GIANT BIRDS. 149 



namely, the little Kiwis of New Zealand, which, although 

 by no means entitled to rank as Giant Birds in the 

 proper sense of that term, yet as being closely related 

 to the typical members of that group, must find a place 

 therein. Before, however, we can consider the fossil 

 members of this group, it is necessary that we should 

 have some idea of the general structure of the leg of a 

 bird, since it is this part of the skeleton which is most 

 commonly met with in a fossil condition, and which 

 affords the most important clue as to the size and 

 affinities of the bird to which it belonged. Some 

 observations on this point have already been made in 

 the chapter on Giant Eeptiles; but since those were 

 mainly directed to showing the resemblance between 

 the leg of a bird and that of a reptile, they are not well 

 suited to our present purpose. 



A bird's leg, then, as shown in Fig. -'6, B, is com- 

 posed of four segments ; the upper, short one corre- 

 sponding to the human thigh-bone, and the lowest 

 representing the toes, which are composed of several 

 small bones. Between these two segments are the two 

 long and slender bones shown in the figure. The upper 

 and longer of these two (Fig. 47, A) corresponds with 

 the human leg-bone, plus the huckle-bone welded on 

 to its lower end. The lower and shorter bone, of which 

 another example is shown in Fig. 47, B, is a very 

 remarkable bone indeed, and may be conveniently 

 called the cannon-bone. It is really composed of three 

 separate long bones, of which the ends remain free at 

 the lower extremity and carry the toes, and also of the 



