Wallflower and Cabbage 85 
and the ornamental” are leafless; at the same time, 
they and the insects that feed upon them are making 
use of solar force and converting it by their vital 
chemistry into material whereby the soil is enriched 
for more important plants. 
The Wallflower (Cheiranthus cheiri) is perfectly 
well known to all, although, strictly speaking, it is 
not a native plant, but for more than three centuries 
it is known to have been growing wild upon our 
old walls. It is a perennial plant, the lower part of 
its stems being shrubby and enduring. _ Its leaves 
are simple, of a narrow lance-shape without stipules, 
arising alternately from the stems. Respecting the 
number of the organs in all this large family of 
Crossworts (Crucifere), there has been considerable 
discussion whether 
it should be re- 
garded as two, or 
four, or a reduction 
from an originally 2 
larger number, aes 
though four ap- 
pears to be the more 
generally accepted = 
number. There are 
four sepals in two 
pairs, four petals 
arranged crosswise, : 
and six stamens— Wallflower 
two being held, on i 
the tetramerous 3 
hypothesis, to have been suppressed. Though the 
ovary is usually one- or two- celled, it is believed to 
