
feature alone. 
There is nothing in Wheeler’s treatment of yogi more exasperat- 
ing than his statement that this species is related to Colohopsis. In 
1896 Emery listed the distinguishing features of Colohopsis (3). 
When Wheeler monographed our North American forms in 1904 
he repeated Emery’s criteria and added two of his own (4). Ac- 
cording to Wheeler’s summary the female and major worker of Colo- 
hopsis have a head in which the truncated portion is circular in outline 
and sharply separated from the remainder of the head (marginate). 
There are conspicuous, umbilicate punctures on the sides of the head 
immediately behind the truncation. The mandibles have an external 
ridge or angle which separates the anterior face from the equally 
large latero-ventral face. Medias are rare or lacking and the pupae 
are not enclosed in cocoons. Because of the limited type material of 
yogi Wheeler could not know that in this species medias are present 
and the larvae are enclosed in cocoons. Nor could he know anything 
about the structure cf the female. Nevertheless, Wheeler was aware 
that the truncated portion of the head of the major of yogi is neither 
circular in outline nor marginate. He was aware that there is no 
external ridge on the major’s mandible. Since he described the dense, 
granular, sculpture which obscures the foveolae on the sides of the 
head of the major of yogi , Wheeler must have realized that these 
foveolae are scarcely comparable to the distinct, umbilicate, punctures 
of the Colohopsis major. In short, not a single feature of the major 
of yogi agreed with the major of Colohopsis as that caste was defined 
by Wheeler in 1904. 
These contradictions are annoying but they are not inexplicable. 
Wheeler’s initial views on Colohopsis were based almost entirely on 
species in the truncatus-impressus complex, as were the views which 
Emery had expressed earlier. By 1907, due to the many identified 
exotics which he had received from Forel, Wheeler was prepared to 
expand his original views on Colohopsis. It is regrettable that when 
he described yogi Wheeler failed to make it clear that some of the 
Asiatic and South Pacific species assigned to Colohopsis are more 
