A TJirec-fokl Development. 15U 



has now anywhere on our earth a home; all became ex- 

 tinct millions of years ago. From the first forms of life 

 back in the dim and mysterious ages of long ago, up 

 through all the intervening ages to the close of the Ter- 

 tiary age, development was in body, in bone and muscle, 

 and finally reaching its limit, the continuing change of 

 the inorganic world overwhelmed and extinguished near- 

 ly all of it. 



The sudden changes in organic beings, the apparent 

 destruction of a whole world of life, which we find so 

 many times in the geological ages of the past, is apt to 

 mislead many students who study the past life of our 

 world. We must liken the record which we have on this 

 subject to a book, from which whole chapters in some 

 parts have been torn away, and in other places pages are 

 missing, while in still other parts sentences and words 

 are gone or transposed. If several like books were treat- 

 ed in that way, with the mutilations made at random, it 

 might be a not very difficult matter to gain a knowledge 

 of the whole subject by studying all of them together, 

 and so learning in one what was lacking in another. So 

 it is in our geological record. Leaves missing in one 

 country or section may be found in another and thle 

 storj'^ thus completed sufficiently for us to understand 

 the most of it. There should be no surprise that our 

 knowledge of the past life history of the earth is so in- 

 complete, that there should be so many missing links. 

 It should be remembered that few land animals are pre- 

 served and fossilized, and also that only a small part of 

 the earth's surface has been at all closely examined. 

 This very lack of evidence, and the difficulty of finding 

 it, makes the study of paleontology one of the most in- 

 tensely interesting pursuits that the student of science 

 can follow. 



Near the close of the Cretaceous period a new order 

 of terrestrial beings are first found. From this order, 

 or with it, was later to be developed the highest foi-ui 

 of life which has thus far had a home on this earth, an 

 order that should be above and rule all other beings of 

 this world. A new era has dawned, the era of brain. 

 Muscle and bone has been carried to the extreme limit 

 and proved insufficient. Brain must now take the place 



