60 



THE BOTANICAL MAGAZINE. 



(Vol. XXXI VNo. 401. 



Pedigree No. 40 



» 41 



„ 94 



„ 98 



Table 4. 



Magenta 

 44 

 51 

 11 

 26 

 41 



Yellow 

 10 

 11 



2 



7 

 12 



White 

 24 

 12 



7 



8 

 17 



Total 

 78 

 74 

 20 

 41 

 70 



Actual observ 173 42 68 283 



Theor. expect, as 9 : 3 : 4 159.19 53.06 70.75 283 



Deviation +13.81 -11.06 -2.75 



m a bs ± 8.35 + 6.57 ±7.28 



Deviat./mabs 1.605 1.683 0.378 



(The Yellow in the table includes the Baryta Yellow and the Light 

 Cadomium, and the Magenta includes the Magenta and the Deep 

 Magenta.) 



From the table 4 we can conclude that the Fj plant has two 

 allerom orphic ids relating the colour of the petal. If we denote 

 these two alleromorphic ids with Cc and Rr, then the F x plant is 



represented by CcRr. The gamates pro- 

 duced from such a plant are CR, Cr, cR, 

 cr ; and the F2 plants raised from them 

 will be as shown in the table 5. 



In the table 5, the following three 

 types of individuals are represented in the 

 ratio 9 : 3 : 4 : 



1. 9 individuals containing C and R. 



Table 5. 



Vr- 



CR 



Cr 



cR 



cr 



CR 



CR 

 CR 



to 



Cr 

 CR 



m 



cR 

 CR 



TO 



cr 

 CR 



TO 



Cr 



CR 

 Cr 



TO 



Cr 



Cr 



y 



cR 

 Cr 



TO 



cr 

 Cr 



y 



cR 



CR 

 cR 



TO 



Cr 

 cR 



TO 



cR 

 cR 



w 



cr 

 cR 



w 



cr 



CR 



cr 



TO 



Cr 

 cr 



y 



cR 

 cr 



10 



cr 

 cr 



IV 



2. 3 individuals containing C only. 



3. 4 individuals containing R only, 

 or neither C nor R. 



This ratio 9 : 3 : 4 is the very ratio 

 which was theoretically expected for the 

 table 4. 



Here we can assume, with great pro- 

 bability, that the id, C concerns the 

 formation of a pale yellow flavone deriva- 

 tion (the pale yellow petal), and the id 

 R that of the reducing factor 1 for the 



1) The word ' factor ' is used here in the sense adopted by Fujii (K. Fujii, on 

 the conceptions of "id" &c. [Japanese], Bot. Mag. Tokyo, vol. 34, No. 400, p. (100), 

 viz. a factor is a chemical substance, (e.g. chromogen) which is formed by the influ- 

 ence of the corresponding "id", and becomes a component which enters into the 

 reaction to produce a certain characteristic (e.g. red colour of a petal). 



to 3= magenta. 

 y = yellow. 

 w — white. 



