154 Dwicnt, Moult of Quatls and Grouse. Awa 
median coverts are not moulted until later, the postjuvenal moult 
overlapping in a measure the limited one succeeding it. The 
black tail tipped with white is acquired at the postnuptial moult, 
the median pair of rectrices being latest in development, the rest 
of the series all being renewed at nearly the same time. ‘There 
are fourteen black rectrices. The two central feathers usually 
reckoned as rectrices appear to be in the row of coverts which 
they certainly follow in their moult, developing white and being 
renewed, when they are renewed, at a later period than are the 
black rectrices. The rectrices are moulted once in the year, the 
coverts often twice and a few of them three times. : 
Males and females in this intermediate plumage are not usually 
distinguishable, although the latter may be duller and with more 
tendency to barring, especially on the breast. A female scarcely 
full grown (Amer. Mus. No. 26173, Labrador, August 27) has as- 
sumed much of the preliminary plumage and is already beginning 
to show a few white feathers of the supplementary stage. Some 
body feathers of the juvenal stage are retained, including a few 
parti-colored ones on the inner margin of the sternal bands; the 
third primary is brown and also one feather of the alula. The tail 
is perhaps one quarter grown. New white feathers are growing 
systematically upon the abdomen, legs and toes, the points of first 
development for the toes being each joint. Two other birds (L. B. 
Bishop, No. 4503,?, and No. 4506, , Yukon Delta, Alaska, Aug- 
ust 28) are at about the same stage, but have assumed a few 
reddish feathers, chiefly on the breast. The first and second 
primaries have lost almost all traces of immaturity, the third has 
not been replaced and is brown, the fourth is only one half grown, 
and the fifth merely shows the remains of its sheath. At about 
the eighteenth remex partly grown feathers will be found, and the 
rest of the series is not yet renewed, but an exact count is ex- 
tremely difficult in all dried and distorted wings. Worn parti- 
colored feathers occur on the sternal bands adjacent to the ventral 
wedge, which is beginning to be clothed with pure white feathers. 
replacing yellowish ones, but these variegated feathers will be re- 
newed when the moult just beginning at the anterior part of the 
sternal bands reaches them, as will the external barred buff feath- 
ers that sweep backward over the flanks. The advance of the 
