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Elsewhere on the web
The chalaza, properly so called, though merely the termination of the raphe, affords a less certain character, for in many plants it is hardly visible on the inner surface of the testa, but is intimately united with the areola of insertion of the inner membrane or of the nucleus, to one or other of which it then seems entirely to belong.— Narrative of a Survey of the Intertropical and Western Coasts of Australia Performed between the years 1818 and 1822 — Volume 2
If you are very picky, you will want to remove the chalaza.— Latest Articles
The chalaza is composed of one or two spiral bands of tissue that suspend the yolk in the center of the white.— Latest Articles
The entrance of pollen-tubes into the nucellus by the chalaza, instead of through the micropyle, was first fully demonstrated by Treub in his paper "Sur les— More Letters of Charles Darwin — Volume 2
But here is an odd thing: they never once enter at (what I suppose to be) the "orifice," but generally at the chalaza ...— More Letters of Charles Darwin — Volume 2

American Heritage Dictionary (1)
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