All the flowers in a large bed of Stachys
coccinea had either one or two slits made on the upper side of the
corolla near the base. The flowers of a Mirabilis and of Salvia coccinea
were perforated in the same manner; whilst those of Salvia grahami, in
which the calyx is much elongated, had both the calyx and the corolla
invariably perforated. The flowers of Pentstemon argutus are broader
than those of the plants just named, and two holes alongside each other
had here always been made just above the calyx. In these several cases
the perforations were on the upper side, but in Antirrhinum majus one or
two holes had been made on the lower side, close to the little
protuberance which represents the nectary, and therefore directly in
front of and close to the spot where the nectar is secreted.
But the most remarkable case of skill and judgment known to me, is that
of the perforation of the flowers of Lathyrus sylvestris, as described
by my son Francis. (11/15. 'Nature' January 8, 1874 page 189.) The
nectar in this plant is enclosed within a tube, formed by the united
stamens, which surround the pistil so closely that a bee is forced to
insert its proboscis outside the tube; but two natural rounded passages
or orifices are left in the tube near the base, in order that the nectar
may be reached by the bees. Now my son found in sixteen out of
twenty-four flowers on this plant, and in eleven out of sixteen of those
on the cultivated everlasting pea, which is either a variety of the same
species or a closely allied one, that the left passage was larger than
the right one.
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