142 Report of the State Geologist. 



honor he deserves, and adopt, along with the new data, the 

 greater part of his ideas, even those which Darwin rejected. To 

 this latter belongs the honor of having discovered one of the 

 most important factors of Evolution, namely, the phenomenon of 

 natural selection. He has furthermore this advantage, that he 

 fortified his theories with very numerous observations, with 

 long and patient experiments, that he presented them in a deduct- 

 ive form without the intervention of hypothesis, and that he 

 developed them with unanswerable logic. All this, in our opin- 

 ion, explains the success of Darwin in a matter where his prede- 

 cessors failed. He certainly followed the best method, since he 

 proved himself able to overcome all opposition, and to him is due 

 the great transformation which the purpose of biologic and 

 palaeontologic researches has everywhere undergone. 



Third period. — It would be impossible for us here to cast even 

 a rapid glance over the progress realized during this last period, 

 which, beginning toward the year 1857, continues to the present 

 day. The two following chapters will be devoted to the explana- 

 tion of the present state of ideas admitted by the transformist 

 school of scientists, in so far as these ideas are confirmed by 

 palaeontologic testimony, or give to the data furnished by this 

 science an especial synthetic character. But it must be said that 

 purely descriptive researches have not ceased to be held in honor, 

 and that the number of types described increases with a rapidity 

 of which it is difficult to form an idea. The Annuaire Geolog- 

 ique mentions 7c55 palaeontologic publications which appeared in 

 1889, and to this must be added the enormous number of 

 descriptions contained in works especially devoted to Geology. 

 One of the most striking characteristics of the present period is 

 the precision and minuteness with which observations are carried 

 out; efforts are made to derive from the examination of a fos- 

 sil all that can possibly be known of its morphology, structure or 

 development. A delicate method by thin sections is employed in 

 order to push as far as possible the descriptive analysis, the 

 younger forms are compared with the adults, and no technical 

 difficulty is able to daunt the investigator. 



Oa the other side stratigraphy has made such great progress 

 that the reappearance of forms both in time and place is better 

 understood. Variations of the same species in different localities 



