The first exponent of the theory of sudden appearance of new parts and new types, to our knowledge, was Geoffroy St Hilaire, who suggested saltatory evolution through the direct action of the environment on development, as explaining the abrupt transitions in the Mesozoic Crocodilia and the origin of the birds from the reptiles.
The second half of the 17th century witnessed remarkable transitions and developments in all branches of natural science,and the facts accumulated by preceding generations during their generally unordered researches were re placed by a co-ordination of experiment and deduction.
The fibres belong to the same n,orpholcgical category as the parenchyma, various transitions being found between them; thus there may be thin-walled cells of the shape of fibres, or ordinary fibres may be divided into a number of superposed cells.
It appals the reader with its irregularity of treatment, its variations of style, and its abrupt transitions from the spiritual to the crude and trivial, and from superstition to the purest insight.
In the numberless transitions that, whilst connecting, separate the spell and the prayer we observe as the accompaniment of every mood from extreme imperiousness to extreme humility an abiding will and desire to help the action out.
The seeds brought home by Banks in 1771 did not succeed, but the plant was introduced by him to the Royal Gardens at Kew in 1789, and was thence liberally distributed in the ground-mass, and these rocks form transitions to the nephelinites (nephelinitoid phonolites) (see Petrology, Plate III.
At this a sudden change evidently took place in the princess' ideas; her thin lips grew white, though her eyes did not change, and her voice when she began to speak passed through such transitions as she herself evidently did not expect.
The sexual reproduction shows all transitions between forms which are normally sexual, like the Peronosporaceae, to forms in which no antheridium is developed and the oospheres develop parthenogenetically.
The art of both stories is great, and that of the episode of the daughter Susannah in Roxana is consummate; but the transitions of the later plot are less natural than those in Moll Flanders.
The formation of clans and tribes, the transitions from the hunting to the pastoral life, and from the pastoral to the agricultural - the struggle with forest and swamp, the clearings for settlement, the protection of the dwelling-place, the safety of flocks and herds, the production of corn, - the migration of peoples, the founding of colonies, the processes of conquest, fusion, and political union - have all reacted on the elaboration of the higher polytheisms, before bards and poets, priesthoods and theological speculators, began to systematize and regulate the relations of the gods.