i8o Geese of Europe and Asia 



and are sometimes caught during the moult or as quite young goslings, and tamed. 

 I often met with them in this domesticated state, especially in the lower part of the valley of 

 the Selenga. On Tarei-Nor, in 1856, the first swan -geese showed themselves on April 3. 

 On the 1 8th, on Lake Ildza there were already many eggs, although by no means all the 

 geese bred there. Many of them kept in flocks during the whole summer. On the Middle 

 Amur the vanguard appeared earlier than in Mongolia, namely on March 28, 1858. On 

 April 4, in the Bureisk Hills on the Uril, geese were met with already paired. On the 

 Tunkinsk plateau in the spring of 1858 they appeared much later; although in that year all 

 the birds at that great elevation were late in their arrival, and the swan-geese, which are 

 generally not numerous, did not put in an appearance till the end of April. In previous 

 years, according to the natives, they were more common in this locality. On May 27, 1856, 

 the natives brought me swan-geese which showed the first signs of moulting ; and by the 

 first week of August the moulting was completed on Tarei-Nor. By August 12 the geese 

 had already concentrated in large camps, and their noise and cries were then unceasing. 

 They rested by preference on salt pools, over which they hovered from time to time. On 

 September 2 the majority of the swan-geese left Tarei-Nor, on the 4th there were but few 

 remaining, and by the 7th all were gone. In the Burei Hills I noted that the first left on 

 August 28, and the last on September 2. On the frontier of Mongolia the first eggs were 

 found on April 15; these being always of less size than those of the grey-lags which nest 

 there. The figure given by Thienemann agrees with the smallest example among those 

 brought home by myself. Usually the eggs are pure white, but some are stained all over 

 with grey dirt which cannot be washed off. The structure of the shell is subject to the same 

 variations as in the eggs of the grey-lag. They are often coarse-grained, but sometimes the 

 grains are less prominent and less close together, while at other times their surface is 

 comparatively smooth." 



This description of the eggs of the swan-goose does not agree with one by Mr. 

 Gobel, 1 based on 20 examples, in which " the structure of the shell of the egg of the 

 swan-goose ,: is said to be " smooth and shows a crystalline character, in which it 

 approaches that of the shell of the eggs of Bewick's swan." 



According to the same observer, these dimensions are as follows : — 



Max. breadth 59 mm. ( = 2.32 in.), with 85.5 mm. length ( = 3.28 in.), and 15 12 cgrm. weight (Sidemi). 



59 » ( = 2.32 » ), 

 Min. 2 „ 5 3 „ ( = 2.08 „ ), 

 Max. length 89.5 „ ( = 3.52 „ ), 

 Min. „ 76 „ (=2.99 



Max. weight 1590 cgrm., 

 Min. „ 1 176 „ 



Mean breadth 56.6 mm. ( = 2.22 in.); max. breadth 59 mm. ( = 2.32 in.); min. breadth 53 mm. ( = 2.08 in.). 

 „ length 81.6 „ ( = 3.21 „); „ length 82.5 „ ( = 3.24 /); „ length 76 „ ( = 2.99,,). 

 „ weight 1423 cgrm. ; „ weight 1590 cgrm.; „ weight 1 176 cgrm. 



Przewalski writes concerning this goose as follows : — 3 



" On the lakes and swamps of the valley of the Lefu, of all the geese the one 



1 Mistakes in the determination of eggs are very frequent, especially if the eggs are supplied by natives, so that it is more than 

 probable that Dr. Radde's description refers partly to eggs of other species. 



2 In one account we find the diameter less, namely = 5 r mm. ( = 2 in.), but it is very probable that the variations in this respect will 

 prove greater with larger material. 



3 Putesh. v Ussur. Kraye, 1870, p. 220. 



»> /' 



81 



( = 3-i8 „ ), 



53 



15 12 



,, 



33 



33 



76 „ 



( = 2.99 „ ), 



35 



? 



,, 



11 



(Kulussutai). 



58 „ 



breadth ( = 2.28 „ ), 



)3 



1572 



,, 



13 



(Sidemi). 



53-5 „ 



( = 2.10 „ ), 



7) 



I I76 



33 



53 



(Kulussutai). 



56 „ 



( = 2.20 „ ), 



53 



84 mm. 



length 



( = 



: 3.30 in.). 



53-5 „ 



( = 2.10 „ ), 



33 



7^ „ 



55 



( = 



: 2.99 „ ). 



