Page:Miscellaneousbot01brow.djvu/513

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IN ORCHIDEÆ AND ASCLEPIADEÆ
495

rous ramuli, which spread themselves among the ovula, and separate them into irregular groups.

Hence, according to this author, a communication is established between the anthera and the ovula, which he adds are impregnated through their surface, and not, as he supposes to be the case in other families, through their funiculus or attachment to the placenta.

The remarkable account of the stigma here quoted, though coming from so distinguished and original an observer, and one who had particularly studied this family of plants, seems either to have been entirely overlooked, or in some degree discredited by more recent writers, none of whom, as far as I can find, have even alluded to it. And I confess it entirely escaped me until after I had made the observations which will be stated in the present essay, and which confirm its accuracy as to the existence and course of the parietal cords, though not as to their nature and origin.

In 1824 Professor Link[1] expresses his opinion that the rostellum of Richard is without doubt the true stigma.

In 1829 Mr. Lindley,[2] who for several years has particularly studied and has lately published part of a valuable systematic work on Orchideous Plants, states that in this family impregnation takes effect by absorption from the pollen masses through their gland into the stigmatic channel.

In 1830, in his Introduction to the Natural System of Botany, the same statement is repeated; and in this [692 work it also appears that he regards the glands to which the pollen masses become attached in Ophrydeæ as derived from the stamen, and not belonging to the stigma,[3] as in 1810 I had described them. It would even appear, from a passage in his systematic work[4] published in the same

  1. Philos. Bot. p. 298.
  2. Synops. Brit. Flor. p. 256.
  3. "The pollen is not less curious. Now we have it in separate grains, as in other plants, but cohering to a mesh-work of cellular tissue, which is collected into a sort of central elastic strap; now the granules cohere in small angular indefinite masses, and the central elastic strap becomes more apparent, has a glandular extremity, which is often reclined in a peculiar pouch especially destined for its protection."—Introduct. to Nat. Syst. of Bot. p. 263.
  4. Gen. and Sp. of Orchid. Part I, p. 3.