THE ANIMAL KINGDOM. 



175 



43. To what sub-kingdom, class, and order do the Seal 

 and the Porpoise respectively belong ; and what are the 

 most striking differences presented by these animals ? . 



44. How are Fishes distinguished amongst vertebrate 

 animals ? 



45. What characters distinguish birds from Mammals 

 on the one hand, and Reptiles on the other ? 



46. What are the chief differences between the Apes of 

 the old world and those of the new world ? 



47. What are the characters of the order Rodentia? 

 Give examples of that order. 



48. What are the Infusoria ? Give an account of the 

 structure and habits of any member of this group. 



49. To what sub-kingdom, class, and order do Elephants 

 belong ? How many species of Elephants are there, and 

 where are they found ? 



50. What are the most striking peculiarities of Planti- 

 grade animals ? 



