THE MAGAZINE 



OF 



NATURAL HISTORY. 



AUGUST, 1836. 



ORIGINAL COMMUNICATIONS. 



Art. L Observations on the various seasonal and other external 

 Changes which regularly take place in Birds, more particularly 

 in those which occur in Britain ; with Remarks on their great 

 Importance in indicating the true Affinities of Species; and upon 

 the Natural System of Arrangement. By Edward Blyth, Esq. 



Numerous as are the writers in this department of zoology ; 

 assiduously as the study of birds is cultivated in all parts of 

 the civilised world ; and talented as are many of the naturalists 

 and close observers who devote their more particular attention 

 to this branch ; it still appears to me, that the numerous and 

 very diversified regular changes of plumage and general ex- 

 ternal appearance, observable in this interesting subclass of 

 animals, have been hitherto very greatly and strangely over- 

 looked, and that, in consequence, the many valuable physio- 

 logical inferences deducible from their investigation have been 

 quite lost to the purposes of science and of classification. 



It is true that many naturalists have in so far attended 

 to the mutations of plumage which some particular species 

 undergo, as that they are able at once to recognise them in 

 every livery they assume ; but the exact ages, and seasons, of 

 moulting; the precise nature of the general, or only partial, 

 change that is undergone, and the various accordances and 

 dissimilarities observable between the changes of distinct 

 species ; the endless characters of agreement and difference, 

 so important in pointing out affinities, in showing what ap- 

 parently similar races could never be brought to hybridise 

 together ; would seem to have been passed over as unworthy 

 of notice, as undeserving of a particular investigation. 



The subject is both extensive and complicated, and involves 

 a number of other recondite enquiries. I could have wished 

 that some naturalist better qualified than myself had taken it 



Vol. IX. — No. 64. g g 



