This view is even still more tempting in the case of the long-styled
form of Linum grandiflorum. On the other hand, with Pulmonaria angustifolia, it
is evident, from the corolla projecting obliquely upwards, that pollen is much
more likely to fall on, or to be carried by insects down to the stigma of the
short-styled than of the long-styled flowers; yet the short-styled instead of
being more sterile, as a protection against self-fertilisation, are far more
fertile than the long-styled, when both are illegitimately fertilised.
Pulmonaria azurea, according to Hildebrand, is not heterostyled. (3/12. 'Die
Geschlechter-Vertheilung bei den Pflanzen' 1867 page 37.)
[From an examination of dried flowers of Amsinckia spectabilis, sent me by
Professor Asa Gray, I formerly thought that this plant, a member of the
Boragineae, was heterostyled. The pistil varies to an extraordinary degree in
length, being in some specimens twice as long as in others, and the point of
insertion of the stamens likewise varies. But on raising many plants from seed,
I soon became convinced that the whole case was one of mere variability. The
first-formed flowers are apt to have stamens somewhat arrested in development,
with very little pollen in their anthers; and in such flowers the stigma
projects above the anthers, whilst generally it stands below and sometimes on a
level with them.
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