EXPLANATION TO PLATE VI. 



Fig. 1. Accipiter atricapillus, Wilson. American Goshawk. 



Fig. 2. Accipiter atricapillus striatulus, Ridgway. Western Goshawk. 



Pigs. 3, 4. Parabuteo unicinctus harrisi, Audubon. Harris's Hawk. 



Figs. 5. 6. Buteo borealis, Gmelin. Red-tailed Hawk. 



Figs. 7. 8. Buteo borealis calurus, Cassin. Western red-tailed Hawk. 



Fig. 9. Buteo lineatus elegans, Cassin. Red-bellied Hawk. 



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