OUR FACE FROM FISH TO MAN 



48-53) set forth a few of the facts which have 



convinced modern anatomists that man, Hke other 



mammals, was not created at one stroke, but that 



he reached his present condition by gradual stages 



of modification, which, thanks to the unremitting 



labors of many palaeontologists and anatomists, 



now appear to be fairly well understood. None of 



these stages is hypothetical ; they are either known 



fossil forms or are the surviving and little-modified 



descendants of known fossil forms. 



From the imperfect nature of the fossil record 



we can never expect to recover the infinite number 



of links in the direct line of ancestry of man or of 



any other mammal. The record affords us only 



successive structural stages that are more or less 



nearly related to the main line of ascent from fish 



to man. 



The story told in these illustrations has not been 



invented by the writer. It has slowly revealed 



itself as the palaeontologists and anatomists of a 



century past have gradually unearthed it. During 



the past fifteen years great progress has been made 



all along the line of stages I to X, either in the 



discovery of hitherto unknown or little-known 



forms, or in the determination of the sutural 



84 



