Animals Before Man 



and labyrinthodonts emphasize a feature of 

 the animals of the ancient world, that neither 

 the individual species nor the groups of which 

 they formed part were so sharply distinguished 

 from one another as are those of the present 

 time. Life, from its beginnings, progressed 

 along divergent lines, and as we go backward 

 in time we find these lines approaching one an- 

 other and come upon animals combining char- 

 acters now found in two or more orders. It is 

 the dying out of these intermediate forms, or 

 their transformation into others, that enables 

 us to divide living animals into well-marked 

 divisions. 



The great marine reptiles, the Ichthyo- 

 saurs, or fish lizards, that were so common in 

 the seas that washed the coast of ancient Eu- 

 rope, seem to have been but scantily repre- 

 sented in this hemisphere. In the days when 

 the earth was overrun by reptiles these crea- 

 tures occupied the place now held by whales 

 and dolphins, a place for which they were ad- 

 mirably adapted ; for while such water-loving 

 animals as crocodiles and turtles do occasion- 



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