694 



THE WONDERS OF GEOLOGY. Lect. VII. 



we must now call to our aid that branch of science which 

 treats of vegetable organization ; we shall thus be enabled 

 to restore anew the forests of extinct palms and tree-ferns, 

 the groves of coniferae, and all the luxuriant vegetation 

 which flourished during the carboniferous epoch. I must, 

 however, restrict myself to a brief enunciation of a few 

 leading botanical principles.* The works of M. Adolphe 

 Brongniart,f and of Messrs. Lindley and Hutton,J should 

 be consulted by those who would pursue this attractive 

 department of natural history. § 



22. Organization of Vegetables. — In the previous 

 discourse, the complex organization of the higher orders of 

 animal existence was remarked ; the structure of vegetables, 

 on the contrary, presents a remarkable simplicity. While 

 in most animals each separate function is effected by an 

 organ of peculiar construction, in plants a few tissues, 

 variously modified, constitute the mechanism by which all 

 the vegetable functions are performed. The section of any 

 living plant shows that its intimate structure is made up of 

 cells or vessels. || This organization is differently arranged 

 in the grand classes of the vegetable kingdom. In the most 



* I have still further abridged this article in the present edition, 

 having fully entered upon the subject in my Medals of Creation, 

 vol. i. chap. 4. 



f Histoire des Vegetaux Fossiles, ou Recherches Botaniques et 

 G6ologiques, &c. par M. Adolphe Brongniart. 1 vol. 4 to. with nume- 

 rous plates. 



X The Fossil Flora of Great Britain, by Dr. Lindley and W. 

 Hutton, Esq. 8vo. 



§ See also Henslow's Principles of Physiological Botany; a very 

 instructive and delightful volume. 



|| Every vegetable cell is the result of the development of a minute 

 granular body, on the surface of which a transparent vesicle arises, and 

 spreads out so as to form a cell, which afterwards expanding more 

 in particular parts, acquires the peculiar form which characterizes 

 the texture to be fabricated. The chemical composition of this 

 elementary structure is identical with starch. In every vegetable, 

 whether the oak or the fungus, this primitive membrane presents the 



