290 Criticism of Hypothesis of Linkage ami Crossing Over 



C O. N. C 0. 



1. 4.Ab SAc 2Ad \Ae QAB \AG 2AD SAE ^AF 



2. HAc 2Ad lAe SAB OAG lAJ) 2AE SAF 



3. 2Ad \Ae 2AB 2AG QAD lAE 2AF 



4. lAe lAB lAC IAD OAE lAF 



4'Ab GAc 6Ad iAe GAB 4AG ^AD GAE \OAF 



The percentages of cross-overs become 



Ab 4 CO. ,„„, „ 



= 40 /„ ot cross-overs 



= 60% 



= 60% 



=40°/ 



AE 6 N. C O. '" 



The series of percentages is a symmetrical one, but the terms are 

 not in an arithmetical progression. 



If we take twenty-six factors, A to Z, instead of six, A to F, we get 

 the following series : 



