384 ON THE BIRDS 



an additional protection, by confounding them with the 

 snowy covering of the earth, which prevents their being ea- 

 sily descried by rapacious birds or quadrupeds. 



II. Tetrao. whose geographical range is limited to the more 

 temperate climates, being still protected by feathers as far down 

 as the toes. 



III. Bonasia. a new division for which we propose Tetrao 

 Bonema, L. as the type. In these, the upper portion only of 

 the tarsus is feathered. They occasionally descend to still 

 more southern countries, frequenting wooded plains, as well 

 as mountainous districts, to which latter the true Grouse give 

 the preference. The entire genus is however, properly, bo- 

 real, and is found exclusively in North America, Europe, and 

 Northern Asia. The long and sharp winged Grouse, which 

 replace them in the arid wastes of Africa and Asia, one being 

 met with also in the southern extremity of Europe, we con- 

 sider, in common with all modern authors, as a totally distinct 

 genus. This small group, composed of a limited number of 

 species, inhabits wild regions, remote from man and cultiva- 

 tion, preferring burning deserts to the shelter of the woods. 

 Wandering near the confines of these oceans of sand, so terrific 

 to the eye and the imagination of the human traveller, they 

 boldly undertake to cross them in numerous bands, in search 

 of the fluid so indispensable to life, there found only in few 

 and distant spots. Over the intervening space they pass at a 

 great elevation, and with extreme rapidity, being the only 

 birds of their order that are furnished with wings of the form 

 required for such flights. 



The Grouse, on the contrary, inhabit forests, especially such 

 as are dense, and situated in mountainous districts ; the Bona- 

 six however, as well as the American Pinnated Grous and 

 Cock of the Plains, frequenting level countries, where grow 

 shrubby trees of various kinds. The Arctic Lagopodes are 

 also found on the lofty mountains of Central Europe, where 

 the great elevation affords a temperature corresponding to that 

 of more northern latitudes. There they always keep among 



