Usage
  • 22 views
  • 208 downloads

Seeds and Embryos of Araucaria mirabilis.

  • Author(s) / Creator(s)
  • Seeds and embryos contained within the silicified ovuliferous cone Araucaria mirabilis from the Cerro Cuadrado petrified forest are described. One wingless seed, 0.8-1.3 cm in length and 0.2-0.6 cm in width, is embedded in each ovuliferous scale. Seeds show a three-layered integument and a prominent wavy nucellus which is attached basally to the endotesta. The megagametophyte contains cellular inclusions that may represent starch grains. Ovule vascu- larization is complex and appears most similar to that of Araucaria bidwillii. Embryos 2 mm long and 0.25 mm wide appear to be in a telo-stage period of development. Shoot apex, cot- yledons, root meristem, and calyptroperiblem are present in the embryos in which vascular tissues and secretory elements were beginning to differentiate at the time of fossilization. Embryo ontogeny is considered in light of stages encountered in extant gynmosperm taxa. The absence of the microgametophyte phase in the Cerro Cuadrado collection is discussed.

  • Date created
    1975
  • Subjects / Keywords
  • Type of Item
    Article (Published)
  • DOI
    https://doi.org/10.7939/R3GH9BM2Z
  • License
    This version of this article is open access and can be downloaded and shared. The original author(s) and source must be cited.
  • Language
  • Citation for previous publication
    • Stockey, R.A. (1975). Seeds and Embryos of Araucaria mirabilis. American Journal of Botany , Vol. 62, No. 8, 856-868