OEDEE AND SUCCESSION OF LIFE. 



LIFE, ITS NATURE AND FUNCTION INTERDEPENDENCE OF PLANTS 

 AND ANIMALS HARMONY OF THEIR RELATIONS THEIR EXISTING 

 ASPECTS AND DISTRIBUTIONS ASPECTS AND DISTRIBUTIONS OF 

 THE PAST ADVANCE IN TIME FROM LOWER TO HIGHER FORMS 

 ORDER OF THIS PROGRESSION THEORIES OF LIFE-DEVELOPMENT 

 HOW FAR PROBABLE LAW OF CREATIONAL PROGRESS PROOFS 

 OF ITS EXISTENCE UNIVERSALITY OF ITS OPERATIONS ALIKE III 

 THE PHYSICAL, VITAL, AND INTELLECTUAL ITS ENDURANCE. 



HOWEVER interesting it may be to trace the material changes 

 to which the crust of the earth has been subjected, this in- 

 terest falls infinitely short of that excited by the study of 

 the life-forms by which its surface has been successively 

 peopled. In the one case we know something of the forces 

 by which the changes are produced, and the modes in 

 which these forces operate ; in the other we perceive only 

 the external conditions under which plants and animals 

 exist, but we know nothing of the origin of Life, and as yet 

 very little of the causes concerned in the numerous varia- 

 tions and aspects it has assumed. In the one case we can, 

 to a certain extent, mould and modify the operating forces ; 

 in the other, vital action is altogether beyond our produc- 

 tion, and we can modify its variations only in the slightest 

 and most temporary degree. In the one case we have 

 masses that are operated upon from without ; in the other, 

 forms that are actuated by impulses from within, and, in 



