194 
TETRAO OBSCURUS. 
the Tetrao rupestris , which we do not consider well 
established, any more than the new species of Mr 
Brehm. The species of Lagopus , as might be inferred 
from their inhabiting' high northern latitudes, are 
common to both continents, with the exception of the 
red grouse, T. scoticus , which is peculiar to the British 
islands, and which, from its not changing the colours 
of its plumage with the seasons, may be considered as 
forming the passage to the true Tetraones. Of these, 
there are live in North America, each and all distinct 
from the three European. Of the two Bonasice , one is 
peculiar to the old, and the other to the new continent, 
the former having sixteen, the latter eighteen feathers 
to the tail. Thus the entire number is seven in Europe, 
while it is eight in North America. Setting aside the 
two common to both, and the respective Bonasice^ we 
may consider the cock of the woods of Europe as the 
parallel of the cock of the plains of America. The 
black grouse, T. tetrix , will find its equivalent in the 
dusky grouse, T. obscurus; but the T. hybridus has 
no representative in America, any more than the T. 
scoticus. These, however, are more than replaced as 
to number, by the T. phasianellus , T. cupido , and T. 
canadensis , all American species, which have none 
corresponding to them in the old world. 
Perhaps no other naturalist has personally inspected 
all the known species of this genus of both continents, 
and having examined numerous specimens even of some 
of the rarest, and possessing all but one in my own 
collection, my advantages are peculiar for giving a 
monography of this interesting genus. Such a work it 
is my intention hereafter to publish, illustrated with 
the best figures, and accompanied with farther details 
respecting their habits. In the mean time, I shall merely 
state, that, being replaced in Africa by Pterocles , and 
in South America by Tinamus , all the known species of 
grouse are found in North America, or in Europe, the 
European also inhabiting Asia ; from whose elevated 
central and northern regions, yet unexplored, may be 
