eee | DwicuHt, Moult of North American Shore Birds. 381 
imen (G. B. Sennett, No. 3685, 2, March 28, Texas) may also 
be cited. The full plumage may not be acquired until early in 
May. 
Another species that has the same sequence of moults and plum- 
ages as the Sanderling, is the Dunlin which may well be con- 
sidered along with its North American representative. 
DuNLIN ( 7ringa alpina ). 
RED-BACKED SANDPIPER ( 7ringa alpina pacifica ). 
zr. Natal Down. The chick above has rusty and golden brown 
and black mottling, with small white dots. The mixed colors are 
due to banded down filaments or neossoptiles and the spotting to 
subterminal white areas. Below, including cheeks and forehead, 
the neossoptiles are buffy white, a dusky loral and postocular 
streak and a fainter malar one. 
2. Juvenal Plumage acquired bya complete postnatal moult. 
It is not generally known that birds in this plumage are quite 
heavily spotted below with black, the back with reddish and buff 
edgings, and a buff wash on the throat, so that they much 
resemble adults in breeding dress. I have examined several 
July and August birds from Alaska, a perfectly typical one, still 
retaining a little down on the head and neck being (U.S. Nat. 
Mus. No. 88881, August 3, Pt. Barrow, Alaska). 
3. First Winter Plumage acquired by a partial postjuvenal 
moult involving the body plumage, sometimes all, and sometimes 
part of the tertiaries, a few of the wing-coverts but neither the 
remiges nor rectrices. The gray plumage, white below, is assumed, 
scarcely distinguishable from adults in winter dress, but the cen- 
tral part of the dorsal feathers is usually paler than in adults, like- 
wise the gray shaft-streaks of the throat and sides. Left-over 
juvenal feathers are often found, and the black-spotted ones of the 
lower parts become faded and worn and may easily be mistaken 
for those of the adult. This plumage is fully assumed by October, 
as shown by many specimens from many localities, numerous 
November and December birds showing little evidence of further 
moult, viz.: Am. Mus. Nat. Hist. No. 69813, ¢, October 16, New 
