338 CARL HALLQVIST 


assumption that the colour of the F/-plants may be intensified to- 
wards full blue colour. That is to say that the Fj-stage is more 
modifiable and therefore varies more than the FF-stage. Thus the 
transition to the Fj-stage is noticeable, though the main part of the 
colour dilution is due to the complete absence of the F-factor. This 
is true only of the blue colour, however, but not of the bluish-red 
type. I have not yet been able to distinguish the vvFf-types from the 
vvFF-types in spite of careful observations. The case of incomplete 
dominance mentioned is the only one found in Lupinus; the domi- 
nance is complete as to all other characters to all seeming. 
The pleiotropic effect of the colour factors have already been 
mentioned; they give rise to coloration not only in the flowers but 
also in the sepals, in the cotyledons, in the axis etc. The R- and B-fac- 
tors also influence the colour of the seed. The phenomenon is very 
common. WHELDALE Cites 14 different genera, where a genetical con- 
nection between flower colour and anthocyan in vegetative parts has 
been found; they do not all represent pleiotropic phenomena, however. 
Among these genera intensifying factors and full colour factors have 
been found in Antirrhinum and Primula, and these factors influence 
also the coloration of the vegetative parts. I have not been able to 
find any data as to the eventual weakening of the colour in the leaf 
axils in Lathyrus, when the full colour factor is absent; this is the 
case in Pisum, however. A weakening of the colour of the flower is 
probably in most cases followed by a weakening of the colour of the 
vegetative parts. This is not the case in Lupinus, however. While 
the absence of the F-factor gives rise to a very marked dilution of the 
flower colour, which almost disappears in the beak of the keel, no 
trace of such a dilution is found in the vegetative parts of the plant. 
The faint coloured tinged red type has just as dark earth-brown seeds 
as the deep blue coloured type, and the colour of the bracts is identi- 
cal with the colour of the bracts in the full coloured bluish red type. 
Thus a factor regulating the colour intensity of another pleiotropic 
factor influences the effect of this factor to different degrees in diffe- 
rent organs. In one organ, e. g. the beak of the keel, every trace of 
the colour disappears although normally coloured intensively; in 
another organ no change in the colour is seen in spite of the fact 
that the colour often is very weak in the full coloured type, for 
instance in the stem, where only a faint tinge of colour covers the 
green ground. In still other organs, e. g. standard and wings, the 
