THE FERTILISATION OF CERTAIN PLANTS. 55 
the same part of a bee which above would be struck by the 
anthers. 
Besides these male and these female flowers, others will be 
found — usually intermediate in position — which appear to be 
fairly hermaphrodite. In these not only do the anthers ripen 
their pollen, but the pistil, though it is not nearly so large as in 
the purely female flowers below, yet matures and is often fer- 
tilised. It is not without its use that the flowers which are 
becoming male should be at the apex, and those which are 
becoming female should be at the base of the spike ; for thus 
any pollen which is shaken out by the wind will have a better 
chance of being utilised than were the positions reversed, as in 
poterium. 
A word as to the dabs of bright colour on the upper petals. 
It is so excessively common to find such ornaments about the 
entrance into the nectary of flowers that one can hardly help 
suspecting that their position in that part serves some useful 
purpose. May it not be that the colour acts as a guide to the 
insect, attracting and directing it to the proper entrance ? The 
marvellous ease and rapidity with which insects find their way 
to the nectary would thus in part be explained. A fact given 
by Mr. Darwin, as a striking case of correlation, seems to me 
strongly in favour of the explanation I have advanced. “ I 
have recently observed,” says Mr. Darwin, “ in some garden 
pelargoniums that the central flower of the truss often loses the 
patches of darker colour in the two upper petals, and that when 
this occurs the adherent nectary is quite aborted ; when the 
colour is absent from only one of the two upper petals, the 
nectary is only much shortened.” * 
I should say that in pelargonium, as in a host of other 
flowers, the anthers shed their pollen before the stigma is 
mature ; and that anthers and stigmas turn when mature 
upwards, so that a bee, in getting to the nectary, rubs them 
with the under surface of its body, and thus carries the pollen 
of the younger flowers to the stigma of the more advanced 
ones. 
EXPLANATION OF PLATE LYI. 
Fig. 1. Pedicularis sylv. Longitudinal section, (a) point, which probably 
protects the stigma during egress of bee ; (6) anterior filament, 
with hairs on its upper part where it passes under the lower 
anther (f) to terminate in the (e) upper one ; (c) posterior fila- 
ment, without hairs on the upper part ; (d) style ; ( e and/) upper 
and lower anthers. The cells are open and face the spectator. 
* “ Origin of Species,” p. 145, 
