180 ANIMAL SKETCHES. CHAP. 



stand alone in some at least of his peculiarities. He 

 belongs to a group of birds, all of them unconventional in 

 form, all of them incapable of flight, all of them powerful 

 in leg and thigh, called the struthious birds, or sometimes, 

 from the raft-like shape of the breast-bone, the ratite 

 birds. If you have ever picked the breast of a fowl or a 

 pigeon, you must have noticed that the breast-bone has 

 what is called a keel, a plate of bone coming down in the 

 middle and dividing the breast into two halves. From the 

 possession of this keel (Lat. carina) the ordinary conven- 

 tional birds the songsters, gulls, climbers, waders, fowls, 

 birds of prey, and the rest are called carinate birds. The 

 struthious birds, however, have no keel to the breast- 

 bone. And since it is to this keel that the great wing 

 muscles, through which flight is rendered possible, are 

 attached, one can quite understand why the struthious 

 birds those unconventional walkers and runners who 

 despise the use of wings should have this keel 

 undeveloped. 



You may generally see at the Zoo not only the ostrich, 

 but the other members of his clan, the rhea, the cassowaries, 

 the emus, and the strange little New Zealand kiwi. 

 Perhaps you might expect that the members of this small 

 and peculiar clan of birds would all be found in the same 

 part of the earth's surface. But that is not so. They are 

 widely scattered, though the Australian region has by far 

 the greater number of species, and each region of the 

 world which they inhabit has its own special member of 

 the group. Africa has the two-toed ostrich, which also 

 ranged to India in pre-historic times ; South America has 

 the rhea or three-toed ostrich, smaller and more sober- 

 hued than his African cousin ; the emus are Australian ; 

 the apparently wingless kiwis are from New Zealand ; and 

 the cassowaries where, think you, do they come from ? 

 No, pardon me, they do not come from North Africa, 



