Band 6 page 52. Also 'Die Primulaceen-Bastarten' 'Oest. Botanische Zeitschrift'
1835 Numbers 3, 4 and 5.)

This species is heterostyled, like the preceding ones; but amongst the varieties
distributed by florists the long-styled form is rare, as it is not valued. There
is a much greater relative inequality in the length of the pistil and stamens in
the two forms of the auricula than in the cowslip; the pistil in the long-styled
being nearly four times as long as that in the short-styled, in which it is
barely longer than the ovarium. The stigma is nearly of the same shape in both
forms, but is rougher in the long-styled, though the difference is not so great
as between the two forms of the cowslip. In the long-styled plants the stamens
are very short, rising but little above the ovarium. The pollen-grains of these
short stamens, when distended with water, were barely 5/6000 of an inch in
diameter, whereas those from the long stamens of the short-styled plants were
barely 7/6000, showing a relative difference of about 71 to 100. The smaller
grains of the long-styled plant are also much more transparent, and before
distention with water more triangular in outline than those of the other form.
Mr. Scott compared ten plants of both forms growing under similar conditions,
and found that, although the long-styled plant produced more umbels and more
capsules than the short-styled, yet they yielded fewer seeds, in the ratio of 66
to 100. (1/12. 'Journal of the Linnean Society Botany' volume 8 1864 page 86.)
Three short-styled plants were protected by me from the access of insects, and
they did not produce a single seed. Mr. Scott protected six plants of both
forms, and found them excessively sterile. The pistil of the long-styled form
stands so high above the anthers, that it is scarcely possible that pollen
should reach the stigma without some aid; and one of Mr. Scott's long-styled
plants which yielded a few seeds (only 18 in number) was infested by aphides,
and he does not doubt that these had imperfectly fertilised it.

I tried a few experiments by reciprocally fertilising the two forms in the same