74 THE FLIGHT OF BIRDS 



character of the different muscles. Remarkable also 

 is the large size of the Chicken's Elevator muscle. 

 Its wild kinsman, haunting the jungle as it does, has 

 to rise to its perch without any wind to help it, so 

 that all the work of raising the wing must fall upon 

 the muscle. But the effort required is not a pro- 

 longed one, and so the muscle is pale. In the 

 Sparrow-Hawk and, I believe, in other birds of prey, 

 the Elevator is very small. Since they usually start 

 to fly from a perch at some height above the ground, 

 there is no difficulty in getting up speed enough to 

 make the office of the Elevator largely a sinecure. 



The brown flesh on a Chicken's leg, though the 

 human palate pronounces it inferior, is, nevertheless, 

 when regarded as muscle, of distinctly better quality. 

 The Fowl is primarily a runner, not a flyer ; hence, 

 presumably, the darker colour and the greater 

 strength and endurance of the leg muscles. More- 

 over, these muscles are kept on the strain throughout 

 the night; by the bending of the knee and ankle 

 joints the machinery of muscles and tendons through- 

 out the leg is set to work and the bird's toes strongly 

 grip the perch. His weight keeps the legs bent, and 

 the bending of the legs keeps muscles and tendons 

 to their work. Were they to relax for a moment the 

 bird would probably lose his life ; he would fall to the 

 ground and some hungry carnivore, that happened 

 to be prowling about, would seize him. But though 

 in the Fowl the leg muscles are darker in colour than 

 those of the breast and wings, they are not in section 

 ridged and granulated like the great Pectoral of 

 birds that are strong flyers. In the Moorhen, I have 

 noted that the leg muscles are rather more ridged 



