The Origin of Linaria Vulgaris Pcloria. 217 
garis hemipeloria, and always suddenly. The very gen- 
eral occurrence of this race and the fact that intermediate 
forms between it and the fully developed Pcloria have 
never been mentioned by botanists, give support to this 
hypothesis 
If this view is correct we have here a mutation which 
is not limited to a period but continues to appear from 
time to time during the course of the ages. Its appear- 
ance in every single case is independent of the others, at 
least so far as external conditions are concerned. In 
this sense it is polyphyletic. 
A point which favors this view is the fact that it is 
not a member of a definite group of mutations as are the 
subspecies of Draba vcrna, Viola tricolor and others. 
Linaria vulgaris, it is true, frequently gives rise to other 
kinds of variations such as the Pcloria ancctaria and the 
Catacorolla, both of which have occasionally appeared 
in my own cultures, but nothing is on record concerning 
the relation between these and the Pcloria ncctaria which 
I have studied. 
If we compare these results with those which we have 
described above for Antirrhinum inajits striatuin ( 14, 
p. 134), we see that Linaria I'nlg. hemipeloria is obviously 
a half race; and that L. vulg. peloria, whose partial con- 
stancy seems analogous to that of the striped snapdragon, 
may perhaps be regarded as parallel to this. These two 
races fluctuate so as to approach one another, so to speak, 
occasionally overstepping the common boundary either in 
single flowers (L. vulg. hemipeloria) or in whole plants 
(L. vulg. pel o Ha). 
^ 5JJ JJC 
We now come to the most important point to which 
our results and conclusions lead us namely the com- 
