MiddendorfFs Goose 



107 



to repeat that the black, which at times extends somewhat backwards from the nail on 

 to the anterior part of the orange ring, must by no means be taken for the beginning of 

 the black nail of the upper mandible. With careful scrutiny it is easier to ascertain 

 where the posterior edge of the nail runs in the specimens in which it is less clearly marked 

 than in those in which it is sharply defined. 



In not a single example of the Siberian form have I seen a white border along 

 the base of the bill, although I admit the possibility of this appearing in some 

 cases, but only to a very limited degree, that is to say, with separate plumules. 

 In the majority of cases the number of teeth on each side of the upper mandible in 

 the Siberian race varies between 26 and 30, but examples occur in which they do 

 not exceed 24 in number. I give below a table of measurements of the bill of this 

 goose, showing the limitations within which I have hitherto been able to follow the 

 fluctuations in the proportion of the oilmen-length of the upper mandible, the greatest 

 depth of the visible part of the lower, and the number of teeth along the edges of the 

 upper mandible. Unfortunately, in the majority of cases the sex of the birds was not 

 noted on the skins. 



Sex. 



Culraen. 



Depth of lower 

 mandible. 



Number of teeth, 

 upper mandible. 





0* 



? 

 ? 



? 



? 



? 



? 



?6 



? 



?? 



?9 



6 



juv. 



mm. in. 

 82 - 3.22 



74- 2.91 



75 = 2 -95 



75 = 2.95 

 83-3.26 

 78-3.07 

 82 - 3.22 

 83-3.26 

 78-3.07 



76 - 2.99 

 74- 2.91 



77 = 3-o3 

 64 = 2.51 



mm. in. 

 12 = О.47 

 Ю-О.39 

 Ю-О.39 



II. 3-0.44 



9 = °-35 



10.5 -О.41 



IO-O.39 

 9 = 0.35 



9 = 0.35 

 8-О.31 



3° 

 24 



26 



28 



3° 



28 



29 



28 

 28 



25 



? E. Siberia ; probably Taimyr peninsula. 



Kamchatka ; Voznesensky, " Giet " ; head rusty. 



R. Moniero. Czewakinski ; head brown rusty. 



R. Tunka, Radde ; head very rusty. 



Bering Isl. ; Grebnicki ; head brown. 



? Taimyr peninsula. 



Kamchatka ; Voznesensky. 



Radde ; Amur j head and neck bay. 



Yakutsk ; M. A. Menzbier coll. 



Adycha (Yana) ; Bunge; head dark coffee. 



Yakutsk ; M. A. Menzbier coll. ; head dark coffee. 



Yakutsk ; M. A. Menzbier coll. ; head coffee-brown. 



Su-Chou ; Brothers Grum-Grzymailo expedition. 



Young Birds 



Of these I know nothing, except the above-mentioned female from Su-Chou, which 

 I regard as a bird in first plumage or a yearling, but not more. The plumage is duller 

 and all the feathers are narrower than in adults. 



In some specimens, which apparently are not quite mature, there are a few white 

 plumules on the chin, and in one the whole mental angle is white; but even in this 

 example there are no traces of white plumules at the base of the bill. 



As to the young in down, I have no information. 



The dimensions of the adult birds are compiled from authors who have written 

 on this goose, and from the material at my own disposal. 



Total length 



Spread 



Wing . 



Culmen 



Depth of bill at base 



Breadth of bill at base 



Breadth of bill (middle of nares) 



up to 



circa 



780-930 mm. (= 30.07-36.60 in.). 

 1390 mm. (= 54.70 in.). 

 450-505 mm. (17.70-19.80 in.). 

 74-83 mm. ( = 2.90-3.26 in.). 

 36-38 mm. (= 1.41-1.49 in.). 

 3 1 mm. ( = 1.22 in.). 

 25 mm. (0.98 in.). 



