A fossil plant which is intermediate between the ferns and seed-bearing plants, dying out in the Triassic period. Also called seed fern.
Más ejemplos en oraciones
- The idea that cycads stem from Carboniferous so-called pteridosperms (‘seed ferns’ or seed plants with fern-like foliage) has long been popular with paleobotanists.
- The Pteridopsida were present, bearing spores on their leaves as they do today, but there were also fernlike seed-bearing ferns, the pteridosperms.
- The first seeds evolved in a group of vascular plants sometimes called the pteridosperms, or ‘seed ferns.’
Definición de pteridosperm en:
- el diccionario Inglés de EE.UU.