TETRAO. 423 
Genus TETRAO *: 
The genus Tetrao was included by Linnzus in 1766 in the twelfth 
edition of his ‘Systema Nature’ (i. p. 273). The Capercaillie has by 
common consent been regarded as the type. 
The Grouse may be distinguished by their feathered tarsi and the 
absence of spurs. The wings are short, rounded, and very convex, and 
the nostrils are covered with short feathers. 
This genus contains about twenty species, which are confined to the 
Palearctic and Nearctic Regions. Six species are European, of which 
four are British. 
The birds in this genus frequent mountains, moors, and forests. They 
are more or less gregarious in autumn and winter. They run and walk 
on the ground, and several of the species perch freely in trees; their 
flight is swift, and performed with rapid beatings of the wings, and when 
they rise they make a whirring sound. Their notes are harsh. Their 
food consists of insects, fruits, berries, seeds, grain, tender shoots, and 
buds. Some of the species are monogamous, others polygamous. Their 
nests are slight, placed under the shelter of small bushes or amongst 
heath, and their eggs are numerous. 
* Brisson in 1760 divided the genus Tetrao of the first edition of the ‘Systema Naturee’ 
of Linnzus into two genera, Lagopus and Perdix; but in 1766 Linneus reunited them in 
his twelfth edition under the old name. The genus Lagopus, of which the Willow-Grouse 
is the type, can only be considered additional to that of Linnzeus by making some other 
bird the type of the Linnean genus. The first ornithologist who subdivided the Linnean 
genus Tetrao was probably Latham, who in 1787 (Gen. Syn. Suppl. i. p. 290) adopted 
Brisson’s genus Perdix for the Partridges. The Ptarmigan appear to have been first 
elevated to the rank of a genus by Leach in 1816 (Syst. Cat. Mamm. &c. Brit. Mus. p. 27), 
who adopted Brisson’s genus Lagopus for them. As the Black Grouse is the only Tetrao 
mentioned by Leach, it might be argued that he assigned this bird as the type; but as 
there seems to be some doubt on the question, I prefer to regard the Wood-Grouse as 
such, because it has been so considered by the majority of writers. Under these cireum- 
stances the genus Lagopus of Brisson becomes additional to the genus Tetrao of Linnzeus ; 
and the Willow-Grouse, his Zagopus lagopus, must be regarded as the type if this genus 
be recognized. 
