: an order of fossil gymnospermous plants first known from the Carboniferous and probably becoming extinct during the Cretaceous that appear to have derived from the seed ferns but have megasporophylls aggregated into cones and with little resemblance to foliage leaves, that are in general structurally similar to the cycads from which they differ chiefly in having the reproductive organs on the trunk embedded in a thick external covering of persistent leaf bases, and that have been considered as possible ancestors of the angiosperms see bennettitaceae
Word History
Etymology
New Latin, from Bennettites + -ales
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