234 
HARLEY HARRIS BARTLETT 
Nutt., which was treated in American floras for decades as Oe. biennis 
var. cruciata T. &. G. De Vries evidently anticipated that no con- 
fusion would result from the use of the name Oe. biennis var, cruciata 
a second time, because of the fact that he was recognizing the former 
var. cruciata as a species. That misunderstanding has arisen is clear 
from the following extracts from Davis' article: . . we find that 
the so-called ' mutants ' were not derived from the pure Dutch biennis 
of the sand dunes but from a cross between this race and a type desig- 
nated 0. biennis cruciata. This fact seems to the writer of fundamental 
importance in judging the conclusions of Stomps. It should be made 
clear that the form ' 0. biennis cruciata ' is recognized in the more recent 
taxonomic treatments as a true species sharply distinguished from 
types of biennis by its floral characters. Whatever may have been 
the origin of 0. cruciata or its possible relationship to 0. biennis, a 
cross between these types must certainly be regarded as a cross between 
two very distinct evolutionary lines and its product a hybrid in which 
marked modifications of germinal constitution are to be expected. . . . 
Stomps assumes that the cruciata in Holland is a mutant from the Dutch 
biennis, but his belief rests upon no direct evidence. Cruciata has 
never appeared in the extensive cultures of the Dutch biennis grown 
by de Vries and Stomps. Neither have we any direct evidence that 
the American cruciata has come from any form of biennis. It is true 
that the species cruciata and biennis appear to be closely related, but 
it is equally clear that they constitute very distinct lines each with a 
long period of evolutionary independence. I cannot see the justifica- 
tion for Stomps's attitude when he treats a cross between the biennis 
and cruciata of the sand dunes of Holland as though it were the com- 
bin^-tion of forms within the same species which have similar germinal 
constitutions. Stomps lays emphasis on the purity of his material 
. of biennis and cruciata which had been carried along for several years 
in pure lines from original wild plants of the sand dunes. He states 
that the crossing of these two forms is concerned alone with the floral 
peculiarities of cruciata, since in all other characters the two types are 
the same. It seems to the writer hardly possible that lines so well 
established as biennis and cruciata can be absolutely the same in all 
respects except that of flower form, although this is obviously the most 
important point of difference. The American forms of cruciata are 
exhibiting among themselves remarkable differences of germinal 
constitution." 
As already stated, the writer has cultivated Oe. biennis var. 
