Marattiaceous sentence example
- The fructifications by themselves are not necessarily decisive, for in certain cases the supposed sporangia of Marattiaceous Ferns have turned out to be in reality the microsporangia or pollen-sacs of seed-bearing plants (Pteridosperms).
- A considerable number of the Palaeozoic fern-like plants show indications - more or less decisive - of Marattiaceous affinities; some account of this group will first be given.
- Typically Marattiaceous sori, consisting of exannulate sporangia united to form synangia, are frequent, and are almost always found on fronds with the character of Pecopteris, large, repeatedly pinnate leaves, resembling those of Cyatheaceae or some species of Nephrodium.
- The magnificent Devonian Fern Archaeopteris hibernica, with a somewhat Adiantiform habit, bore special fertile pinnae; the fructification is still imperfectly understood, but the presence of stipules, observed by Kidston, has been adduced in support of Marattiaceous affinities.
- On the other hand there was the far more complex Marattiaceous type, strikingly similar in both vegetative and reproductive characters to the recent members of the family.Advertisement
- They are of the type known as Crossotheca, formerly regarded as a Marattiaceous fructification.
- It has now been established that the form-genus Pecopteris, once regarded as representing the typical Marattiaceous foliage, was in part made up of seed-bearing plants.
- There is reason to believe that other species of Pecopteris and similar genera, (Callipteris and Mariopteris) bore seeds, though the artificial group Pecopterideae probably also includes the fronds of true Marattiaceous Ferns.
- " Ferns " and Pteridosperms are even more strongly represented than before, and this is the age in which the supposed Marattiaceous tree-ferns reached their maximum development.
- The abundance of Palaeozoic plants with sporangia and sori of the Marattiaceous type is in striking contrast to the scarcity of Mesozoic ferns which can be reasonably included in the Marattiaceae.Advertisement
- As a similar differentiation, though less marked, appears in the recent genus Angiopteris, the presumption is in favour of the Marattiaceous affinities of Sturiella, which also shows some relation to the genus Corynepteris (see below, Botryopterideae).