RECAPITULATION. 99 



tion of the great God, who works with means so simple 

 and apparently so weak for so great accomplishments, 

 making the very existence of the gigantic oak, that braves 

 the tempests of a thousand years, the result of the life and 

 labors of the lowly cryptogams. 



CHAPTER XIII. 



SeCTIOK I. — RECAPITULATIOif. 



Having now completed so much of the study of vege- 

 table physiology as the limited plan of this introductory 

 work Avill admit, for the sake of impressing several divis- 

 ions of the subject upon your mind, I will now make a 

 brief recapitulation of the whole. "We first took up the 

 root and its three divisions, ground-roots, air -roots, water- 

 roots, and found these again divided into branching, 

 fibrous, bulbous, tuberous, running, and fusiform ; and 

 that these were either annual, biennial, or perennial. 



From the roots springs the stem. It is either ligneous, 

 hard, woody, and perennial ; herbaceous, succulent, green, 

 and annual; sufi'ruticose, partly woody and partly herb- 

 aceous. Ligneous stems are subdivided into endogenous, 

 inward growth ; exogenous, outward growth ; acrogenous, 

 growing from the apex only. 



At regular intervals upon the branches are nodes ; the 

 spaces between are internodes. From the nodes spring 

 the leaf. The leaf consists of two parts, lamina and petiole. 

 The first leaves are called seminal, the next primordial. 

 Those on the perfect stem, characteristic. When the leaf 

 springs from the root, it is radical ; from the stem, cauline ; 

 when on the stem, sessile. If the leaf falls off early after 

 unfolding, it is caducous; if in autumn, it is deciduous; 

 remaining all winter, persistent or evergreen. 



