Twenty-three spontaneously self-fertilised capsules from this
form contained, on an average, 19.2 seeds. The short-styled plants produced
fewer spontaneously self-fertilised capsules, and fourteen of them contained
only 6.2 seeds per capsule. The self-fertilisation of both forms was probably
aided by Thrips, which abounded within the flowers; but these minute insects
could not have placed nearly sufficient pollen on the stigmas, as the
spontaneously self-fertilised capsules contained much fewer seeds, on an
average, than those (as may be seen in Table 1.9.) which were artificially
fertilised with their own-form pollen. But this difference may perhaps be
attributed in part to the flowers in the table having been fertilised with
pollen from a distinct plant belonging to the same form; whilst those which were
spontaneously self-fertilised no doubt generally received their own pollen. In a
future part of this volume some observations will be given on the fertility of a
red-coloured variety of the primrose.
Primula Sinensis.
In the long-styled form the pistil is about twice as long as that of the short-
styled, and the stamens differ in a corresponding, but reversed, manner. The
stigma is considerably more elongated and rougher than that of the short-styled,
which is smooth and almost spherical, being somewhat depressed on the summit;
but the stigma varies much in all its characters, the result, probably, of
cultivation.
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