46 DIVERSIONS OF A NATURALIST 



ground. It is numerous at an elevation far above the 

 growth of trees in Norway, and occurs also in the 

 Pyrenees and the Alps. It turns white in winter (as 

 do all the species of Lagopus except the red grouse), 

 and differs in many features of structure from the red 

 grouse and the willow-grouse. It is called " L. 

 mutus." A fourth species of Lagopus is L. rupestris, 

 of North America, Greenland, Iceland, and Siberia. 

 Spitzbergen has a fifth species, L. hemileucurus, a large 

 form. The sixth and smallest species of Lagopus is the 

 L. leucurus of the Rocky Mountains. There are yet 

 further some excellent grouse-like birds, which are 

 separated to form other genera distinct from Lagopus. 

 Though they do not inhabit the British Islands, some 

 of them are brought occasionally to the London market. 

 The hazel-hen of continental Europe is one of these, 

 and is considered to be the most delicate game-bird that 

 comes to table. It is placed in the genus Bonasa, and 

 receives the specific name " sylvestris." The French 

 call it " gelinotte " (under which name various kinds of 

 cold-storage grouse are often served in London clubs and 

 restaurants), the Germans " hasel-huhn," and the Scandi- 

 navians " hjerpe." It is a purely forest bird. It is re- 

 presented in North America by four other species, of 

 which the best known is Bonasa umbellus, called by 

 the Americans the ruffed grouse or birch-partridge. 



Another genus of Tetraonidae, or grouse-birds, is 

 called " Canachites," and contains the species known as the 

 Canadian spruce-partridge, Franklin's spruce-partridge, 

 and the Siberian spruce-partridge. Nearly allied to 

 these is a genus Dendragapus, with three North American 

 species. Then we have the sage-cock of the plains of 

 California (Centrocerus urophasianus), three species of 

 sharp-tailed grouse (genus Pediocaetes), and " the prairie 



