eh a 
TETRAONID A. 343 
Famiry TETRAONIDA. Partridges and Grouse. 
Bill and tail very short. Hallux elevated. 
CrypTronyx, Tem. Bill short, thick ; the mandibles of 
equal length. Nostrils placed in the middle of the 
bill, and covered by a long naked membrane. Feet 
large. The hinder toe elevated, and without a claw. 
Head conspicuously crested. 
i C. coronatus. Mus. Carl. pl. 64. 
OpontorHorus, Vieil. Bill naked at the base, con- 
vex above, much compressed, and with a double tooth | 
near the point. Orbits and lores naked.* 
Tocro of Buffon. 
Orrveis, Ill. Bill moderate, slender, straight. Nos- 
trils lateral, linear, placed near the middle of the bill. 
Feet three-toed, slender. Hind toe wanting. Wings 
and tail very short ; the latter nearly concealed. 
a O. nivosus. Zool. Ill. i. pl. 163. 
Terrao. Grouse. Bill short, very thick. Tarsus fea- 
thered. Four-toed. Eyebrows naked. Tail moderate, 
of twelve feathers. Wings short. 
Tetrao, Linn. The tarsus feathered, but the toes naked. 
Sides of the neck, in the male, often with cenenee 
feathers. Tail even. Eyebrows plumed. 
T. Scoticus. Selby, pl. 59. f. 1. urogallus. P. Enl. 73. 
Lagopus, Willughby. Bull with the base thickly fea- 
thered. Eyebrows naked and smooth. Tarsus and toes 
thickly covered with feathers. 
L. mutus. Selby, pl. 59. f. 2. 
Lyrurus, Sw. Toes naked. Tail lyre-shaped. 
L. tetrix. Selby, pl. 58. 
Pterocles, Tem. Sand Grouse. Toes naked. Bill 
slender ; the base thickly covered with feathers. ‘The 
hind toe very short, or entirely wanting. Wings long, 
pointed. Tail graduated or cuneated. 
P. arenarius. Pl. Col. 52. paradoxus. Pl. Col. 95.+ 
* I have not been able to examine accurately these first two genera. 
+ 1 consider this bird as the real type of the whole group. 
zZ 4 
