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Psyche 
[Vol. 92 
body devoid of hairs. In amber of the Middle Eocene (Claiborne) of 
Malvern, Arkansas. Collected by R. H. Mapes (see Saunders et al., 
1974). Deposited in the Museum of Comparative Zoology. 
The species is named for Frank M. Carpenter in recognition of his 
pioneering work on the fossil ants of North America. 
Two comments on the generic diagnosis are required. First, the 
conical shape of the last gastric segment as seen from two obliquely 
dorsal views leaves little doubt that the Protrechina carpenteri holo- 
type possessed an acidopore, the most distinctive trait characteriz- 
ing the Formicinae as a whole. Unfortunately, while grinding the 
