Mareca americana. Duck. Obtained March 12, 1911. January 14, 1912. New and old primary coverts mixed. Three of former together. Distal primary covert old, three following new, then old ones (in one wing). Otherwise the bird appears to be in fresh feather. I seem unable to find other old worn feathers. February 11, 1912. Looks in good plumage but is moulting breast feathers without a doubt. One wing seems to lack primary coverts, exposing white basal shafts of primaries. March 10, 1912. Seems to be through moulting. The white basal shafts of primaries appear still white as though primary coverts were lacking. Aside from three or four feathers, apparently from the drake of this species, there were none on the pond freshly moulted, so I take it that the moult is about over in all seven individuals. April 7, 1912. Aside from wear, there seems to be no change. May 5, 1912. Aside from wear, there seems to be no change.