332 CARL HALLQVIST 
blue. While the bluing effect of the B-factor is rather weak in the 
flowers, requiring the co-operation of the V-factor in order to produce 
the deep blue colour, no such co-operation is required in the case of 
the seeds. Blue seed colour is found in bluish red plants as well as 
in quite blue plants, and the colour has the same intensity in 
both cases; it is not possible to tell the particular type of flower colour 
from the colour of the seeds. 
The V-factor transfers the pure red flowers colour into violet. It 
is not a question of a mixing in this case, apparently; the ground 
colour is probably wholly transferred into a new pigment. It is true 
that a faint tinge of blue is sometimes found also here, but the ground 
is always violet and not red. The V-factor does not influence the 
seed colour, and the rust-brown colour remains therefore quite un- 
changed. 
It is of great interest to draw a parallel between the flower colours 
of different species and genera even if the accuracy of such a parallel 
becomes doubtful for want of chemical investigations. The studies of 
WILLSTÂTTER in the chemistry of the flower colours have showed a 
remarkable correspondence in the composition of the pigments in dif- 
ferent genera. It appears very probable that the flower colour of 
Lupinus, although not analyzed chemically, presents similarities with 
numerous genera investigated by WirLLstÄTTErR as to the composition 
of the pigments. The colour scale of Lupinus corresponds exactly with 
the scale found in Centaurea and Delphinium; the assumption of a 
correspondence as well in the chemistry of the pigments between Lu- 
pinus and the latter genera does not seem to be too bold. 
The following points of comparison between the genetical scheme 
found in Lupinus and the chemical scheme of WiLzSTÂTTER would 
then be held forth. The R-factor in the pure red type would be made 
responsible for the occurrence of acid cell sap and for the presence 
of the anthocyanin in the form of a homologue to the oxonium salt, 
which has been found to form the red pigment in Centaurea. The 
V-factor would cause a basic influence on the cell sap neutralizing the 
acid of the pure red type and liberating the anthocyanin, which now 
gives violet colour. The B-factor would also cause basic effect, as 
the blue colour found with this factor and caused by a calcium salt 
with the anthocyanin as a base requires alkaline cell sap. The B- 
factor alone, however, produces alkaline cell sap only in some of the 
cells of the flower. The result is a blue tinge on red ground, which 
gives rise to the compound colour bluish red. It seems quite natural 
