Sentence Examples


  • Heterospory is only known in the Hydropterideae.
  • In several cases heterospory, unknown among recent Equisetaceae, has been demonstrated in their Palaeozoic representatives.
  • In most other respects the two genera agree; there is evidence for the occurrence of heterospory in some strobili referred to Palaeostachya.
  • The spores of this genus are curiously winged, and intermediate in size between the microspores and megaspores of Lepidostrobus; the question of homospory or heterospory is not yet decided.
  • Each sporangium had, on one side only, a longitudinal or slightly oblique annulus, several cells in width; the numerous spores were all of the same size; certain differences among them, which have been interpreted as indicating heterospory, have now proved to depend merely on the state of preservation.