The Ants of the Baltic Amber. 
139 
I believe that Mayr was mistaken in regarding C. meng ei and 
igneus as distinct species. The only difference which he conld detect 
between them w T as in the shape of the thorax, C. menget having the 
dorsal surface convex in profile and passing over into the declivity 
of the epinotum withont 
a distinct angle, whereas 
in C. igneus the thorax, 
from the anterior border 
of the mesonotum to the 
posterior end of the base 
of the epinotnm forms a 
straight line, and the base 
and declivity of the epi- 
notnm meet at a distinct 
angle. These differences 
are clearly shown in 
Mayr’s figures (PL I, 
Figs. 8 und 9). Now the 
examination of numerous 
specimens shows that 
these differences are 
somewhat exaggerated in 
Mayr’s figures ; that there 
is considerable Variation 
in the convexity of the 
thorax, as indicated in 
my two figures (Figs. 66), 
and that the angle from 
which the specimen is 
seen maymake the thorax 
look more convex than it 
really is. Moreover, an examination of Mayr’s three types of C. meng ei 
in the Geolog. Inst. Koenigsberg Coli. (209/29, 392/51 and 10234/627) 
shows that these actually have the thoracic outline of C. igneus (Fig. 9) 
and not of his Fig. 8 which represents C. mengeil Of the 103 specimens 
I have examined, all but two have the thoracic structure of C. igneus , 
while the two approach rather closely the outline of C. menget . This 
outline is still more closely approximated in Emery’s figure of what he 
regarded as a pseudogyne of C. igneus , although he was not sure 
that it belonged to this species. Perhaps Mayr may have seen such 
a specimen and have drawn his figure from it. Although I have not 
Fig. 66. Camponotus mengei Mayr. 
a) Worker B 18996, with angular epinotum; 
b) worker with more rounded epinotum. 
