VARIETIES OF PLUMAGE. 55 



regularly summer and winter in the country, and are gene- 

 rally distributed over it. 



DOMESTICATION AND CHANGE OF PLUMAGE. 



Tf we leave out of the question the wood grous, which, as 

 a British bird, is extinct, and the quail, which is both rare 

 and local, we have, in our native gallinae, a regular suc- 

 cession of inhabitants, from the highest mountain top to the 

 close vicinity of the most warm and sheltered dwelling, all 

 mingling a little with each other on the confines, but still 

 each preserving its locality, while the character of that 

 locality remains unchanged, more decidedly perhaps than any 

 other birds. All birds straggle a little at times ; but still 

 it is rare to find ptarmigan anywhere but on the mountain, 

 grous anywhere but on the moor, black grous but in the wild 

 dell, or partridges but on or near the cultivated field. Thus 

 we know where to find any of these birds at all seasons j and, 

 according as we ourselves are situated, we can study their 

 habits with much certainty. 



We find the ptarmigan on the height, changing by nature 

 with the seasons, and braving the very excess of the winter. 

 In the grous we have a bird in the dry cover of the heath, 

 which affords it shade and protection in the summer, and 

 shelter in the winter, while the short but firm stems support 

 the covering of its snow house, which, in many instances, 

 remains unmelted for half the year ; the tops of the same 

 heath, and the mosses and lichens which are growing under 

 it, despite the snow, serving the birds for food during the 

 time of their confinement. The heath thus serves to equalize 

 the temperature of the seasons to the grous, in the same way 

 that the transition from house to tent, and from tent to 

 house, equalizes them for the rude inhabitants of high lati- 

 tudes; and thus, the change in the colour of the plumage not 

 being necessary, that does not take place. 



