126 
S. IKENO : 
we have 12 + 2 + 45 = 59 oranges and 30 whites (expected, 66'75±4 : 22-25±4). 
The production of some magentas and reds in this case may he explained if 
we will assume that a certain number of the gametes of the composition CMM, 
and CMb have arisen on account of the reversion of one or two allelomorphs, 
and the fertilisation, such as CMS x Crb, CMM x erb, CMb x Crb 
CMb x crb have taken place. Almost the same might perhaps be said in 
respect to No. 26, though it contains too few individuals to lead us to a 
somewhat probable conclusion (compare Table VIII, that No.) The result 
of No. 30 'may be explained in an almost similar way ; its normal gametes 
are ( Mb and Crb, and we have 33 reds and 9 oranges, expected 3T5±2-8 
and 10-5 ±2-8, if we will reckon 1 magenta among the reds ; this magenta 
was produced because at least one gamete CMM has arisen by reversion. 
In respect to the production of magentas from whites, as we see in Nos. 
3, 5 (jV), 8 (i^), and 28 we must assume the simultaneous reversion of three 
allelomorphs c, V and b into C, M and M respectirely, though here on account 
of the complete linkage of M and M the whole process will be reduced to the 
reversion of one factor and one factor-complex. Suppose that on account of 
this process few gametes CMM are produced besides normal ones crb ; the 
fertilisation between CMM and crb which will be the most prevailing one 
will give magenta of the constitution CcMrMb, whilst very rarely the 
fertilisation CM M X CM M, i.e. that between two mutated male and female 
gametes might take place. To the latter category may belong No. 5, because 
here the magenta produced in F, from a seed taken on 1 white F 2 plant 
seems to breed true in F 4 , the offspring in the latter generation consisting 
wholly of magentas (32 in all), though it would not be impossible that all 
other segregates did not come to germination. 
In No. 28 few oranges and magentas were produced from whites of the 
composition ccrrbb. Here it must be assumed that a small number of 
gametes of two kinds, viz. Crb and CMM were simultaneously produced 
besides normal ones crb, and that the fertilisations Crb x crb as -well as 
CMM X crb (or their reciprocal) have take place. 
In No. 8 1 magenta derived in F, from 1 F, white was found to 
segregate into 103 magentas and 22 reds, whence it may be inferred that 
this magenta parent might be of the constitution C CMM Mb, though the 
