488 BRITISH BIRDS. 



Genus ANSER. 



The Geese were included by Linnaeus with the Swans and the Ducks in 

 the genus Anas, both in the tenth edition of the ' Systema Naturae/ pub- 

 lished in 1758, and in the twelfth edition of the same work published in 

 1766. In Brisson's ' Ornithologia/ which appeared in the meantime (in 

 1760), the genus Anas is split into two genera, Anser and Anas, the former 

 including the Swans, Geese, Eider Duck, and Muscovy Duck, and the 

 latter the smaller Ducks. Bechstein appears to be the first ornithologist 

 who restricted the genus Anser to the Geese. In his ' Ornithologisches 

 Taschenbuch/ ii. p. 404, published in 1803, the characters of the restricted 

 genus are described. The Grey-lag Goose, A. cinereus, being the Anas 

 anser of Linnseus, is the type. 



The Geese resemble the Swans, but differ from the Ducks in having 

 the tarsus covered in front as well as at the back and sides with small 

 hexagonal reticulations. From the Swans they are distinguished by their 

 longer legs, shorter necks, and feathered lores. 



Geese resemble Swans and differ from most of the Ducks not merely in 

 the fact that they only moult once in the year, so that the summer and 

 winter plumage are similar, but also in the peculiarity that there is little 

 or no difference in the colour of the plumage of the two sexes. Geese pair 

 for life, and although the gander does not assist in incubation, he takes an 

 active part in the care and defence of the young. Incubation lasts about 

 four weeks ; the young are born covered with down, and are able to run 

 and swim a few hours afterwards. After about six. weeks the wing- and 

 tail-feathers begin to appear, and in a few weeks more they have 

 completed their first plumage and are able to fly. In September their 

 first moult begins, and proceeds slowly until December, when they are in 

 the plumage of birds of the year, which only differs from that of the adult 

 in some of the feathers, especially the wing-coverts, retaining signs of 

 immaturity by having pale margins, and in the fact that the quill-feathers 

 and most or all of the tail-feathers are not moulted until the second 

 autumn, when the bird is rather more than a year old. As might be 

 expected, Geese in the plumage of birds of the year (having, as already 

 stated, the quills and most or all of the tail-feathers of their first plumage) 

 are not capable of breeding, and they do not pass through their second 

 autumn moult until a month later than the adults. The second moult, 

 however, does not last three months as the first did, but, like that of adults, 

 it is over in a month. Adults begin to moult before the young can fly, in 

 the high north before the down has disappeared ; the small feathers are 



