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must surely interest the reflective mind. The early stages of growth are 

 sufficiently simple, a single cell, which is the smallest resolvable individual 

 unit of the vegetative body, and is a minute speck of vital substance with 

 well defined limits and definite functions, most notable of which is its power 

 of sub-division. Each actively growing cell splitting in two, both halves 

 speedily attaining the size of its parent with a similar capability of indefinite 

 multiplication. All the young growing parts of plants are composed of such 

 simple elements, and some parts permanently retain this character, such as 

 fleshy fruits and roots, like apples and potatoes. 



• A solitary typical vegetable cell is usually of a spherical or an egg-shape, 

 but except in some of the lowest orders of plants, which are composed of 

 isolated cells, it rarely long retains this primal shape. When aggregated 

 together and suffering pressure on all sides they assume less or more of a 

 dodecahedronal form, that is a figure with twelve sides and twelve angles, 

 but displaying a hexagonal, six sided or honeycomb appearance, in section. 

 This which seems to be the normal form a soft plastic body takes 

 when subjected to equal pressure on every side, may be easily and effectively 

 illustrated by blowing a basin of soap bubbles. This rather childish amuse- 

 ment shows on a large scale the appearance of a sction of parenchymatous 

 tissue, such as a thin slice of young potato when seen under the microscope. 

 Few things are more mobile and changeable than the growing parts of a plant, 

 and very soon the rudimentary ribs of the skeleton of the plant begin to 

 appear. Some of the cells elongate very much, becoming spindle-shaped, 

 tapering to both ends, their extremities overlap, their walls grow hard and 

 thick, and a dense rigid structure is formed known as prosenchyma. This 

 substance which first makes its appearance amongst the ground or fundamental 

 tissue (the parenchyma) of the plant has a tendency to arrange itself in a 

 certain definite manner, usually assuming a wedge shape, with the thin end 

 towards the centre of the stem. These are called vascular bundles, they form 

 the framework of the plants, they are conspicuous and easily discernible as 

 the veins or ribs of leaves, they impart solidity and strength to the stem, and 

 become the firm wood of trees. These bundles form a well-defined circle 

 round the stem, the central portion being the pith, which is invariably 

 parenchymatous, but often in quickly growing plants it becomes absorbed, 

 leaving the centre of the stem hollow as in grasses, umbelliferse, dandelion. 

 In others, such as elders and rushes, it remains a light dry porous substance, 

 whilst in dense woody trees it gets almost squeezed out of sight in the process 

 of growth. 



