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Ch 3

[2 lines illeg]

are fecundated [which] [2 words illeg] pollen farinaceous & flower submerged. – The concave bases of leaves prevent access of water to submerged flowers of Isoetes - In Pilularia & Marsilea Cryptogam subject to occasional inundations, the fecundation is performed in perfectly closed vessels. (Do not their flowers ever flower in air?-) All pollen is not farinaceous as in Apocyneae &c &c.  Plants which are [illeg]

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[many words illeg]

 

[Joseph Correa De Serra. 1796. On the fructification of the submersed algæ. 494-505. Transactions of the Philosophical Society of London, p. 502. "In the Pilularia, and Marsilea, whose flowers are exposed to inundations, the fecundation is performed in perfectly closed vessels. Even in plants living in the air, nature employs numberless well known contrivances, to shelter the farinaceous pollen from the contact of water in rainy seasons. The pollen, to be active in fecundation, needs not always be farinaceous. In most Apocyneae it is rather a fluid; in the Orchideas it is an aggregate of solid parts, of a ceraceous appearance; in some Contortae it is found in a solid or rather viscous state. In the Pilularia, and Marsilea, the particles of the pollen are kept in small bags of a mucous"

p. 503. "substance, compared by Bernard de Jussieu to dissolved gum. The original state in which it is found in every flower, before the act of fecundation, is that of a mucus, but it is perfectly active even in that state, since its particles, after becoming a little dry, if put into certain fluids, are seen, by the help of the microscope, acting in the same manner as when in the state of perfect farina."]