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.
All transitions are found between such forms and typical tracheids.
By a natural series of transitions the gift theory became transformed, in the minds of the sacrificers, into the homage theory, which again passed by an easy transition into the renunciation theory.
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.
From these we can pass by gradual transitions in two directions, viz.