- (11) 
Every one knows the varied industry which Birds exercise in 
the construction of their nests, and the tender care which they 
take of their eggs and their young ones; il is the principal part of 
their instinct. Their rapid passage through the different regions 
of the atmosphere, and the Hvely and constant action of this 
element upon them, afford the means of presaging variations of 
the atmosphere of which we have no idea; which circumstance has, 
from the earHest times, induced superstition to attribute to Birds 
the power of announcing the future; (i) neither do they want 
memory, or even imagination, for they dream; and every one 
knows with what facility they are tamed, allow themselves to be 
trained to different services, and retain airs and words. 
Division of the Class of Birds into Orders, 
Of all the Classes of Animals that of Birds is the most marked, 
that in which species most resemble each other, and which is 
separated from all others by the greatest interval ; its subdivision 
is consequently more difficult. 
Their distribution is founded, like that of Mammalia, on the 
organs of manducation, or the beak; and on those of prehension, 
that is to say, the beak, and, especially, the feet. 
We are first struck with the palmated feet, or those of which 
the toes are united by membranes, which distinguish all the 
swimming birds. The backward position of these feet, the length 
of the sternum, the neck often longer than the legs (to reach the 
deeper places) , the close smooth plumage (impervious to water), 
contribute to make the Palmipedes good navigators. 
In the other Birds which have, generally, some little web, at 
least between the external toes, we observe elevated tarsi ; thighs 
naked of feathers towards the lower part ; a slender shape ; in a 
word, all the construction proper for fording or walking along 
the edges of waters, to search for food. Such in fact is ihe diet 
of the greater number, and, although some live on dry land, they 
are called Shore Birds or Grallae. 
ment when the bird is ready to be hatched, that this humour disap- 
pears, entering by the naval into the belly of the young bird. The 
yolk is supposed to be absorbed in the interior of the body, as it passes 
into the intestines, and may be considered as a sort of milk or first 
nourishment. 
(1) The Palmipedes and Grallae, for instance, always come to land 
when they foresee a storm ; the Procellariae, more especially, amongst 
the former, and the Fulicse amongst the latter. 
