EXPLANATION TO PLATE IV. 



Figs. 1. 2. Corviis corax siniiatiis, Wagler. American Raven. 



Fig. :i Corvns corax principalis, Ridgway. Northern Raven. 



Figs. 4, .5, 6, 7. Oorvus cryiitoleucus, Couch. White-necked Raven. 



Figs. 8, 9. 10, 11, 12. Corvus americaniis, Andnbon. American Crow.' 



Figs. 13, 14. Corvus americanus floridanns, Baird. Florida Crow. 



Fig. 15. Corviis caurinus, Baird. Northwest Crow. 



Figs. In, 17. Corvtis ossifragns, Wilson. Fish Crow. 



'Pigs. 21, 2:3. Corvus americanus, Audubon. See Plate V. 



