1. Data sent by Anderson, with supplementary data of mine, show that sr (chrom. 1) is to the left of P, rather than between P and br as previously announced, and suggest that ts2 is to the right of P. The following table includes the available data from three-point backcrosses:

F1 genotype 0 1 2 1,2 Total Author
 
P    +    br 242 71 108 28 449 Anderson
+  T1-5b   +   15.8% 24.1% 6.2%    
 
P    +    br 195 60 58 19 332 Anderson
+  T1-5c   +    18.1% 17.5% 5.7%    
 
+    +   T1-5b 178 89 88 20 375 Anderson
sr   P     +     23.7% 23.5% 5.3%    
 
+    +   T1-5c 116 64 36 14 230 Anderson
sr   P     +     27.9% 15.7% 6.1%    
 
+    +   T1-9a 80 21 39 6   Anderson
sr   P     +   50 17 14 1   Emerson
  130 38 53 7 228  
    16.7% 23.2% 3.1%    
 
+    +   T1-9c 97 24 5 3 129 Emerson
sr   P     +     18.6% 3.9% 2.3%    
 
P   ts2    +   97 1 18 0 116 Emerson
+    +   T1-9c   0.9% 15.5%      
 
P    +  T1-10b 232 3 41 0 276 Emerson
+   ts2   +               
             
P   ts2   +    169 2 29 0 200 Emerson
+    +  T1-10b 401 5 70 0 476  
    1.1% 14.7%      

There is some question about the locus of what is here designated T1-10b. If it is between P and br as previously announced, then ts2 must be to the right of P. It is certain that sr is to the left of P, thus adding about 25 units to the length of the known linkage map of chrom. 1 and making it now approximately 150 units.