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University of California Publications in Botany [Vol.5 



expectation. The other population exhibited an anomalous type of 

 segregation, and gave 2 red : 23 white. It is unfortunate that this 

 line was not investigated further, but the results probably are due to 

 an experimental error. 



TABLE 20 



Fs SOWINGS OF THE ALBA-MACROPHYLLA SERIES. 



Eight families of Fo plants were grown from pink F^'s. Of these 

 F, plants six proved to belong to the RrWw genotype. The totals 

 from these six populations, viz., 35 red : 74 pink : 34 white, are in fair 

 agreement with the dihybrid ratio 3 red : 9 pink : 4 white. One of 

 the other populations gave 3 red : 22 pink. It was probably the result 

 of sowing seed from an Fo plant of the genetic constitution RrWW 

 which should give 3 pink : 1 red. The observed segregation ratio is 

 not good, but the numbers are small. Two sowings of F3H24P.-,4P2o 

 gave totals of 33 pink : 9 white. The F. plants in this case must have 

 been of the genetic constitution RRWw; in which case expectation 

 would be 3 pink : 1 white. No selection was observed to breed true 



