jg THE ANIMAL KINGDOM. 



The following four pictures will be of great use to you, 

 for you will of course see that the horse has a back-bone 

 (vertebra), and this will remind you that all animals having 

 back-bones are called Vertebrated ; and when you look 

 at the Crab (Fig. 2), you will remember that it is covered 

 with a hard crust which, indeed, represents its skeleton 



Fig. i. 



Example of Vertebrated or Back-boned Animals/ 



THE HORSE. 



growing outside, instead of inside, as in Vcrtebrata. The 

 different portions of this external skeleton are jointed into 

 each other, and, therefore, the whole of this division is 

 called Articulated, which is derived from a Latin word 

 meaning jointed. 



This external skeleton is not always the hard casing in 

 which the Lobster or Crab is contained : it is sometimes 



