88 THE TALLEST MAMMAL. 



To every rule there is, however, an exception, and there 

 are a few groups of living large mammals whose existing 

 members appear never to have been surpassed in size by 

 their fossil relatives. Foremost among these are the 

 whales, which, as we have seen in a previous chapter, now 

 appear to include the largest members of the order which 

 have ever existed. The so-called white, or square-mouthed, 

 rhinoceros of South Africa seems also to be fully equal in 

 size to any of its extinct ancestors ; and the same is 

 certainly true of the giraffe, which may even exceed all its 

 predecessors in this respect. Whether, however, the fossil 

 giraffes, of which more anon, were or were not the equals 

 in height of the largest individuals of the living species, 

 there is no question but that the latter is by far the tallest 

 of all living mammals, and that it was only rivalled in this 

 respect among extinct forms by its aforesaid ancestors. 

 Moreover, if we exclude creatures like some of the gigantic 

 dinosaurian reptiles of the Secondary epoch, which, so to 

 speak, gained an unfair advantage as regards height by 

 sitting up on their hind legs in a kangaroo-like manner, 

 and limit our comparison to such as walk on all four feet 

 in the good old-fashioned way, we shall find that giraffes 

 nre not only the tallest mammals, but likewise the tallest 

 of all animals that have ever existed. 



In the great majority of animals that have managed to 

 exceed all their kin in height, the increment in stature has 

 been arrived at by lengthening the hind limbs alone, and 

 thus making them the sole or chief support of the body. 

 In some of these cases, as among the living kangaroos 

 and the extinct dinosaurs, the body was raised into a more 

 or less nearly vertical position, and the required height 

 attained without any marked elongation of the neck. In 

 birds, on the other hand, like the ostrich, the body is 

 carried in nearly the same horizontal position as in a 

 quadruped, but both the hind legs and the neck have been 

 elongated. The giraffe, however, has attained its towering 

 stature without any such important departure from the 

 general structure characterizing its nearest allies, and thus 

 preserves all the essential features of an ordinary quad- 

 ruped. Belonging, as we have had occasion to mention 



