MAN AN ANIMAL 7 



whether it breathe the sunless ooze of the sea 

 floor or the ethereal blue of the sky. Animals 

 inhale oxygen because they eat carbon and 

 hydrogen. The energy of all animals is produced 

 mainly by the union of oxygen with the elements 

 of carbon and hydrogen in the tissues of animal 

 bodies, the plentiful and ardent oxygen being the 

 most available supporter of the combustion of 

 these two elements. 



Man is, then, an animal, more highly evolved 

 than the most of his fellow-beings, but positively 

 of the same clay, and of the same fundamental 

 make-up, with the same eagerness to exceed and 

 the same destiny, as his less pompous kindred 

 \ who float and frolic and pass away in the seas and 

 V atmospheres, and creep over the land-patches of a 

 common clod. 



II. Man a Vertebrate. 



Man is a vertebrate animal.* He has (anatomi- 

 cally at least) a backbone. He belongs to that 

 substantial class of organisms possessing an 

 articulating internal skeleton — the family of the 

 fishes, amphibians, reptiles, birds, and mammals. 

 Most animals have some sort of skeleton, some 

 sort of calcareous contrivance, whose business it 

 is to give form and protection to the softer parts 

 of the organism. Some animals, as the star- 

 fishes, have plates of lime scattered throughout 

 the surface parts of the body ; others, as the corals 



♦ See ' Classes of Animals,' p. 330. 



