296 THE BIRDS OF HELIGOLAND 



neck passes into olive grey, whereas in S. proregulus these parts 

 are pure whitish, with a tinge of lemon yellow. 



The rump only, and the bands on the wings, are of nearly the 

 same colour as in the Siberian species. 



If a row of specimens of the one species be placed side by 

 side with a row of the other, the differences become really very 

 striking, both on the upper and lower sides of the birds. In this 

 case, however, as in so many other instances in this family, the 

 measurements of the flight-feathers offer the most indisputable 

 proof of the specific distinctness of the two forms. In S. prore- 

 gulus the second flight-feather is equal to the eighth; in the 

 Indian form to the tenth. In S. proregulus the third, fourth, 

 and fifth flight-feathers are of equal length, and form the tip of 

 the wing ; while, in the Indian form (S. humei), the tip is formed by 

 the fourth, fifth, and sixth, the third being -12 in. (3 mm.) shorter. 

 In 8. proregulus the second flight-feather is only - 23 in. (6 mm.) 

 shorter than the tip of the wing ; in the Indian form it is '39 in. 

 (10 mm.) shorter, and in consequence almost of equal length to 

 the longest posterior flight-feather, whereas in S. proregulus 

 it projects from about -23 to -27 in. (6 to 7 mm.) beyond the 

 latter. 



It is remarkable that not only is the similar difference in 

 coloration existing between S. superciliosa and its southern 

 relative repeated in S. proregulus and its southern form, but is 

 accompanied by an almost similar difference in the structural 

 formation of the wing. 



The breeding range of the present species appears to extend 

 as far as the eastern portions of central Asia. 



111. Crowned Willow Warbler [GEHAUBTER LAUBVOGEL]. 

 SYLVIA CORONATA, Temminck. 1 



Phylloscopus coronatui. Seebohm, Cat. of Birds of Brit. Mus., v. 49. 



This beautifully marked Warbler, whose home is in south-eastern 

 Siberia and Japan, has been caught once on this island, having 

 been obtained by Reyiners on the 4th of October 1843. At that 

 time the few birds I possessed served merely as parlour decora- 

 tions, as I had not yet begun to collect systematically ; and though 

 I felt greatly interested in this pretty bird, especially as Reymers 

 described it as never having been seen before on the island, I did 

 not feel inclined to pay the high price which he asked for it. I 



1 Phylloscopus coronatus (Temminck and Schlegel). 



