Williamsoniaceae
Williamsoniaceae is a family within the Bennettitales, an extinct group of seed plants within the Cycadophyta subdivision. Members of this family are believed to have been around two meters tall and with widely serrate leaves along a central stem. Reproductive organs of the Williamsoniaceae have varied widely in the fossil record but almost all have been found to be borne on stalks emerging from a ring of leaves.[1]
| Williamsoniaceae | |
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| Ptilophyllum sp., a member of the Williamsoniaceae | |
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| Family: | Williamsoniaceae |
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Reproduction
This family is different from Cycadeoidaceae by having the presence of cones leaving the major axis and lateral branches associated with a long peduncle covered by bracts. Some of this family reproduce by sporangia and others only produce ovule or pollen sacs.[2]
gollark: I'd kind of expect other people to have noticed and reported this if it is actually a general problem with these versions, since I'm using calibre and qt from the repos.
gollark: I tried downgrading it from 5.14.2 to 5.14.1 or something, but that didn't do anything, and I probably can't downgrade further without just reverting all my package versions to a week or so ago, which is not ideal.
gollark: Anyone know why the Qt-using applications (deepin-screenshot, multiMC, calibre) on my laptop recently started segfaulting after I updated my system?
gollark: There *are* already non-docker container tools.
gollark: It's running Arch Linux, the most stablest OS.
References
- Meyen, Sergei V. (1984). "Basic Features of Gymnosperm Systematics and Phylogeny as Evidenced by the Fossil Record". Botanical Review. 50 (1): 1–111. doi:10.1007/BF02874305. JSTOR 4354028.
- Paleontologia Paleovertebrados e Paleobotânica Autor : Ismar de Souza Carvalho. Editora Interciência.
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