Page:Miscellaneousbot01brow.djvu/591

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OF THE EMBRYOS IN THE SEEDS OF CONIFERÆ.
573

markably modified ; and they have ascertained some points in Pinnus itself that I had overlooked.

In this memoir M. de Mirbel refers to his early observations on the structure of the seeds of Cycas which occur in an essay read before the Academy of Sciences in October 1810, and soon after published in the ' Annales du Muséum.'}[1]

These observations and the figures illustrating them clearly prove M. de Mirbel's knowledge of the plurality of embryos in Cycas at that period. And in his recent memoir on Coniferæ he regards them as giving the earliest notice of that remarkable structure ; stating also that my first publi- cation on the same subject was in 1835.

But as the 'Prodromus Floræ Novæ Hollandiæ)' was published before M. de Mirbel's essay in the 'Annales du Muséum which appears from his references to that work in the essay in question, he must have overlooked the fol- lowing passages : —

"In Cycadi angulata puncta areæ depressæ apicis seminis totidem canalibus brevibus respondent gelatina homogenea primum repletis et membrana propria instructis, unico quantum observavimus embryonifero, quo augente reliqui mox obliterati sunt." — Prodr. p. 347.

"Structura huic omnino similis hactenus absque exemplo nee ulla analoga (nempe embryones plures in distinctis cavitatibus ejusdem albuminis) nisi in Cycadi et noununquam in Visco cognita sit." — Prodr. p. 307.

I may add, that this structure of Cycas was ascertained in living plants on the east and north coasts of New Holland in 1802 and 1803.

The earliest observer of the principal fact, however, was probably the late Aubert du Petit Thouars, who in a dissertation on the structure and affinities of Cycas published in 1804,[2] distinctly notices the Points on the surface and the corresponding corpuscula within the apex of the Albumen, into which corPuscula he hazards the conjecture that the grains [373 of pollen enter and become the future embryos. This, in

  1. Annales du Muséum d'hist. Nat. toM, xvi, p. 252, tab. 20.
  2. Histoire des Végétaux des Iles d'Afrique, p. 9, tab. 2, n.