The Ants of the Baltic Amber. 



139 



- k 



I believe that Mayr was mistaken in regarding C. mengei and 

 igneus as distinct species. The only difference which he could detect 

 between them was in the shape of the thorax, C. mengei having the 

 dorsal surface convex in profile and passing over into the declivity 

 of the epinotum without 

 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 epinotum forms a 

 straight line, and the base 

 and declivity of the epi- 

 notum meet at a distinct 

 angle. These differences 

 are clearly'- shown in 

 Mayr's figures (PI. 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 TFigs. Q(^), 

 and that the angle from 

 which the specimen is 

 seen may make the thorax 

 look more convex than it 



really is. Moreover, an examination of Mayr's three types of C. mengei 

 in the Geolog. Inst. Koenigsberg Coll. (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. mengei. 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 me7igei Mayr. 



SL) Worker B 18996, with angular epinotum ; 



b) worker with more rounded epinotum. 



