132 GROWTH. 



first by the union of the bases of the leaves, bundles of 

 fibres are generated ; more bundles continuing to be 

 formed, then push away those formed before them, and 

 gradually press them towards the circumference, this 

 central generation, and pressure towards the circumfe- 

 rence going on, causes the latter to become so hard, 

 that at last it will not yield to any more pressure ; 

 increase of diameter therefore ceases, though that of 

 length continues : and thus from the stem growing from 

 within, the new matter pushing the old outwards, it 

 receives its name of Endogenous. 



213. It is now satisfactorily proved, however, that the 

 manner of growth is somewhat different from that men- 

 tioned above, and the term Endogenous is not so appli- 

 cable as was formerly supposed. 



214. The younger Moldenhauer, several years after 

 the announcement of the views of Des Fontaines, which 

 took place in 1796, stated, that the woody fibres proceed- 

 ing from the bases of Palm leaves, dived so much more 

 towards the centre of the stem, the older the leaves were, 

 so that the inner bundles of wood were to be looked 

 upon as belonging to the oldest leaves, just the reverse 

 of the theory of Des Fontaines. Latterly the researches 

 of Mohl upon Palm trees, brought to Europe by Mar- 

 tius, and those of Decandolle, Meyen, and others, have 

 proved, that the youngest formed bundles of woody 

 matter lie in the centre of the stem at first, but as they 

 run down it diverge to its circumference, so that the 

 bundles do not lie parellel with each other, but that 

 there is a continual crossing of the inner over the outer 

 ones ; and that, therefore, from observations upon 

 woody Endogens, the following seems to be their mode 

 of growth. 



215. The new leaves at the top of the stem develop 

 fibrous roots or woody bundles, which pierce down- 

 wards along the axis towards the centre, in which they 

 continue to run for a certain distance, and then di- 

 verge out towards the circumference, having attained 

 which, they keep running down in a parallel direction 



