Sphenophyta have aerial stems which are hollow and jointed, surrounded by vascular tissue. They evolved to have stems specialized for reproduction, each bearing a conelike strobilus [Solomon et. al. 1996]. This produces a tremendous amount of spores, giving them an edge over the competition. The gametophyte is photosynthetic and independent of the sporophyte and fungi, making it more advanced than previous divisions. These are closely related to Pterophyta, but the relationship is vague at best.

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