554 GEOLOGICAL SURVEY OF THE TERRITORIES. 
EXPLANATION OF PLATE XX. 
Fig. 1. dpus newberryi, 9 , first foot. 
Fig. 2. Apus equalis, 9, first foot. 
Fig. 3. Apus longicaudatus, 9 , first foot. 
Fic. 4. Apus longicaudatus, Z, first foot. 
