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Darwin, Charles, 1809-1882

"The Different Forms of Flowers on Plants of the Same Species"

Plantago media does not present two forms; but it
appears from Asa Gray's description, that such is the case with four of the
North American species. (7/21. 'Manual of the Botany of the Northern United
States' 2nd edition 1856 page 269. See also 'American Journal of Science'
November 1862 page 419 and 'Proceedings of the American Academy of Science'
October 14, 1862 page 53.) The corolla does not properly expand in the short-
stamened form of these plants.
Cnicus, Serratula, Eriophorum.
In the Compositae, Cnicus palustris and acaulis are said by Sir J.E. Smith to
exist as hermaphrodites and females, the former being the more frequent. With
Serratula tinctoria a regular gradation may be followed from the hermaphrodite
to the female form; in one of the latter plants the stamens were so tall that
the anthers embraced the style as in the hermaphrodites, but they contained only
a few grains of pollen, and these in an aborted condition; in another female, on
the other hand, the anthers were much more reduced in size than is usual.
Lastly, Dr. Dickie has shown that with Eriophorum angustifolium (Cyperaceae)
hermaphrodite and female forms exist in Scotland and the Arctic regions, both of
which yield seed. (7/22. Sir J.E. Smith 'Transactions of the Linnean Society'
volume 13 page 599. Dr. Dickie 'Journal of the Linnean Society Botany' volume 9
1865 page 161.


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