No. 606] SHORTER ARTICLES AND DISCUSSION 371 



be of the same magnitude as a value taken from the upper range 

 of the allelomorphic distribution, though the two forces thus 

 chosen are, of course, no more identical than are two of Johann- 

 sen's h cans' which are of the same size hut belong to different 

 pure lines. It is then assumed that in those cells in which the 

 values of F<j and Fg are equal, the chromosome carrying F,, 

 should incorporate gene g as frequently as gene G, and in those 

 cells in which their normal order of magnitude is inverted, the 

 crossover incorporation should occur more frequently, depending 



this overlap is of such a per cent, that one per cent, of the 

 gametes are crossovers (%1 of the diagram). 



Now, in order to present the crux of the matter, let us proceed 

 with the analysis of the behavior of the crossovers produced in 

 the above experiment (see diagram, line 2). Let us mate a cross- 



