576 



THE AMERICAN NATURALIST [Vol.XLVI 



ratio. In the degree of association between the char- 

 acters, however, no such uniformity was exhibited. 

 Leaving out of consideration two families represented 

 by only a few individuals, the coefficient of association 

 varies from .910 to .990. In terms of gametic coupling 

 this shows a range from 6: 1 to 16: 1, and since the series 

 as a whole accords with a 12 : 1 ratio it is not apparent 

 why only 7 : 1 and 15 : 1 ratios are considered. 



Individuals were again selected from two of the fam- 

 ilies which showed the highest correlation, and grown the 

 following season. The progeny from the first family 

 behaved irregularly and the presence of some disturb- 

 ing process was suspected, though the deviations with 

 respect to the individual character pairs were less than 

 the probable error. 



The second family gave individuals with the follow- 

 ing grouping (Bateson, Saunders and Punnet t, p. 12) : 

 583:26:24:170 (association .987 ±.0026). Of this it 

 is said: 



It is obvious that the numbers in this group of families accord very 

 closely with the figures expected on a 15 : 1 : 1 : 15 basis, and the 



fro] , the distribution o/the pollen and color characters in F u n lies 

 from the Bush X Cupid crosses where the following figures were ob- 

 tained: 131:6:5:42. (Association .989 ± .005.) 



Here again when it is said that the figures " accord 

 very closely," it can only be meant that they accord 

 closely with one of the formula? in the hypothetical series 

 as compared with other members of the series. The 

 numbers are, of course, inadequate to afford evidence as 

 to whether the observed figures accord more closely to 

 those resulting from a 15:1 combination than they do, 

 for example, to a 16:1 or a 14:1, yet the results are 

 taken to support the original assumption that the group- 

 ings are in powers of two. 



The examples of gametic coupling thus far reported 

 are summarized by Bateson and Punnett as follows 

 (1911, p. 5) : 



