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IN ORCHIDEÆ AND ASCLEPIACEÆ.
493

denominates that part, before the pollen masses are [689 attached to it, "stigma virgineum" it may be considered as belonging to the same class.

Koelreuter, the next writer in point of time, and whose essay was published before Linnæus's query appeared, states, in 1775,[1] that the pollen masses, which he denominates naked antheræ, impart their fecundating matter to the surface of the cells of the true anthera, regarded by him consequently as stigma, and that through this surface it is absorbed and conveyed to the ovarium.

In 1787, Dr. Jonathan Stokes[2] conjectures that in Orchideæ, as well as in Asclepiadeæ, the male influence, or principle of arrangement, as it is termed by John Hunter, may be conveyed to the embryo without the intervention of air: a repetition certainly of Linnicus's conjecture, with which, however, as it was not published till 1791, he could not have been acquainted.

In 1791, Batsch[3] states that in Orchis and Ophrys,—and his observation may be extended at least to all Satyrinæ or Ophrydeæ,—the only way in which the mass of pollen can act on the ovarium, is by the retrogradation of the impregnating power through the pedunculus or caudicula of the pollen mass to the gland beneath it, which he is disposed to refer rather to the stigma than to the anthera.

The late Professor Richard, in 1802,[4] expressly says that fecundation is operated in Orchideæ and Asclepiadeæ without a change of place in the stamina; his opinion therefore must be considered identical with that of Batsch, and extended to the whole order.

It might perhaps be inferred from the description which I gave of Orchideæ in a work publislied in 1810,[5] that my opinion respecting the mode of impregnation agreed with [690 that of Batsch and Richard, though it is not there actually expressed, nor indeed very clearly in another publication of nearly the same date,[6] in which I had adverted to this

  1. Act. Phys. Palat. iii, p. 55.
  2. With. Bot. Arrang. 2nd ed. ii, p. 964.
  3. Botanische Bemerk. i, p. 3.
  4. Dict. de Botan. par Bulliard, ed. 2. p. 56.
  5. Prodr. Flor. Nov. Holl. i, p. 310.
  6. Linn. Soc. Transact. x., p. 19.