Page:An introduction to physiological and systematical botany (1st edition).djvu/323

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OR YOLK.
293

and Garden Nasturtium are, as he seems to indicate in his Introduction, p. 151, rather of the nature of a Vitellus. It does not appear that any plant with genuine ascending Cotyledons is likewise furnished with this organ; on the other hand, it commonly belongs to such as have the most copious Albumen, and therefore should seem to answer some other end than mere nutriment, which is supplied by the latter.

We learn from the above inquiries, that the old distinction between plants with one Cotyledon and those with several may still be relied on, though in the former the part which has commonly been so denominated is the Albumen, as in Corn, the real Cotyledon of which is the scale or Vitellus, which last organ however seems wanting in Palms, Lilies, &c., such having really no Cotyledon at all, nor any thing that can perform its office, except the stalk of their Embryo[1]. In the Horse Chesnut, Oak and Walnut possibly, whose seed-lobes

  1. This may answer the purpose of a Cotyledon, just as the stems of many plants fulfil the office of leaves.