SHORTER ARTICLES AND DISCUSSION 



TABLES OF LINKAGE INTENSITIES 



In the July, 1916, Naturalist, Professor Emerson gives con- 

 venient formulae for calculating linkage intensities. His formula 

 (I) is especially useful because it is applicable either to cases of 

 coupling or to cases of repulsion. I had independently worked 

 out empirical formulae for calculating coupling and repulsion 

 which are very similar to that given by Emerson : indeed they are 

 identical with it, if 1 is substituted for r in cases of coupling and 

 for s in cases of repulsion. I had failed to observe, what Emer- 

 son shows, that the two formula' may be iriven a single generalized 



TABLE I 



series, so that when a suspected case of coupling or repuUion 

 comes to notice the nearest integral gametic series can at once be 

 determined by inspection of the table, without making the calcu- 

 J coupling. ^ ^ ^ • h - h A and B are due to a single 



575 



