page_title: Macroneuropteris
section_title: Ovules/seeds
hierarchical_section_title: Macroneuropteris / Reproduction / Ovules/seeds
caption_attribution_description: Trigonocarpus, a fossil seed. From the Sedgwick Museum's collection.
context_page_description: Macroneuropteris is a genus of Carboniferous seed plants in the order Medullosales. The genus is best known for the species Macroneuropteris scheuchzeri, a medium-size tree that was common throughout the late Carboniferous Euramerica. Three similar species, M. macrophylla, M. britannica and M. subauriculata are also included in the genus.
context_section_description: In 1938, W. A. Bell studied the Sydney Coalfield in Nova Scotia, and suggested that the large fossilized seeds called Trigonocarpus noeggerati could be the ovules of Macroneuropteris scheuchzeri. Erwin Zodrow in 2002 also noted that this ovule fossil was commonly in physical association with M. scheuchzeri foliage. Specimens of Trigonocarpus can be quite large. The largest recorded was 10 cm and has been noted as the largest ovule produced by a non-angiosperm seed-plant. Some have noted that the large size of these seeds may have allowed them to float, like small coconuts, to be distributed in these coastal mangrove-like areas as well as inland wetland forests. Their three-part symmetry gives them their name. A tube-like opening at the top brought pollen into the ovule. Pachytesta is a term that is also used for this type of seed/ovule.
caption: Trigonocarpus, the seed/ovule of Medullosales such as Macroneuropteris
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