_Plumages._--The downy young red-backed is much paler and more buffy than that of the least sandpiper. The crown, back, wings, and thighs are variegated with brownish black, "ochraceous tawny" and "hazel," except at the base of the down on the back, there is no rich, deep brown; the above parts are quite thickly sprinkled, especially on the back, with minute, round spots, terminal tufts of pale buff; a distinct stripe of these nearly encircles the posterior half of the crown. The black of the crown extends nearly to the bill and there is a black loral stripe; the rest of the head and a band across the lower throat are "warm buff." The rest of the under parts are white. The nape is a grizzly mixture of dull buff and dusky. The juvenal plumage, as seen in Alaska in August, is strikingly handsome and quite distinctive. The feathers of the crown are dusky, edged with "ochraceous tawny"; the sides of the head and nape are "drab-gray," streaked with dusky; the feathers of the back are black, broadly edged with three colors in different areas, "ochraceous tawny," "hazel," and buffy white; the scapulars are black, edged with "light ochraceous buff"; the wing coverts are gray, tipped with pale buff; the rump and upper tail coverts are "hair brown" to "drab"; the breast is tinged with grayish and pale buff and streaked with dusky; the throat and rest of the under parts are white, conspicuously and more or less heavily spotted with dusky on the sides of the belly. This beautiful plumage is worn for only a short time and is molted before the birds leave their northern breeding grounds. The postjuvenal molt begins in August and is generally finished before October; it involves nearly all of the body plumage, nearly all of the scapulars, and some of the tertials, but not the rump, upper tail coverts, or flight feathers. In first winter plumage young birds are much like adults, but the ashy brown upper parts are usually somewhat paler, and they can always be recognized by the juvenal wing coverts and a few retained scapulars and tertials. A partial prenuptial molt, similar to that of the adult, produces a first nuptial plumage, in which young birds can be distinguished only by the retained juvenal wing coverts. In fresh plumage the black belly patch is veiled with white tips, which soon wear away and leave this area clear black. The first postnuptial molt of young birds and the corresponding molt of adults produce adult winter plumages. The molt is complete and begins in July or even late in June; the wings are apparently molted first in July, and are entirely renewed before the birds start to migrate; the body molt begins in August and lasts through September; there are usually traces of the old nuptial plumage left when the birds arrive here on migration. The partial prenuptial molt of adults comes in April and May and involves the body plumage, but not all the scapulars or rump or wing coverts.