The plants have woody, columnar, unbranched stems with a crown of large, pinnately compound leaves, which make it look like a palm tree. Mucilage canals are present in the pith and cortex, and the wood is of manoxylic type. The leaf trace is diploxylic. The plants are dioecious, the male and female cones are mostly terminal. The megasporophyll has two to eight large orthotropous ovules. The microsporophylls have microsporangia on the abaxial surface. The motile male gamete (spermatozoid) has a spiral band of flagella.
KeywordsPollen Tube Female Gametophyte Male Gametophyte Leaf Trace Neck Cell
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