The strobilus is a reproductive structure which is characterized by the presence of a central axis and the spirally arranged sporophylls. Each sporophyll bears a ligule at its base and also possesses a single stalked sporangium. The sporangia are of two types; the microsporangium and mega sporangium. The sporophylls bearing the microsporangium are known as the microsporophyll and that bearing the mega sporangium is known as the mega sporophylls. The microsporophyll and mega sporophyll are found in the same strobilus or different strobilus. When both the sporophylls are found in same strobilus the megasporophyll may be found in the lower portion and microsporophyll in the upper portion of the strobilus.
