NATATORES. PODICEPS. 391 
in the form of their feet, were arranged with the Coots and 
Phalaropes (birds also belonging to different families), and 
formed a truly artificial division, under the title of Pinnati- 
pedes. Instead of the free tibia, and the gressorial foot, cal- 
culated for progress upon land, and at the same time fur- 
nished with distinct membranes to assist in swimming, as we 
see exemplified in the Coot, the feet of the Grebes are 
formed upon a very different plan, and expressly adapted 
for the watery element, as the position of the tarsus and the 
articulation of the toes are such as to give no stability to the 
body upon land, and progression there is effectually prevent- 
ed by the restrained action of the tibia. Except in the toes 
being separated towards their extremities, and each furnished 
with a distinct web, the form of the legs and feet approaches 
closely to that seen in the genus Colymbus ; the tarsus suffer- 
ing an equal lateral compression, and the outer toe exceeding 
the other two in length. The Grebes are remarkably active 
in the water, which they never quit, as they even breed there ; 
making their nests amidst the reeds and other strong aquatic 
herbage that is found im the localities they inhabit. From 
their shortness of wing, and want of tail, they rise with dif- 
ficulty, and scarcely ever have recourse to flight, except for 
change of abode, or migration; as, when pursued, they al- 
ways endeavour to escape by diving. They feed on fish, 
aquatic insects, and vegetables. The genus has a wide geo- 
graphical distribution, some species being found in every 
quarter of the globe. 
