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Figure 8. Proportions of Dolichos-negative cells in subjects 

 G.P. and A.R. 



bean extract, and the negative ones inagglutinable. He could give the 

 pigeons wholebody X-ray, and when he did that, he got the same 

 kinds of results as shown in this figure: initial increases falling down to 

 a stable level, above the preirradiation level in all his cases. 



I don't have his graphs here, but I can show what some of the 

 levels were. He recently published in Science, and you may have seen 

 these data (Table 1) and some additional ones (33, 34). The pigeons, 

 by and large, have higher frequencies than people do, if you use 

 pigeon cell carrier. You can also use human A cell carrier. Then, they 

 have frequencies more or less similar to people. But in any case, no 

 matter which carrier is used, a long time afterward — this is 220 days, 

 430 days, 206 days, and so forth — you have large stable increases in 

 the negative cells in basically Phaseolus-positive pigeons. These in- 

 creases are much greater than you would anticipate on the basis of 

 specific locus induced mutation rate, and that is why they are so 

 confusing. 



