EXPLANATION TO PLATE X. 



Fig. 1. Falco rusticolus obsoletus, Gmelin. Black Gyrfalcon. 



Figs. 2, 3. Falco mexicanus, Schlegel. Prairie Falcon. 



Figs. 4, 8. Falco columbarius, Linnaeus. Pigeon Hawk. 



Figs. 5, 6, T. Falco peregrinus anatum, Bonaparte. Duck Hawk. 



Pigs. 9, 10. Falco fusco-ccerulescens, Vieillot. Aplomado Falcon; 

 Figs. 11, 12, 13,11, 15, 16. Falco sparverius, Linnaeus. American Sparrow Hawk. 



Pig. 17. Pandion haliaetus carolinensis, Gmelin. American Osprey. 



