Page:The Zoologist, 4th series, vol 6 (1902).djvu/403

From Wikisource
Jump to navigation Jump to search
This page has been proofread, but needs to be validated.
ANSER GAMBELI AS A BRITISH BIRD.
343

characterises the first plumage. In this bird the under parts have become a dirty-looking umber; on the upper part of the breast there are a few feathers left marbled with blackish umber, these alone showing clearly enough that it is a case of the extraction of the dark colouring matter. The upper breast is drab, with the edges of the feathers worn and abraded-looking. The flanks have a few of the dark large new feathers coming, bordered with dull white. The general appearance of the upper parts is paler than in first plumage, the bill is clearer, and the nail nearly all white. Bill 2·13 in.; tarsus 2·65 in.; wing 15½ in.

In the third stage the under parts have now assumed that appearance which the Americans call "speckle belly," the dark markings having so far faded away that the centres only of the feathers remain dark, making the under parts look as though speckled all over with dark umber. It is not necessary to describe any other portions of this bird's plumage, excepting that there is scarcely a trace of white at the base of the bill, and the blackish has a rusty look.

Male.—Length 28¾ in.; wing 16 in.; weight 5½ lb.; bill 2·13 in.; tarsus 2·93 in. The nail on bill is entirely dark.

The fourth stage is very interesting; it is still a "speckle-belly," but the clean-looking new greyish drab feathers are appearing on the upper breast and amongst the under parts, which are becoming almost white, while some of the old feathers have almost entirely lost the dark centres, giving a much whiter appearance to the under parts, which makes the speckles show up more distinctly. The flank feathers are well grown, and have broad white outer margins. The upper tail-coverts have become almost entirely white. There is a good space of white at the base of the bill, which is clearer yellow with the nail partly white. In the wing this bird shows the paler slaty drab outer wing-coverts, which runs through the rest of the series, becoming palest in the black-breasted adults, and in this differing distinctly from the adults of A. albifrons.

Male.—Length 28½ in.; wing 16½ in.; weight 5¼ lb.; bill 2·1 in.; tarsus 2·95 in.; neck 8¾ in.