Buttercups and Columbines 75 
There is a somewhat similar arrangement in the 
Larkspur (Delphinium ajacis), but the blue, pink, or 
white flowers have undergone some modifications, 
becoming irregular and less perfect. There are still 
five coloured sepals, one of which has developed a 
long tubular spur, but there are only two petals, each 
with a spur which is laid inside that of the sepal, 
where it secretes honey. At their lower part these 
petals come close together, but leaving an opening 
to the spur higher up. The lower sepals constitute 
an alighting-place for bees whence they can climb 
the lower part of the petals and push their tongues 
down the tube to reach the honey, but as in Columbine 
the stamens and finally the solitary stigma are elevated 
in succession, so that they come in 
the way of the bee’s proboscis, 
and cross-fertilisation is thus 
effected. In some other species of 
Larkspur the employment of four 
petals more effectually bars the 
way to the spur from below. | 
Monkshood (Aconitum napel- 
lus) is specialised to the same end 
as Columbine, yet with an entire ( 
difference of form. The five sepals 
are coloured deep blue and are of 
varying shape; one which takes 
the uppermost position in the very 
irregular flower has become an 
arched hood large enough to con- 
tain all the others in the bud. 
There are only two petals, and these have been 
converted into hammer-shaped nectaries hidden 
Monkshood 
