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1922] RANDOLPH—MAIZE 339 
and .white branches occurring on the same plant, the resulting 
progeny always resembled the branch which produced the female 
gamete, regardless of the way in which the cross was made. The 
results obtained showed clearly that, so far as chlorophyll characters 
were concerned, the offspring were not affected by the pollen. 
CORRENS explained these results by assuming that the absence of 
chlorophyll was due to a cytoplasmic disease, which, although 
manifesting itself in the plastids, may or may not be limited to 
these organs. The diseased condition is accordingly transmitted 
from one generation to the next only through the egg cytoplasm, 
the male parent not affecting the character of the offspring, since 
no male cytoplasm is brought into the egg at the time of fertilization. 
A situation similar to this was described by BAuR (3) in Antir- 
rhinum majus albomaculata and Aquilegia vulgaris, and also by 
GREGORY (23) in Primula sinensis. These workers, however, are 
inclined to the view that two kinds of plastids, diseased and normal 
ones, become segregated during somatic mitoses to different cells 
and consequently to different regions of the plant tissue. This 
results in the variegated appearance common to plants of these 
strains. The diseased plastids are described by GREGORY (23, 
pl. 10, fig. 10) as being pale yellow and smaller than the normal 
plastids. In young actively growing leaf tissue both kinds are 
present in the same cell. Another interpretation should be placed 
on these figures of GREGORY, as will be discussed later. 
A somewhat different case is that reported by Baur (2) in 
Pelargonium zonale albomarginata. In this form plants occur 
which have green branches and entirely white branches. Flowers 
borne on either green or white branches when self-fertilized produce 
offspring in succeeding generations which are like the original 
branch, When, however, crosses are made between green and white 
branches, mosaic seedlings (green and white) result, regardless of 
the way in which the cross is made. This case differs from that of 
Mirabilis in that the inheritance is not the maternal type. Here 
both the male and female gametes must be concerned in the trans- 
mission of the character. Baur is led to assume that plastids 
rather than the nucleus are directly responsible for this unusual 
type of inheritance, and that they are brought in by the male 
