75 [Vol. xxxiii. 



and lengthy period to attain their full development; hence 

 for several successive moults a gradually increasing number 

 of feathers, showing in varying degrees an admixture of adult 

 and immature coloration, is met with/' 



Mr. Rothschild also made remarks on the correct name 

 of Montagu's Harrier, and exhibited several copies of Albin's 

 'Natural History of Birds' to show the great diversity in 

 the coloration of the plates. He said : — 



" After the time of Linnaeus the synonymy of the Hen- 

 Harrier and Montagu's Harrier became much confused, 

 owing to both species having been given a number of 

 additional names by more recent authors. The error in 

 the use of Linnseus's name ' Falco pygargus ^ was first 

 perpetuated by Naumann in 1822, when he applied it to 

 the Hen Harrier. The late Dr. Sharpe pointed out this 

 mistake in 1874 by drawing attention to the fact that 

 Linnaeus had founded his F. pygargus on Albin's ' Ring 

 Tail/ and that the plate in the ' Natural History of Birds ' 

 [vol. ii. pi. v. (1734)] undoubtedly represented a male of 

 Montagu's Harrier. While working out the correct names 

 of these Harriers for the new B. O. U. 'List of British 

 Birds,' Mr. W. L. Sclater drew my attention to the plate of 

 the ' Ring Tail ' in the copy of Albin's work in the Tweeddale 

 Library, and said that he could not see in what way it con- 

 firmed Dr. Sharpens statement. I agreed with him that the 

 figure certainly resembled nothing I had ever seen ; but, on 

 comparing my own copy, I found, to my astonishment, that 

 the coloration of the plates in the two books was totally 

 different. I then, together with Mr. Iredale, looked up 

 the copy in the Zoological Library at the Natural History 

 Museum, and found that the plate of the ' Ring Tail ' agreed 

 with that in my copy. It should be noted that Albin's work 

 in the Museum Library is a first-edition, while those in the 

 Tweeddale and in my own library are second-edition copies. 

 It is almost certain that Linnaeus took his description of 

 F. pygargus from a first-edition copy, in which the plate is 



«2 



