THE OEGAI^S A2^D PARTS OF PLANTS. 



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these facts is instructive as well as joleasiug, for it indicates 

 that shrubs or trees reared on a light, poor, and shallow 

 soil, will have the greatest quantity of root fibres, and 

 thus be best fitted for transplanting. We have recently 

 observed however, vrith some astonishment, that trees 

 planted on mere sand-hills, near the sea-coast, form 

 scarcely any fibre, but send down long succulent roots to 

 an immense depth — evincing a wonderful power of 

 adapting themselves to circumstances ; for, if they were 

 merely to make lateral fibres in such a spot, like the more 

 humble herbaceous tribes, they must soon perish ; whereas, 

 by striking down so deeply, they have the means of ob- 

 tuining constant moisture in the driest weather. 



Z.—Siiong&lets. 



At the tip of every root or root-fibre there is a growing 

 succulent point, like a piece of half-formed wood, which 

 botanists call the spongiole or spougelet, and which is the 

 medium by which the great bulk of the plant's nutriment 

 is imbibed. This spongelet, which is just an extension of 

 the half-elaborated sap or pulp before it is hardened, is 

 extremely tender, porous, and absorbent, and is i^aler, 

 more fieshy, and transparent than the older parts of the 

 root. It takes up water and other liquids, and imme- 

 diately conveys them throughout its substance as a spouge 

 does. It will receive nothing but liquids, though it does 

 not reject anything they may have in solution. This is a 

 fact of considerable importance, for it shows that what- 

 ever is intended for the food of plants must be capable of 

 being easily reduced to a liquid state. Manures, there- 

 fore, or chemical applications, must either be readily re- 

 ducible by water, or be rendered so by the addition of 

 some acid or other ingredient. 



As the spongelets play so very essential a part in the 

 growth or sustenance of A^egetables, it should always be 

 a leadiug object to preserve and multiply them, where 

 vigorous development is desired, or to lessen their number 

 in ca^e the plant is becoming too exuberant. In removing 

 some plants, therefore, if balls of earth are attached to 

 their roots, a large portion of the spongelets will remain 



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