39 



more important than fossils for charactei'izing formations ; 

 while Bakewell, later yet, defines Palaeontology as comprising 

 " Fossil Zoology and Fossil Botany, a knowledge of which may 

 appear to the student as having little connection with Geology." 



During the later half of the third period, greater progress 

 was made, and before its close Geology was thoroughly estab- 

 lished as a science. Let us consider for a moment what had 

 really been accomplished up to this time. 



It had now been proved beyond question that portions at 

 least of the Earth's surface had been covered many times by 

 the sea, with alternations of fresh water and of land ; that the 

 strata thus deposited were formed in succession, the lowest 

 of the series being the oldest ; that a distinct succession of 

 animals and plants had inhabited the earth during the different 

 geological periods ; and that the order of succession found in 

 one part of the earth was essentially the same in all. More 

 than 30,000 new species of extinct animals and plants had now 

 been described. It had been found, too, that from the oldest 

 formations to the most recent, there had been an advance in 

 the grade of life, both animal and vegetable, the oldest forms 

 being among the simplest, and the higher forms successively 

 making their appearance. 



It had now become clearly evident, moreover, that the fossils 

 from the older formations were all extinct species, and that only 

 in the most recent deposits were there remains of forms still 

 living. The equally important fact had been established, that 

 in several groups of both animals and plants, the extinct forms 

 were vastly more numerous than the living ; while several orders 

 of fossil animals had no representatives in modern times. 

 Human remains had been found mingled with those of extinct 

 animals, but the association was regarded as an accidental one 

 by the authorities in science ; aud the very recent appearance 

 of Man on the earth was not seriously questioned. Another 

 important conclusion reached, mainly through the labors of 

 Lyell, was, that the earth had not been subjected in the past to 

 sudden and violent revolutions ; but the great changes wrought 



