ORGANS OF BREATHING. 
65 
strikes the surface of the water is sufficient to stun a 
bird not prepared for such a blow, or force the water 
up the nostrils. But the Gannet has nothing to fear 
from either of these causes, the front of its head being 
covered with a sort of horny mask, which gives it a 
singularly wild appearance ; and it has no nostrils, 
a deficiency amply remedied by the above-mentioned 
reservoirs of air, and capacity for keeping them 
always filled. Some notion may be formed of the 
rapidity of their descent by a curious mode of 
taking them, occasionally practised by the fishermen 
in the North. A board is turned adrift, on which a 
dead fish is fastened. On seeing it, the Gannet 
pounces down, and is frequently killed or stunned 
by striking the board, or is secured by its sharp- 
pointed beak being actually driven into the wood 
like a nail, and holding it fast. 
There is another bird even more copiously sup- 
plied with air than the above, called the Chavana 
Fidele, in which the skin is entirely separated from 
the flesh, and filled with an infinity of small air- 
cells, the legs and even toes partaking of the same 
singularity, so that it appears much larger than it 
really is, and when pressed by the finger, the skin 
sinks in, but resists pressure like a foot-ball, or other 
elastic body. The air, in this case, is supposed to 
assist in producing a powerful screaming voice, the 
bird being a wader, and not calculated for lengthened 
flights. 
Generally speaking, the bones of birds, excepting 
when young, are without marrow, the gradual absorp- 
tion of which, till the bone becomes a hollow tube, 
is most easily perceptible in young tame Geese, when 
VOL. i. f 
