THE GREBES. 203 
they cannot walk, but creep, so to speak ; for they must hold them- 
selves nearly upright, supported on the croup, the toes and the tarsi 
being extended laterally. But ungraceful as they are on shore, so 
much greater is their elegance on the water. They are covered with 
a close warm down, so close and so lustrous that muffs are made 
from their breast. 
M. Noury, director of the Museum of Natural History at Elbceuf, 
who has carefully studied the habits of the Grebes, relates of the 
Great Crested Grebe, that its nest is a perfect raft, which floats upon 
Fig. 80.—Auk. 
the surtace of our ponds and lakes. It is a mass of thick stems of 
aquatic herbs closely woven together ; and as these materials contain 
a considerable quantity of air in their numerous cells, and various 
gases being engendered in decomposition, these aériform supporters 
render the nest lighter than the water. In this improvised ship, and 
upon this humid bed, the female Grebe silently sits and hatches her 
progeny. But if anything unforeseen disturbs her security, this wild 
bird plunges one foot into the water, which she employs as an oar 
to transport her dwelling from the threatened danger. 
Grebes are inhabitants of the old and new Continents.! Among 
the European species may be noticed the Crested Grebe (Podiceps 
