"Coccygus americanus. Yellow-billed Cuckoo. Bill black, extensively yellow below and on the sides of upper mandible. Feet dark plumbeous. Above, satiny olive-gray. Below, pure white. Wings extensively cinnamon-rufous on inner webs of the quills. Central tail-feathers like the back; the rest black with large white tips, the outermost usually also edged with white. Very constant in color, the chief variation being in extent and intensity of the cinnamon on the wings, which sometimes shows through when the wings are closed, and even tinges the coverts. Young differ chiefly in having the white ends of the tail-feathers less trenchant and extensive, the black not so pure; this state approaches the condition of erthrophthalmus, but does not match it." Elliot Coues, 1884

Small Yellow-billed Cuckoo

"Coccygus americanus. Yellow-billed Cuckoo. Bill black, extensively yellow below and on the sides of…

"Coccygus americanus. Yellow-billed Cuckoo. Bill black, extensively yellow below and on the sides of upper mandible. Feet dark plumbeous. Above, satiny olive-gray. Below, pure white. Wings extensively cinnamon-rufous on inner webs of the quills. Central tail-feathers like the back; the rest black with large white tips, the outermost usually also edged with white. Very constant in color, the chief variation being in extent and intensity of the cinnamon on the wings, which sometimes shows through when the wings are closed, and even tinges the coverts. Young differ chiefly in having the white ends of the tail-feathers less trenchant and extensive, the black not so pure; this state approaches the condition of erthrophthalmus, but does not match it." Elliot Coues, 1884

Yellow-billed Cuckoo

"Coccygus americanus. Yellow-billed Cuckoo. Bill black, extensively yellow below and on the sides of…