210 BRITISH BIRDS. 



in our birds from the nestling to maturity, and from 

 season to season. 



It is extraordinary how little we know, notwithstanding 

 all the present-day knowledge of British birds, of the 

 Sequence of Plumages and the methods whereby these 

 plumages are acquired in even our commonest species. 

 In his " Dictionary of Birds " (p. 595) the late Professor 

 Newton deplored the neglect of this important work by 

 ornithologists, and remarked that there was little 

 advance in our knowledge of the subject since the 

 observations of Herr W. Meves were published in 1854. 



In 1900, Dr. Jonathan Dwight, Jun., published an 

 important monograph on " The Sequence of Plumages 

 and Moults of the Passerine Birds of New York " 

 (Annals N. Y. Acad. Set., Vol. XIII., pp. 73-360, October 

 31st, 1900). This, so far as. I know, is the only con- 

 nected and complete account of the cycle of plumages 

 of any birds, though the extremely careful descriptions 

 of many of the plumages of our birds by William 

 Macgillivray, and the equally careful descriptions of 

 Naumann, must not pass unnoticed, since these re- 

 nowned ornithologists made a most diligent and pains- 

 taking beginning to what was in their time undoubtedly 

 an impossible task to complete, owing to insufficient 

 material. 



The difficulties of obtaining material sufficiently com- 

 plete to work out the changes of plumage in any one 

 species are considerable. In most collections moulting 

 specimens are conspicuous by their absence ; few people 

 take the trouble to determine, by a simple examination of 

 the skull when an autumn bird is being skinned, whether 

 it is young or old ; many skins bear no adequate 

 data regarding sex or date, and in describing plumages it 

 is above all necessary to know by some other guide than 

 the plumage itself, whether the bird is old or young, 

 male or female. In the case of summer migrants, again, 

 few African travellers seem to take the trouble to collect 

 the " common " British species in their winter-quarters, 



