The long-styled pistil is sometimes thrice as long as that of the short-styled;
but from an average of ten measurements of both, its length to that of the
short-styled was as 100 to 56. The stigma varies in being more or less, though
slightly, lobed. The anthers also vary much in length in both forms, but in a
greater degree in the long-styled than in the short-styled-form; many in the
former being from 80 to 63, and in the latter from 80 to 70 divisions of the
micrometer in length. From an average of seven measurements, the short-styled
anthers were to those from the long-styled as 100 to 91 in length. Lastly, the
pollen-grains from the long-styled flowers varied between 13 and 11.5 divisions
of the micrometer, and those from the short-styled between 15 and 13. The
average diameter of 25 grains from the latter, or short-styled form, was to that
of 20 grains from the long-styled as 100 to 91. We see, therefore, that the
pollen-grains from the smaller anthers of the shorter stamens in the long-styled
form are, as usual, of smaller size than those in the other form. But what is
remarkable, a larger proportion of the grains were small, shrivelled, and
worthless. This could be seen by merely comparing the contents of the anthers
from several distinct plants of each form. But in one instance my son found, by
counting, that out of 193 grains from a long-styled flower, 53 were bad, or 27
per cent; whilst out of 265 grains from a short-styled flower only 18 were bad,
or 7 per cent.
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