THE LIVING WORLD. 
369 
vided with eighteen feathers on either side of the neck, of black and brown, 
which are distensible, but which generally lie close except during the time of 
courtship. He has also a small crest and a semi-circular comb of orange-col¬ 
ored skin over each eye. The sacculated appendages on the neck are used to 
produce a drumming noise, or are certainly in some way instrumental in the 
production of the booming sound which they utter during the strutting season. 
Naturalists, however, are not united in their opinions respecting the means 
employed to produce the sound. It has been observed that the pinnated grouse 
inflates the sacs on his neck, and at the instant of their collapse, by a violent 
expulsion of the air within, a booming noise is heard. But the same sound, 
though not so loud, is produced by the turkey-gobbler, cock-pheasant, and by 
other species of prairie-grouse, though none of these are provided with the air 
sacs. The ques- 
tion, therefore, 
of just how the 
noise is pro¬ 
duced remains 
unsettled. 
The Hazel 
Hen (Te tras 
bo nasi a} is a 
large species of 
grouse, resem¬ 
bling the sage 
hen in habits, 
but found only 
in Europe. The 
body markings 
are considerably 
darker than 
those of our 
prairie chickens, 
and it is some¬ 
what larger. 
The head is dis¬ 
tinguished for 
having a bold crest of feathers, which are balanced, so to speak, by a thick 
growth of feathers under the throat giving to it a bearded appearance. From 
base of the bill runs a crescent of white over to the neck and to the breast, 
while another strip of white crosses on a line with the eyes, which impart a 
very pleasing appearance to the bird. While found chiefly upon open ground 
it not infrequently resorts to the brush to prey upon insects that are to be 
found about rotting wood. 
The Black Grouse (Tetras tetrix) is also a north Europe species, dis¬ 
tinguished, as the name implies, for its black feathers which are nowhere re¬ 
lieved except on the inner edges of the wing, which are white. The tail, how¬ 
ever, is its glory, being composed of large feathers which curve gracefully from 
the ’centre outwardly. The head is also decorated with a small crest of 
feathers. 
24 
PRAIRIB HEN AND HER BROOD. 
