KANGAROOS. 469 



known to snap the bone asunder when startled into taking a 

 sudden spring, so powerful is their contractile force. 



The extraordinary capability they have of leaping, especially the 

 small pretty little hare kangaroos {M. Leporoides), so called from 

 their being about the same size as the common hare, can be judged 

 by the following account which is given by Mr. Gould of a per- 

 formance he once witnessed. " While out on the plains of South 

 Australia," he writes, " I started a hare kangaroo before two fleet 

 dogs ; after running to the distance of a quarter of a mile it 

 suddenly doubled and came back upon me, the dogs following 

 close at its heels. I stood perfectly still, and the animal had 

 arrived within twenty feet before it observed me, when to niy 

 astonishment, instead of branching off to the right or the left, it 

 bounded clear over my head, and on descending to the ground 1 

 was enabled to make a successful shot by which it was procured." 



As Professor Owen pointed out many years ago, there un- 

 doubtedly exists with very few exceptions a wonderful harmony 

 between the climate and the structure and habits of the animals 

 to be found diffused over the world's surface. Thus in countries 

 subject to prolonged droughts, such as the plains of South 

 Africa and Australasia, rapidity of locomotion is of vital necessity 

 to those animals that require succulent food or cannot exist 

 without water, for the distance to be travelled before these re- 

 quirements can be found is often so great that a slow-paced 

 animal would die on the road. In all hoofed, and in fact in the 

 majority of all quadrupeds, the whole four hmbs are therefore 

 exclusively used for locomotion, but in the case of the kangaroo 

 we have an animal which only employs the hind-limbs for this 

 purpose, the front pair being used as required, as prehensile 

 organs, or for the requisite manipulation of the pouch which 

 its peculiar uses render necessary. Accordingly the hind-limbs 

 are constructed to serve the purpose of the whole four in other 

 animals, and to carry the kangaroo with great speed long dis- 

 tances over the drought-dried plains, which it has occasionally 

 to traverse in pursuit of the absolutely requisite water. 



The hair of a kangaroo is at first only a short, ashy-coloured 

 down, biTt subsequently, though after an unusually long period as 



