CHAP. 1. THE TRUNK. 43 



dens or root above ground.* Bat without waiting 

 to offer any illustration of this comparison, which 

 is perhaps more fanciful than philosophical, I shall 

 proceed to consider trunks as distributed into dis- 

 tinct species according to the peculiarities of their 

 form and structure. The species proper to perfect Its 

 plants are the three following : the stem, the culm, spec 

 and stipe, of which in their order. 



SUBSECTION I. 



The Stem. The stem is the trunk of trees, shrubs. Its figure. 

 under-shrubs, and the greater part of herbs. In most 

 plants it is of a cylindrical form, tapering towards 

 the upper extremity, as in the oak and elm. But in 

 some it is compressed or flattened on both sides, 

 with the edges or angles more or less blunt, as in 

 Flat-stalked Pond-weed ; in some it is triangular,, as 

 in most species of Carex ; in some it is quadrangu- 

 lar, as in Figwort ; in some it is fluted or fun-owed 

 with longitudinal grooves, as in common Cow- 

 parsnip ; in some it is winged,~j~ that is, furnished 

 with a membranaceous and leafy prolongation of the 

 angles, as in Narrow-leaved Lathyrus; and in some it 

 is jointed, that is, having the appearance of a num- 

 ber of pieces joined together, and forming a knot 

 at the point of union, as in the Pink. Such are the 

 most common varieties of figure exhibited in the 



* Phil. Bet, sect. SO, ^ ! &* 8. 



