76 



BOOTS. 



extending perpendicularly, or horizontally, as the case may be ; 

 or thickened roots, in which a store of mucilage is laid up for 

 the use of the plants. The spindle- shaped root (fig. F), is of 

 this description, and many plants have it for instance, the 

 Carrot, Parsnip, Eadish, &c. The truncated root of the DeviTs- 

 bit (fig. G), is also a storehouse for the plant's nourishment ; 



the granules of the Meadow Saxifrage (fig. H), serve the pur- 

 pose, and the Lesser Celandine stores its mucilage in bundle 

 roots (fig. I). Some botanists class the tubers of the Orchis 

 (fig. K), with these thickened feeding- 

 organs, and others consider them more of 

 the nature of underground stems. 



But whether the granule, tuber, or 

 spindle be present or not, the plant is sup- 

 plied with fibres, simple or branched, per- 

 pendicular or horizontal. These are the 

 mouths of the vegetable, by which it imbibes moisture and 

 nourishment from the earth ; the moisture rises through vessels 

 which traverse the whole plant, be it herb, shrub, or tree, 

 reaching to the leaves and the remotest bud before evincing 

 any change ; there it permeates the lungs of the plant, becomes 

 converted into characteristic sap, and gradually descends again 

 by a separate machinery of vessels. The structure of the woody 

 parts of roots corresponds generally with that of the stem, only 

 instead of pith it has in the centre a bundle of woody fibre and 

 vascular tissue. The true root is divided from the stem by a 

 collar, all the parts beneath the collar, whatever their form 

 and nature, may be said to belong to the root, though they may 



