CONNECTING AND MISSING LINKS IN THE 



ASCENT TO MAN 



By Richard Swann Lull 



Professor oj Palaeontology, Yale University 



Two truths impress themselves strongly upon the mind of 

 the student of animals, first, the continuity of life, and sec- 

 ond, the immensity of time during which that continuity has 

 endured. Our conviction of the continuity of life is justified 

 by an overwhelming host of facts, obtained in part from 

 observation of existing creatures, in part from the study of 

 the geologic record. The evidence of the continuous suc- 

 cession of living forms is conclusive to modern scientists, 

 having in mind, as they do, the classic experiments of Spal- 

 lanzani, Redi, Tyndal, and Pasteur, which proved, apparently 

 beyond the possibility of dispute, that all life is derived from 

 preexisting life. The evidence afforded by the fossil record, 

 on the other hand, does not at first sight seem so convincing, 

 for the absence of certain 'missing links" in the chain of 

 life is striking. Were the tale a short one, the apparent gaps 

 in the record would be of greater relative moment, but, in 

 view of the great length of the revealed story they become 

 comparatively insignificant. 



These gaps are in reality comparable to missing pages in 

 an ancient and partly mutilated volume, which, although 

 their absence surely mars the perfection of the whole, it 

 nevertheless cannot destroy our understanding of the story 

 that is told if we possess the imagination of die historian or 



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