350 VIF,WS, &C. PHYSIOGNOMY OF PLANTS. 



the incessant effort to arrive at a generalisation of ideas sup- 

 ported by individual illustrations, is associated with an endea- 

 vour to penetrate to the specialities of phenomena. 



The enumeration of forms is, from the physiognomical differ- 

 ence of their nature, incapable of any strict classification. 

 Here, as everywhere in the consideration of external forms, 

 there are certain main types which present the strongest con- 

 trasts, as the groups of the Arborescent Grasses, the Aloe 

 form and the species of Cactus, Palms, Acicular-leaved trees, 

 Mimosacese, and Bananas. Even scantily dispersed individuals 

 belonging to these groups determine the character of a district, 

 and produce a lasting impression on the mind of the unscien- 

 tific but susceptible beholder. Other forms, perhaps more 

 numerous and preponderating, may not appear equally marked 

 either by the shape or position of the leaves ; the relation of 

 the stem to the branches, luxuriant vigour, animation, and 

 grace; or even by the melancholy contraction of the leaf- organs. 



As, therefore, a physiognomical classification, or a distribu- 

 tion into groups according to external appearance, does not 

 admit of being applied to the whole vegetable kingdom col- 

 lectively, the basis on which such a classification should be 

 grounded must necessarily be wholly different from that which 

 has been so happily chosen for the establishment of our com- 

 prehensive systems of the natural families of plants. Vege- 

 table physiognomy grounds its divisions and the choice of its 

 types on all that possesses mass, as the stem, branches, and 

 appendicular organs (the form, position, and size of the leaf, 

 the character and brilliancy of the parenchyma), and conse- 

 quently on all that is now included under the special term, i'ne 

 organs of vegetation, and on which depend the preservation 

 (nourishment and development) of the individual ; while sys- 

 tematic botany, on the other hand, bases the arrangement of 

 the natural families of plants on a consideration of the organs 

 of propagation, on which depends the preservation of the 

 species.* It was already taught in the school of Aristotle,f 

 that the generation of seed is the ultimate aim of the being 

 and life of a plant. The process of development in the organs 

 of fructification has become, since Caspar Fried. Wolf,J and 



* Kimth, Lelirbuch der Botanik, 1847. Th. i. s. 511; Schleiden, 

 Die Pflanze und ihr Leben, 1848, s. 100, 

 f Probl. 20, 7. 

 J Theoria Generationis, 5 9. 



