CHAPTER I 

 THE PROBLEM 



The organic world appears in the form of more or less 

 clearly defined and limited and more or less complex 

 entities which for lack of a better name we call individ- 

 uals. The individual is not necessarily a single whole 

 organism; it may be a part of a cell, a single cell, or a 

 many-celled organ or complex part of the organism; 

 or, as in most plants and some of the lower animals, a 

 number of organisms possessing certain organs or parts 

 in common, and therefore remaining in organic con- 

 tinuity with each other, may together constitute an 

 individual. In at least most organic individuals a 

 more or less orderly series of changes in structure and 

 behavior which comprise the life-history occur, and in the 

 course of these changes the individuals may give rise to 

 new individuals by some sort of reproductive process. 



In order to define the problem of the organic indi- 

 vidual, it is necessary to inquire whether any funda- 

 mental identity or similarity is discoverable in all 

 individuals and whether the changes which they undergo 

 are subject to any general laws which we can at present 

 apprehend. 



THE CHARACTERISTICS OF THE ORGANIC INDIVIDUAL 



The term *' individual," meaning in its etymological 

 sense something undivided or which cannot be divided, 

 is open to various objections. Division of individuals 

 to form new individuals is a characteristic feature of 



