IIG 



LETTERS ON TREES. 



the liber ^ occupies tlie chief place, as representing the 

 annual in the yearly sucs^ession of individuals, the 

 buds are the parts w iich in that respect have the 

 chief regard in mine — following herein as I do the 

 teaching of M. Du Tetit-Thouars. In every other 

 respect, M. Mirbel's /iews and mine completely coin- 

 cide. Nay, in as fai as we differ, or rather as he and 

 M. Du Petit-Thou? s differ, it will not, 1 think, be 

 difficult to shew, as I shall endeavour to Jo m my 

 next letter, that there is an intermediate view, which 

 will include and harmonise the views of both these emi- 

 nent physiologists, and more truly than either of them 

 express mine. 



14. There is yet another author whose views I 

 wish to place before you — I mean M. Gaudichaud.f 

 I extract the account given of them by Professor 

 Balfour of Edinburgh, in his Class-Book of Botany 

 (pp. 442-444; :— 



A Monocotyledon (Endogen), in its simplest fovn (Fig. 11), 

 may be said to consist of an axis producing a leaf (c d)^ and 

 a bud (e) at its upper part, and a root (a) below, it may 

 be represented as a phyton, or single plant or bad. havixig an 

 axis or axial merithal, with a leaf or foliar merithai ( .i), 

 divided into a laminar (d) and petiolary portion (r). the latter 

 usually sheathing the axis, and a radicular merithal (a), 



* M. Mirbel subsequently saw reason to substitute the Cambium 

 for the liber. 



t Reciierches sur I'Organographie la Physiologie at I'Organo- 

 genie do3 Vegetaux, 1841. 



