Violets and Pansies IOI 
is a large round head, having a mouth-like orifice 
near the front with a prominent lip to it, and a tuft 
of hairs on either side. 
The meaning of these departures from the simple 
obliquely-cut thickened end of the style in Violets is 
seen if again we imitate an insect’s visit by 
means of the flower and bristle... The opening 
to the spur is so restricted by a fleshy growth 
from each of the intermediate petals that the 
only way to the honey is beneath the skull- ,f 
like stigma. If the insect’s proboscis has \ 
already been dipped into a Pansy spur and has 
come away with pollen attached, that pollen 
will now be scraped off by the sensitive lip of 
the stigma. On the other hand, to make as certain as 
evidence can testify that this is an arrangement to 
favour cross-fertilisation and prohibit self-fertilisation, 
when a bee’s tongue has got dusted with pollen inside 
this spur and is withdrawn, the sight pressure effect- 
ually shuts up the lip and closes the sensitive cavity 
against its own pollen. These flowers do produce plenty 
of seeds, so there 1s no necessity for cleistogamous 
flowers in this species. But there is a varietal form 
or sub-species with petals usually shorter than the 
sepals or wanting altogether, and the stigmatic cavity 
more to the le of ae “skull,” and without the lip. 
Pollen-grains fall spontaneously out of the anther 
cavity fefore or just after the opening of the flower 
and into the unprotected cavity. Miiller, who first 
called attention to this remarkable contrast in the 
two forms, says :— 
“ When the visits of insects are prevented by a fine 
net, the flowers of the small-flowered form wither two 
Section of 
Pansy Ovary 
