52 



n (total) 



where n indicates the number of the specified viral types, p(h) is the propor- 

 tion of the yield containing the h allele, and 1— p(A), p(r), and 1 — p(r) are re- 

 spectively the proportions containing the h + , r, and r + alleles. The fraction 

 p(A) is equal to 1— p(r) if the numbers of the two recombinant types are the 

 same, or approximately equal if these numbers are small. A fair idea of the 

 complete distribution of alleles is therefore given by the distribution of p(A) 

 alone. Two examples of this distribution, showing the proportions of the h 

 allele in different single bursts for the crosses hXrl and hXr7, are given in 

 fig. 6. 



9 18 27 36 45 54 S3 72 81 90 S3 100 

 per cent K virus 







18 



27 36 45 54 63 72 81 90 



per cent h virus 



Figure 6. — Distribution of proportions of h virus in yields from single bacteria. 



100 



246 



