A nomenclature of colors for naturalists : and compendium of useful knowledge for ornithologists (1886)
Ridgway, Robert, 1850-1929, Wetmore, Alexander, 1886-1978 former owner. DSI, John Wilson and Son, printer · Boston : Little, Brown and Company · leaf 142
I. Black. 2. Slate-Black 3.Blackish Slat. 4. Slate color 5. Slate-Gray. , 6. Gray. Gray. 8. Grav. 9..Gray 10. Gray;
Birds · Ornithology · Color
Internet Archive · Getty Research Institute · Public Domain Mark 1.0. Free to use for anything.
