eee | Dwicnt, Moult of North American Shore Birds. 373 
winter specimens with the outer primaries much more worn than 
the inner seem to point to the checking of moult in some cases 
and this failure to moult at the proper time is much more com- 
mon in body feathers. 
Few birds taken on the North Atlantic coast show moult of the 
remiges in progress, but many species in collections, those in 
my own collection represented by specimens studied while fresh, 
show renewal of the body feathers by the postnuptial moult which, 
as proved by southern specimens, is usually completed in August 
or September. The adults of species with a postjuvenal moult 
begin moulting earlier than young birds, a fact which may 
account in part for the migration of males earlier than the females 
and young, just asin Passerine species. My experience for years 
has been that the birds seen in July and early August are largely 
adults, and intelligent gunners everywhere tell the same story. 
Later than October it is not easy to distinguish old from young 
unless the latter retain here and there distinctive feathers of the 
juvenal plumage, or the former retain a few feathers of the nuptial 
dress. A few tell-tale feathers remaining until a later period of 
moult are invaluable in fixing age, for plumage differences 
between young and old in winter are slight and inconstant as a 
rule, although more marked in some species than in others. 
The amount of wear shown by the plumage varies with the 
individual, and black feathers outwear those of any other color. 
The primaries and secondaries show so little wear that even 
the microscope will not demonstrate how much newer one feather 
is than another without other evidence, but the finding of growing 
feathers often confirms the testimony of worn plumage, and it is 
upon the testimony of such ‘blood-feathers,’ as they have felici- 
tously been called, that all my conclusions are based. 
There is abundant evidence that adults and young both under- 
go a prenuptial moult which certainly involves the body plumage of 
both ; in young birds of many species the moult is complete, except 
perhaps in the case of some females; in adults it does not seem 
to include the remiges nor the rectrices. 
Comparatively few specimens show winter moult of the remiges, 
but among them may be mentioned the following, viz., Crymophilus 
fulicarius (U. S. Nat. Mus. No. 86423, February 21, Lower 
