Mergus castorStillImageDrawing depicting: Mergus castorLayout study traced from 0868a, but as a female and a young male, very rough, with color added; extensive general notes on color, measurements and weights; at top: "Jany. 10th 1854"; "See over." Published plate quite different from these drawings.ku-gould:19231https://digital.lib.ku.edu/ku-gould/19231Gould 0868bOrnithologyOrnithological illustrationelectronicimage/tiffThis work is free of known copyright restrictions.