194 Albinism in Maize 



condition which he terms " albomaculata." Occasionally there may 

 appear a plant which is either wholly gi-een or wholly white. 



Anatomically it appears that this variegation is due to the fact that 

 in the whitish areas of the leaf the chromatophores are not green, but 

 are more or less bleached. The boundary between the green portion 

 and the white portion of a leaf is not sharp and distinct, but is gi-adual ; 

 the cells on the boundary may contain pale-green chromatophores, and 

 even in the same cell the intensity of colour of the different chromato- 

 phores may vaiy. A pure green branch remains so, and one which is 

 pure white remains white. 



Seed from one of the gi-een branches produces green seedlings which 

 in further generations breed true. Seed from white branches produce 

 white seedlings which soon die because of their inability to perform 

 photosjoithetic processes. Seed from a variegated branch produces 

 some seedlings which are yellowish-white, some which are gi-een, and 

 some which are spotted or variegated. 



In crosses Correns found that this variegated condition was inherited 

 only through the mother. When a flower on a white branch was 

 pollinated with pollen from a normal green plant, only white seedlings 

 were produced. And in the reciprocal cross, when a flower on a green 

 branch was pollinated with pollen from a flower of a white branch of 

 the variegated plant, only green seedlings were produced. But the 

 seedlings were known to be hybrids because of the behaviour of other 

 characters, e.g., colour of the flowers. These gi-een hybrids bred true 

 to the green character in succeeding generations, while the other 

 characters behaved as ordinary hybrids. 



Baur(4) believes that in Primula sinensis he has a case analogous 

 to that described by Correns in Mirabilis, but at the time of his publica- 

 tion he had not fully investigated it. 



Soon after the account of Correns concerning the case of non- 

 Mendelian inheritance in Mirabilis, Baur (-5) described another peculiar 

 form of non-Mendelian inheritance in Pelargonium zonule. Among 

 these plants there sometimes occur bud sports which are full}- white. 

 Seeds from the flowers on a white branch produce pure white seedlings. 

 Also the white-leaved form remains constant if grafted upon a green 

 plant. 



Reciprocal crosses between this white-leaved form and a constant 



green form gave seedlings which had a mosaic design of green and 



white. Baur makes it apparent that in the ^i there was a vegetative 



^segregation, the plants being composed of green and white mosaic areas. 



