The Zoologist — February, 1868. 1081 



gull with the back and scapulars all lavender, as is the case with the 

 blackhead, these birds differing strikingly this way in their first 

 winter. The rump is much more lead-colour, as are also the greater 

 coverts of the secondaries. The remainder of the celestial surface, 

 tail and quills as in first plumage, but of course, as the year advances, 

 more faded. 



Terrestrial Surface. — Has been, all but the under wing and tail- 

 coverts, renewed by moult. Differs little but in the better quality of 

 the feathers, the greater purity of the white and the greater definity 

 and darkness of the markings. The base of the bill has changed to 

 green or livid flesh-colour, the feet also becoming greatly suffused 

 with that colour. 



No. 6, Link 3. First Spring. — I may say that since August there 

 has been almost an incessant dropping out and replacing by moult of 

 individual feathers ; after December this cannot be called a moult, for 

 from that time the bird seems to have some rest in its plumage, but 

 with April and May the same gradual moult begins again, extending 

 itself this time to the feathers that have not been affected before, 

 viz. the secondary coverts and the remaining brown feathers in the 

 back. 



No. 7. Second Summer (from a bird killed in June). Celestial 

 Surface. — Head and neck similar to the last winter. The entire back, 

 scapulars, rump, and a very large proportion of the lesser coverts of 

 the secondaries, the dark lavender of the adult, perhaps approaching 

 more the lead-colour of the kittiwake ; like that bird, too, the central 

 parts of these coverts have not moulted jet, and thus form a brown 

 bar through the wing. The tail and the wing-quills have not as yet 

 began to moult. 



Terrestrial Surface.— The dark markings have considerably 

 decreased. The bill is greenish lead-colour at the base ; the feet also 

 of this colour. The irides and the orbits brown. The mouth yellow 

 flesh-colour. 



No. 8, Link 4. Second Summer and Autumn Moult. — The general 

 moult begins in July, though sometimes earlier, and extends into 

 October; by November it is always perfected. All the plumage is 

 renewed at this moult, even that which came in the spring past. The 

 primary quills and the tail are generally the last feathers assumed, 

 the primaries commencing at the tenth quill, — in other words at the 

 carpus,— renewing in succession to the first, which is frequently 

 incipient when all the rest are matured ; the tail generally comes all 



SECOND SERIES — VOL. III. l 



