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Wallace, Alfred Russel, 1823-1913

"Darwinism (1889)"

' And he subsequently shows that, in
Xanthoxylum monogynum, 'it often happens that on the same plant, on the
same panicle, we find flowers with one or with two ovaries;' and that
this is an important character is shown by the Rutaceae (to which
Xanthoxylum belongs), being placed in a group of natural orders
characterised by having a solitary ovary."
"De Candolle has divided the Cruciferae into five sub-orders in
accordance with the position of the radicle and cotyledons, yet Mons. T.
Gay (_Ann. des Scien. Nat._, ser. i. tom. vii. p. 389) found in sixteen
seeds of Petrocallis Pyrenaica the form of the embryo so uncertain that
he could not tell whether it ought to be placed in the sub-orders
'Pleurorhizee' or 'Notor-hizee'; so again (p. 400) in Cochlearia
saxatilis M. Gay examined twenty-nine embryos, and of these sixteen were
vigorously 'pleurorhizees,' nine had characters intermediate between
pleuro-and notor-hizees, and four were pure notor-hizees."
"M. Raspail asserts (_Ann. des Scien. Nat._, ser. i. tom. v. p. 440)
that a grass (Nostus Borbonicus) is so eminently variable in its floral
organisation, that the varieties might serve to make a family with
sufficiently numerous genera and tribes--a remark which shows that
important organs must be here variable.


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