36o THE NESTS AND EGGS OF BRITISH BIRDS. 



Range of egg colouration and measurement : 

 The eggs of the CapercailHe are from eight to twelve 

 in number, occasionally fourteen or even sixteen. They 

 vary from brovvnish-bufif to rcddish-bufif in ground 

 colour, blotched sparingly, and spotted and speckled 

 thickly with rich reddish-brown. The markings are 

 generally small, rarely as big as a pea, and are usually 

 distributed pretty evenly over the entire surface of the 

 egg. Average measurement, 2"2 inches in length, by v6 

 inch in breadth. Incubation, performed by the female, 

 lasts twenty-six days. 



Dl\GNOSTIC characters : The size of the eggs, 

 yellowish ground colour, and small distinct spots, dis- 

 tinguish them from those of all other allied species. 

 They most closely resemble those of the Black Grouse, 

 but may be instantly separated by their larger size. 



Family PIIASL\NID^. Genus Tetrao. 



Sub-family TETRAONINM. 



BLACK GROUSE. 



Tetrao tetrix, Linnceus. 



Single Brooded. Laying season, April and May. 



British breeding area: The Black Grouse is not 

 so widely and generally distributed in England as was 

 formerly the cas?, nevertheless it breeds locall}' in all 

 the counties south of the Thames and the Bristol Avon, 

 with the one exception of Kent. It is also locally dis- 

 tributed in Wales, the Midlands, and Norfolk, and also 

 in every county north of Notts up to the Border. It is 

 much more generally dispersed in Scotland, including 

 some of the Inner Hebrides, but does not extend beyond 



