TETRAO. 
77 
merly all included under that title, but have, by 
modem ornithologists, been sub-divided, both on 
account of a difference of habit, and a modifi- 
cation in the form of several of the parts, and 
Tetrao is now kept for those large and power- 
ful species, with expanded tails and naked feet, 
which are polygamous, and dwell in shaded 
forests or wooded districts. Once we possessed 
a truly typical species, for the recovery of which 
great exertions are making; but the true forms are 
now chiefly found in Northern Europe and Ame- 
rica, though a very near example of the general 
shape and appearance may be seen in the female 
of our black cock, the greatly developed tail of the 
male presenting a variation, which has been con- 
sidered by some as of sub-generic importance. 
Tetrao of modern ornithologists. — Generic cha- 
racters . — Bill short, very strong and arched 
from the base; nostrils basal, lateral, and 
hidden from view by closely set feathers ; a 
naked skin above the eyes, enlarging in spring, 
and coloured brightly ; wings short, concave, 
third and fourth quills longest; tail very ample 
and expanding, (rounded*;) feet naked, with 
the edges of the toes fringed ; tarsi feathered. 
Types, T. urogallus, obscurus. Europe, Northern 
Asia, North America. 
* If Lyrurus be kept as a sub-genus, “ rounded” should be 
Inserted in the characters. 
