PREFACE 



This little volume has grown out of a need experienced by 

 the author during fifteen years of teaching paleontolog}^ He 

 has found that students come to the subject either with very 

 little previous training in biology, or at best with a training 

 which has not been along the lines that would definitely aid 

 them in understanding fossils. Too often fossils are looked 

 upon merely as bits of stone, differing only in form from the 

 rocks in which they are embedded. Hence to awaken interest 

 in them as once living animals and plants, connected by the 

 wonderful chain of evolution with the animals and plants now 

 living, has been the chief aim of the author's lectures and 

 laboratory work upon introductory paleontology which he here 

 presents. 



To this end certain living forms have first been discussed as 

 types of their phyla or classes with especial reference to those 

 features which will help the student to understand the related 

 fossil forms considered later. The response which these living 

 forms make to their environment is considered, where they 

 live, how their life is maintained and how they perpetuate their 

 kind. The relation of the soft body to the hard skeleton or 

 shell is especially emphasized, since it is largely through this 

 very intimate relationship that our interpretation of extinct life 

 is made possible. The student may thus reconstruct from the 

 hard parts preserved in the rocks the appearance of the once 

 living animal. The discussion has been kept as free as possible 

 from unnecessary technical terms. 



Beyond this work of showing how past life may be interpreted 

 by the life of the present, and beyond this first comprehensive 

 view of the animal and plant world, such a book as this need 



vii 



