216 OBSERVATIONS ON THE CHANGES OF 



old feather was remaining on that part ; and in another this process was 

 going on among the feathers on the breast and sides. In the remainder 

 there were a few young feathers, but no regular moult. 



Sylvia petechia^ Yellow Red-Poll Warbler. This species I was ex- 

 tremely anxious to examine, in reference to this subject. The differ- 

 ence of its plumage in winter and summer is as striking as that of 

 Sylvia coronata. It however becomes yellow olive in spring, whilst 

 the other becomes blue, streaked with black, with a yellow spot on its 

 rump and crown. The Sylvia petechia has been described under two 

 names, that of the above and Sylvia palmarum, by Bonaparte and Au- 

 dubon ; the latter recently acknowledged his error. I obtained of this 

 species twenty-four specimens. Every individual was moulting ex- 

 tensively. The new feathers came out at once in summer dress, leav- 

 ing not a shadow of doubt on my mind that this bird receives its 

 bright colours from a change of feathers, and not from a change of co- 

 lours in the old feathers. 



Sylvia pensilis, Yellow Throated Warbler. This is one of the small 

 number of the species of this large genus that breeds in Carolina. Its 

 note was first heard on the 16th of March. Obtained, at various 

 times, thirteen specimens. In every instance the whole of the yellow 

 on the throat was replaced by young feathers just pushing forward, 

 and in several individuals moulting was general over other parts of the 

 body. The above observations apply equally to Sylvia trichas, Mary- 

 land Yellow Throat, of which I inspected about five specimens. 



Fringilla tristis, American Goldfinch. This was one of the birds 

 referred to by Mr Ord, as a proof of the correctness of his theory, that 

 birds moult but once a year. Although this species is common in 

 Carolina in winter, feeding on the seeds of the long moss (Tillandsia 

 usnoides) that hangs in festoons from the limbs of our venerable live 

 oaks {Quercus virens), and at a later period on the imported, but very 

 common chick weed {Alsina media), it generally leaves us for the 

 north early in March, and, no doubt, undergoes its changes of plumage 

 in spring in the immediate vicinity of Philadelphia. This bird had 

 left us for about two weeks, but was driven back to this vicinity in conse- 

 quence of a succession of cold days; and from the 16th to the 22d of 

 March I had an opportunity of obtaining forty specimens. On the 



