Amphibia appeared before its close, and plant life was abundant and varied, though the types were not greatly in advance of those of the Devonian.
Huxley questioned the time value of fossils, but recent research has tended to show that identity of species and of mutations is, on the whole, a guide to synchroneity, though the general range of vertebrate and invertebrate life as well as of plant life is generally necessary for the establishment of approximate synchronism.
We see it exemplified in plant life in circumstances which are unnatural to the life of the plant, and the prevalence of certain constitutional tendencies among the inhabitants of crowded cities bears evidence to the same law.
The spring outburst of plant life in the sea culminates about April, just about the time when the temperature of the water begins to rise rapidly.
This flora, isolated by arid country from the rest of the continent, has evidently derived its plant life from an outside source, probably from lands no longer existing.
Nowhere in California is plant life more varied and beautiful; in the vicinity are walnut, olive, lemon and orange groves.
This wealth of plant life is confined to the littoral and the coastal valleys, but the central valleys and the plateaux have, if not a varied flora, a considerable wealth of timber trees in every way superior to the flora inland in the same latitudes.
Fungi Algae Bryophyta Pteridophyta Phanerogamia Gymnosperms Angiosperms Algae in this wide sense may be briefly described as the aggregate of those simpler forms of plant life usually devoid, like the rest of the Thallophyta, of differentiation into root, stem and leaf; but, unlike other Thallophyta, possessed of a colouring matter;.
The landscape around them was bleak, almost as devoid of plant life as the white sands had been.
These widely divergent conditions give to Mexico a flora that includes the genera and species characteristic of nearly all the zones of plant life on the western continents - the tropical jungle of the humid coastal plains with its rare cabinet-woods, dye-woods, lianas and palms; the semi-tropical and temperate mountain slopes where oak forests are to be found and wheat supplants cotton and sugar-cane; and above these the region of pine forests and pasture lands.