2 CO DwiGHT, Plumage-Cycles. LjiSy 



to the breeding season, becomes a true nuptial plumage, simple or 

 compound according as the moult is complete or incomplete. It 

 is therefore obvious that there are three plumages belonging espe- 

 cially to adult birds, instead of the two usually recognized if adher- 

 ence be given to the seasonal idea. The three are the annual 

 (possibly annuo-nuptial would express it better), the nuptial and 

 the non-nuptial. As for the special protective plumages of the 

 Ducks and Ptarmigans, they might be called tutelar (Lat. tut- 

 elaris), and they seem to be the result of a complete postnuptial 

 moult, on the heels of which follows so quickly the always incom- 

 plete posttutelar, that the latter seems to be a continuation of the 

 former. The Ducks, however, pass most of the year in the com- 

 pound annual plumage, resulting from the two moults, while the 

 Ptarmigans on the other hand acquire a compound non-nuptial 

 dress that is further compounded for the breeding season by 

 a prenuptial moult lacking in the Ducks. These then are the 

 plumages and moults peculiar to birds in their second or later 

 years, that is after the first postnuptial moult, and it will now be 

 easier to understand those of the young bird that at each successive 

 moult approaches more nearly to the ultimate adult plumage. 



The first plumage of the young bird is the natal, a name 

 applicable to the rudimentary feathers of the first generation 

 known as neossoptiles or neoptilcs. The Megapodiida; are said 

 to lose this plumage before the bird leaves the e.gg, while its 

 growth both before and after hatching may be observed in many 

 familiar species. Most water birds, like the Pygopodes, the 

 Anatidse or the Limicolae, and among land birds the Gallinae, are 

 thickly covered with this down-like plumage, while its scantiness 

 is marked in most land birds like the Passeres or Columbae. In 

 some families like the Picidre or Trochilidai it is absent. At most, 

 the natal plumage is worn for only a brief period and is completely 

 lost by what may be considered as a postnatal moult, although 

 this consists chiefiy of loss by abrasion of the neossoptiles from the 

 tips of the succeeding feathers to which they are attached. There 

 is no cessation of feather growth as after an ordinary moult, but the 

 calamus of the neossoptile is continued into the tip of the defini- 

 tive feather or teleoptile which follows. There is, however, feather 

 loss of the first generation and feather gain of the second, the two 

 essential constituents of a moult. 



