[Narrative of a Survey of the Intertropical and Western Coasts of Australia] [Volume 2 of 2] by Phillip Parker King]@TWC D-Link bookNarrative of a Survey of the Intertropical and Western Coasts of Australia] [Volume 2 of 2] CHAPTER 5 468/583
I had observed also, that the inner coat had no connexion either with the outer or with the nucleus, except at its origin; and that with relation to the outer coat it was generally inverted, while it always agreed in direction with the nucleus.
And, lastly, that at the apex of the nucleus the radicle of the future Embryo would constantly be found. (*Footnote.
Linnean Society Transactions 10 page 35.) On these grounds my opinion respecting the Embryo of Cephalotus was formed.
In describing the Ovulum in this genus, I employed, indeed, the less correct term sacculus, which, however, sufficiently expressed the appearance of the included body in the specimens examined, and served to denote my uncertainty in this case as to the presence of the inner membrane. I was at that time also aware of the existence, in several plants, of a foramen in the coats of the Ovulum, always distinct from, and in some cases diametrically opposite to the external umbilicus, and which I had in no instance found cohering either directly with the parietes of the Ovarium, or with any process derived from them.
But, as I was then unable to detect this foramen in many of the plants which I had examined, I did not attach sufficient importance to it; and in judging of the direction of the Embryo, entirely depended on ascertaining the apex of the nucleus, either directly by dissection, or indirectly from the vascular cord of the outer membrane: the termination of this cord affording a sure indication of the origin of the inner membrane, and consequently of the base of the nucleus, the position of whose apex is therefore readily determined. In this state of my knowledge the subject was taken up in 1818, by my lamented friend the late Mr.Thomas Smith, who, eminently qualified for an investigation where minute accuracy and great experience in microscopical observation were necessary, succeeded in ascertaining the very general existence of the foramen in the membranes of the Ovulum.
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