333 



planes of division occur may indicate variations in the process 

 of segregation. *) 



3. We do not yet know whether independent reduplicatecl 

 Systems can be formed in the same individual. In the Sweet 

 pea for instance we have not yet seen the consequences of com- 

 bining blue, erect Standard, and long pollen with the Fertile- 

 sterile, Dark-light axil series, and much may be discovered when 

 such families come to be examined. 



Animals. 



The phenomena seen in animals may well be produced by 

 the segmentations in which the parts of the ovary or testis are 

 determined. Hitherto no case of coupling has been found in 

 animals. Among the phenomena of repulsion however, of which 

 many examples exist, certain suspicious cases have been observed 

 which may mean that in animals reduplicated Systems exist like 

 those of the plants. Nevertheless at present it seems not impos- 

 sible that the two forms of life are really distinguished from each 

 other in these respects. 



Terminology 



Lastly, in view of what we now know ; it is obvions that the 

 terms „coupling" and „repulsion" are misnomers. „Coupling" 

 was first introduced to denote the association of special factors, 

 while „repulsion" was used to describe the dissociation of special 

 factors. Now that both phenomena are seen to be caused not by 

 any association or dissociation, but by the development of certain 

 cells in excess, those expressions must lapse. It is likely that 

 terms indicative of differential multiplication or proliferation will 

 he most appropriate. At the present state of the enquiry we 

 hesitate to suggest such terms, but the various Systems may con- 

 veniently be referred to as examples of reduplication, by 

 whatever means the numerical composition of the gametic series 

 may be produced. 



*) c. f. Coulter and Cham be riain, Morphology of Angiosperms 

 1903, p. 187. 



