'298 RET. W. HIIfCKS ON CTGNFS PASSMOEI. 



Further observations on Cygnus Passmori and C. buccinator. 

 By the Eev. W. Hincks, F.L.S. 



[Bead June 6, 1867.] 



Toronto, May 19, 1867. 



Mt note of April 10, 1864, published in the Journal along 

 with my paper on Cygnus Passmori, although intended to leave 

 the question undecided, would doubtless be considered to favour 

 the opinion that the supposed species is no more than a younger 

 and less-developed form of C. buccinator. 



I was not, indeed, myself satisfied with that opinion, which 

 set aside all my observed distinctive marks except that taken 

 from the sternum, and assumed that, because specimens were 

 procured indicating progressive changes in the appearance of 

 this part, all these changes could be reduced to one series ; but it 

 was my duty to report the facts which came to my knowledge ; 

 and for the moment these seemed to be at least reconcilable with 

 the notion of only one species. 



I have since taken every opportunity of obtaining further 

 materials for judging, and as the result of the past winter's ob- 

 servations I can lay before the Society such additional facts as 

 may, I think, enable us to settle the question. 



I have now before me six sterna of our northern swans, the 

 the comparative size and external appearance of each of the birds 

 being also known to me. One of these belongs to the original 

 specimen named by me C. Passmori, the stuffed skin of which 

 now forms part of the collection of Western Canadian birds sent 

 by the Board of Arts and Manufactures of Western Canada to 

 the Paris Exhibition. Two others are those which formed the 

 subject of my note of April 10, 1864, being successive states, 

 both of them with less enlargement of the trachea than in the 

 first specimen, but otherwise corresponding with C, Passtnori, of 

 which they are doubtless younger specimens. The series of 

 changes in these three suggested the idea of a progress of deve- 

 lopment which might be thought to terminate in the very re- 

 markable sternum and trachea which I described as properly be- 

 longing to G. buccinator. 



At that time I had but one specimen of this curious form, 

 which belonged to a full-grown male Trumpeter, and I had not 

 seen what I could be sure was the young of the Trumpeter, to 

 ascertain its agreement or otherwise with my supposed species, 

 I was thus, perhaps, too hasty (though, it now appears, substan- 



