DARWIN AND PALEONTOLOGY 213 



along the strictest lines of observation, he was 

 less interested in how nature might, should, or 

 would work than in how nature does work. Of 

 his trial hypotheses that of adaptation through 

 selection of minute favorable variations he can- 

 didly tested by all the facts he could bring to- 

 gether; among these, however, were none of the 

 facts observable only in close phyletic series of 

 fossils. This is a fair way to estimate Darwin 

 and to be influenced by him, namely, by his strict 

 inductive methods and in his times, not in ad- 

 vance of his times. 



In the last half century thousands of fossil or- 

 ganisms of aU kinds have been exactly studied 

 and compared, more or less complete descent 

 series of vertebrates and invertebrates have been 

 garnered, facts and principles entirely unknown 

 to Darwin, and foreign to the logical mind of 

 Huxley as well, have been revealed ; in short, the 

 data of induction as to how nature does work 

 in the origin of certain new characters have to- 

 tally changed in paleontology perhaps more than 

 in any other biological field of observation. 



Two grand lines of observation have been fol- 

 lowed in paleontology quite independently of 

 each other : first, the minute changes in phyla of 

 invertebrates observed in fossil shells by Waagen, 

 Hyatt, Hilgendorf , Neumayr, and many others ; 

 second, minute changes in phyla of fossil mam- 

 mals observed by Osborn, Scott, Deperet, Mat- 

 thew, and many others. It is obvious that the 



