II 



THE EARLIEST KNOWN VERTEBRATES 



"We are the ancients of the earth 

 And in the morning of the times." 



There is a universal, and perfectly natural, de- 

 sire for information, which in ourselves we term 

 thirst for knowledge and in others call curiosity, 

 that makes mankind desire to know how every- 

 thing began and causes much speculation as to 

 how it all will end. This may take the form 

 of a wish to know how a millionaire made his 

 first ten cents, or it may lead to the questions 

 What is the oldest animal ? or, What is the 

 first known member of the great group of back- 

 boned animals at whose head man has placed 

 himself? and, What did this, our primeval and 

 many-times-removed ancestor, look like ? The 

 question is one that has ever been full of inter- 

 est for naturalists, and Nature has been inter- 

 rogated in various ways in the hope that she 



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