Mr. Yarrell's Reply on the Discovery o/'Cygnus Bewickii. 167 



oxide (Ann. Phil. iii. 358) : and the mean taken is inclined 

 conformably. 



The insertion of any experiments of my own has been avoid- 

 ed, as needlessly swelling this paper, which proceeds on other 

 grounds, and is already too long. For the same reason, the 

 corresponding tables of oxides and acids are withheld ; but 

 if you find this deserving of publication, they can be forwarded 

 at a future time. I am yours, &c. 



Plymouth, April 10, 1830. John PridEAUX. 



XXVI. Reply to the Statement respecting the Discovery of 

 Cygnus Bewickii, published in the Phil. Mag. and Annals 

 for August. By W. Yarrell, Esq.. F.L.S. 



To the Editors of the Philosophical Magazine and Annals. 

 Gentlemen, 



A LTHOUGH anonymous accusations can have little in- 

 ^*- fluence with your readers, and might therefore safely be 

 treated with the neglect they merit; I yet, in self-defence, re- 

 quest insertion in your Magazine, of the following brief ob- 

 servations, in answer to a letter, addressed to you by a mem- 

 ber of the Natural History Society of Newcastle-upon-Tyne, 

 which appeared in your 44th Number, published at the com- 

 mencement of the present month. 



It is first necessary that I should justify the opinion I gave 

 by letter, 'that the distinctions described as existing in the parts 

 of two swans might be occasioned by "age, sex, or accidental 

 circumstances." For this purpose I shall quote, verbatim, the 

 description itself, as sent me in March 1829, at which time 

 the opinion was given. 



" A young man, of the name of , who has given con- 

 siderable attention to the ornithological part of Natural Hi- 

 story, has the breast- bone and trachea of the common wild 

 swan and of the new one ; and our joint observations are as 

 follows : 



"The new species has eight ribs, and the old one only seven ; 

 the two specimens of the breast-bone are the same length, ten 

 inches from the extremity of the merry- thought (where it joins 

 to the elbow of the neck-bone) to the other end of the breast- 

 bone ; but whereas in the common wild swan the bend of the 

 trachea takes place seven inches from the extremity of the 

 merry-thought; in the new one it is only four inches and a 

 half. In the common wild swan the wind-pipe on entering 

 the breast-bone is nearly round ; in the new kind, so much flat- 

 tened as to equal half an inch by a quarter. In the com- 

 mon 



