PREFACE 



This book is a modest attempt to show that there is one 

 Evolutionary Principle ruling in all Nature ; that, true 

 to this principle, all Matter has, as it were, evolved into 

 being, and the many fundamental species of dead and living 

 Matter have been differentiated. Also, that the outstanding 

 phenomena of living Growth and Reproduction reflect the 

 action of the Common Factor behind all Evolution. 



The greater part of the book is, however, concerned 

 with the evolution of living Species, and the development 

 of the theory that this is based on our fundamental evolu- 

 tionary principle, the Evolution of Continuity. 



It is curious that though the general principle of 

 Natural Evolution is on an unshakeable basis, the bed- 

 rock of the process has never been clearly displayed. Perhaps 

 one explanation of this may be that all workers have been 

 under the influence of the aphorism, " Natura non facit 

 saltum." Thus, attention has been specially given to 

 resemblances between nearly related types and, following 

 Darwin's lead, to the variation resulting from artificial 

 selection ; it being taken for granted that if we could see 

 all the past evolutionary road, this would be revealed as 

 a continuous chain each of whose links was a step onwards 

 in a more or less gradual transformation. The specially 

 large gaps in the road are attributed to lost evidence, to 

 an imperfect geological record, and their mystery has been 

 accepted as impenetrable in the continued absence of new 

 fossil discoveries. 



