THE BIRDS 281 



The wings are larger than in the cassowary and emu, and, although 

 useless as organs of flight, are used by the bird as sails to add 

 to its speed when running. A full-grown Ostrich often stands 

 eight feet high ; its great length of leg and enormous stride combine 

 to make it the fastest of running creatures. It will quickly out- 

 distance a galloping horse, as with outspread wings it speeds 

 across the plains, covering twenty-five feet or more at a single 

 stride. Indeed, if it were not for its habit of running in a circle, 

 it would be impossible to overtake and capture a running Ostrich. 

 Unlike the emu, the Ostrich is polygamous, each cock bird 

 having five or six mates, for whom he usually does battle at the 

 beginning of the mating season. At other times of the year, flocks 

 of forty or fifty birds are often seen in company, and it has been 

 noticed by travellers that they have a curious liking for the com- 

 panionship of zebras, hartebeests, and other species of antelope. 

 In its wild state the food of the ostrich is strictly of a vegetable 

 nature, and as an aid to digestion it swallows a quantity of grit and 

 large stones, but in captivity this bird will eat almost anything of 

 an animal or vegetable nature, and swallows bones, nails, coins, or 

 any other strange thing it can pick up. Although it will drink 

 freely when a supply of water is at hand, an Ostrich will rarely 

 go out of its way to seek it, and is able to exist for very long 

 periods without drinking at all. 



The Rhea in South America takes the place of the ostrich in 

 the Old World, and is often called the " American Ostrich." The 

 Rheas agree in many ways with the ostriches ; the head, neck and 

 bill are similar, and in both families of birds there is no after-shaft 

 to the feathers. The legs and feet are equally stout and strong, 

 but the Rheas have three toes, instead of two, terminating in strong 

 claws. The largest species is about two feet shorter than the 

 ostriches, and they run with great speed, raising their wings alter- 

 nately above the back, apparently to quicken their pace. Rheas 

 are gregarious in habit, consorting together in flocks of twenty 

 or more, and are frequently seen in company with deer or guanacos. 

 In the breeding season the birds separate, each cock bird going 

 off with several hens, which he jealously guards, attacking with 

 great viciousness any other male bird which attempts to interfere 

 with them. Although such large and striking-looking birds in 

 their natural haunts the treeless flats of the Argentine pampas 



