170 NEW ZEALAND NATURE-STUDY BOOK 
gravity, and nearer the head than this region. The legs 
are fixed immediately below the centre of gravity, and 
hence in the best possible position to support the animal’s 
weight. At the end of each foot are four toes, one of 
which is directed backwards ; each toe ends in a single 
claw.. The body is protected by a covering of overlapping 
feathers. Each feather has a free end and a fixed end, the 
former pointing towards the tail. The feathers, moreover, 
are light, warm, and smooth, and furnish the best of all 
coverings for animals adapted for flight. The legs are 
feathered to the end of the second joint, and the feet are 
covered with scales. The wings and tail bear a number of 
large feathers, which are used by the bird when flying. 
The Head. The head is small and tapering, and ends 
in a sharp, arched, and horny bill, the upper mandible of’ 
which projects beyond the lower one. The eyes are large 
and round and placed at the side, so that the animal is 
obliged to turn its head in a curious way when looking at 
an object on the ground. The eye is closed by an upper 
and lower eyelid. There are no external ears, but a little 
below each eye a small opening occurs leading to the 
internal ear. 
The Wing. Each wing consists of three main seg- 
ments, (a) the upper arm; (b) the lower arm ; (c) the wrist 
and hand---the latter bearing three digits seen when the 
feathers are removed. (See fig. 110) 
When at rest these segments can be folded up and made 
to lie close to the body. The large quill feathers are fixed 
to the fore-arm ‘and wrist and hand, and the wing is con- 
trolled by powerful muscles attached to the keel of the 
breast-bone, 
Hind Limbs and Feet. The hind limbs or legs are 
formed to support the entire weight of the body except 
during flight, and are for this reason very strong. The 
