In the short-styled flowers whether large or small, the stigma is
seated low down within the tube of the corolla. The papillae on the long-styled
stigma are longer than those on the short-styled, in the ratio of 100 to 40. The
filaments in some of the short-styled flowers were, to those of the long-styled,
as 100 to 25 in length, the free, or unattached portion being alone measured;
but this ratio cannot be trusted, owing to the great variability of the stamens.
The mean diameter of eleven pollen-grains from long-styled flowers, and of
twelve from the short-styled, was exactly the same. It follows from these
several statements, that the difference in length and state of surface of the
stigmas in the flowers is the sole reliable evidence that this species is
heterostyled; for it would be rash to trust to the difference in the length of
the pistils, seeing how variable they are. I should have left the case
altogether doubtful, had it not been for the observations on the following
species; and these leave little doubt on my mind that the present plant is truly
heterostyled. Professor Gray informs me that in another species, G.
coronopifolia, belonging to the same section of the genus, he can see no sign of
dimorphism.
Gilia (Leptosiphon) micrantha.
A few flowers sent me from Kew had been somewhat injured, so that I cannot say
anything positively with respect to the position and relative length of the
organs in the two forms.
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