According to Grand' Eury, the Palaeostachya fructification was most commonly associated with Asterophyllites foliage.
The characters of Sphenophyllum are known with some completeness, while our knowledge of Cheirostrobus confined to the fructification; the former therefore be described first.
The great length and slender proportions of the segments give the cone a peculiar character, but the relations of position appear to leave no doubt as to the homologies with the fructification of Sphenophylleae; as regards the sporangiophores, Bowmanites Romeri occupies exactly the middle place between S.
The fructification consists of long, lax spikes, with whorled sporophylls; indications of megaspores have been detected in the sporangia.
The female fructification is in the form of a rather lax strobilus.