4 BEV. W. HINCKS ON CTGNUS PASSMOKI. 



tinct in G. Passmori, and the sinuses at each side of the posterior 

 extremity, which are deep and well defined in G. Passmori, being 

 very obscure in G. buccinator, as if the large swelling over the 

 trachea interfered with them. 



I add a few comparative measurements, and have endeavoured 

 faithfully, though rudely, to represent by figures some points of 

 comparison amongst the North American species of Gygnus. 



The weight of G. Passmori was .18 lbs., whilst that of a medium 

 specimen of G. huccinator which was compared with it was 30 lbs. 



inches. 



The length, from the tip of the beak to the J G. Passmori 51 



end of the tail, of ....... I C. huccinator 60 



Length of the head in the line of the f G. Passmori 7^ 



meeting of the mandibles [ G. huccinator 9| 



-r, , ^ ,, . ,. f. , 1 1 1 ^ G. Passmori 5 



Back 01 the eye to tip ol the beak 



G. hticcinator 5| 



Hind point of the nostril to tip of the f C. Passmori 2 



beak [ C. huccinator 3 



C. Passmori 8 



Length of sternum 



G. buccinator 



'3 



ITT- ij.1 ii J. • J i G. Passmori 4 



Width near the posterior end • • • • i ^ , . . , 



I C. buccinator 4|^ 



Greatest width of the heart-shaped eleva- ^ 



tion on the posterior portion of the >- G. huccinator 3-^ 



sternum in J 



Length of the same 4 



The value of some of these diiferences can only be determined by 

 repeated trials, but they furnish materials not undeserving of 

 notice. 



I believe the ferruginous colour on the head and upper portion 

 of the neck of C. huccinator is constant and very characteristic of 

 the species, and it is probably more widely diffused and conspicuous 

 in the younger birds ; yet our smaller bird has scarcely any of the 

 ferruginous tint, which is replaced by very pale grey, whUst the 

 wing-feathers, which are pure white in C. huccinator, are tipped in 

 G. Passmori with a faint fawn-colour. I have mentioned the angular 

 forehead of G. Passmori ; whilst that of C. buccinator has the promi- 

 nence wider and curved, and in G.Americanus it is a much shallower 

 and more open curve. I wish to observe this character in the 

 fresh specimen, lest it should be in any degree affected by the 

 taxidermist's proceedings ; but I am disposed to confide in it. 



