194 THEORETICAL BIOLOGY 



sion, for the genesis is a process in which new part-processes 

 continually appear in conjunction, or else release one another. 

 These processes are carried out in the living material exactly as 

 they are in the non-living, when our implements take origin. 



But if we inquire whence comes the impetus for the various 

 processes, morphology tells us that it cannot come from an 

 agent placed outside the material in space, since the con- 

 struction takes a centrifugal direction, and not a centripetal, 

 as is the case with implements. 



Every process in the animal body is led up to by a 

 chemically demonstrable change, produced in many cases by 

 substances which we call ferments, present only in minute 

 quantities. All of which indicates that we must not reject 

 the hypothesis of there being impetus-giving ferments ready 

 prepared in the germ, which control the physical as well as 

 the chemical changes during the genesis of the animal, and 

 supply the cause of all the part-processes that go to make up 

 the process of development as a whole. 



It is to be noted that during cell-division the ferments 

 pass from cell to cell, and a sorting takes place, so that finally 

 there are cells with only a few, isolated ferments. These final 

 ferments introduce the micro-chemical processes which trans- 

 form the last resulting cells into the definitive framework. 



Thus far one simple chemical hypothesis will suffice. 

 But a fundamental fact stands in the way : the finished 

 cell is not an independent structure, but, as soon as it has 

 reached complete development, it is connected, conformably 

 with plan, not only to its neighbours but to all the cells of the 

 body. This result could be achieved only if initiation of the 

 various part-processes during genesis went on in perfect 

 accordance with plan ; and this again presupposes a hidden 

 framework in the ferments that give the impetus. 



While cell-division goes on, the formation of the germinal 

 areas begins, which are to be considered as genetic building- 



