Arborescent Pteridophytes are barely represented, and such dominant types as Lepidodendron, Sigillaria, Calamites and Sphenophyllum have practically ceased to exist; Cycads and Conifers have assumed the leading role, and the still luxuriant fern vegetation has put on a different aspect.
Watson further brought out the striking fact that the west and east of Britain each had species peculiar to it; the former he characterized as Atlantic, the latter as Germanic. The Cornish heath (Erica vagans) and the maiden-hair fern (Adiantum CapillusVeneris) may serve as instances of the one, the man-orchis (Aceras anthropophora) and Reseda lutea of the other.
Others have hollow or funnel-shaped ends and are constricted at the middle like a dice cup. In some rocks small rod-like microlites are grouped together in a regular way to form growths which resemble fir branches, fern leaves, brushes or networks, in the same manner as minute needles of ice produce star-like snow crystals or the frost growths on a window pane.
The natives are in the habit of making holes in the aa, and planting in them banana shoots or sweet-potato cuttings, and though the holes are simply filled with stones or fern leaves, the plants grow and in due time are productive.
Polycycly was derived independently from monocycly in solenostelic and in dictyostelic forms. In the formation of the stem of any fern characterized in the adult condition by one of the more advanced types of vascular structure all stages of increase in complexity from the haplostele of the first-formed stem to the particular condition characteristic of the adult stem are gradually passed through by a series of changes exactly parallel with those which we are led to suppose, from the evidence obtained by a comparison of the adult forms, must have taken place in the evolution of the race, There is no more striking case in the plantkingdom of the parallel between ontogeny (development of the individual) and phylogeny (development of the race) so well known in many groups of animals.
This Jurassic species bore bipinnate fronds not unlike those of the South African, Australian, and New Zealand Fern Todea barbara, which were characterized by a stout rachis and short broad pinnules bearing numerous large sporangia covering the under surface of the lamina.
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.
Many visitors came to Fern Quarry.
Paradoxa of South Africa), the long and comparatively broad pinnae, with an entire or irregularly incised margin, are very fern-like, a circumstance which led Kunze to describe the plant in 1835 as a species of the fern Lomaria.
As the result of fertilization of an ovum produced by this, the fern plant (sporophyte, asexual generation) originates; from it spores are ultimately set free,.