60 BUDS. 



haust the soil at the extremities of the roots only, but it was 

 reserved for Sennebier to demonstrate by a very simple exper- 

 iment, that the spongioles alone absorbed fluids from the earth. 

 This he did by taking two carrots of equal size, and immer- 

 sed the whole of one in water, and the extremities of the roots 

 of another, and he found, that they both absorbed an equal 

 quantity ; but by immersing the whole body of a third, keep- 

 ing only the spongioles out of the water, none of the fluid 

 was absorbed. When the spongiole is destitute of fluid, it 

 contracts, and lies close to the fibre to which it is attached, 

 and hence is not easily discovered in pulling up a root; but 

 by immersing it in a tumbler of water, they become turgid, 

 and are easily observed. 



Section 5. — Buds, 



55. In the axil of the leaf of an exogenous tree or shrub, 

 we may observe in the early part of the summer a small pro- 

 tuberance, which will continue to increase until autumn ; 

 when it will have assumed the form of a conical body com- 

 posed apparently of scales. This is the bud which is desti- 

 ned in the following year to produce a branch, or flowers and 

 fruit These small bodies found in the axils of leaves, are 

 vital points, in which seems to be deposited the vital power 

 during the season of repose, and from which development com- 

 mences as the season of vegetation returns. That thev are 

 important organs, and demand our strictest observation, will 

 be apparent {'rom the fact of their being, in many instances 

 in the vegetable economy, the seat of vitality ;• and it is from 

 this circumstance, that we are enabled to divide individual 

 trees indefinitely by grafting, budding, and by layers. The 

 Leaf Bud may be defined to be the rudiment of a branch, 

 which in its development it always produces. Buds are dis- 

 tinguished by difterent names, according to the point from 

 which they spring, (f they originate in the axils of the 

 leaves they are called regular ; if from any other part of 

 the plant they are called adventitious. 



The regular, or leaf hud has its origin in the pith and me- 

 dullary sheath. The earliest view of the regular leaf bud, we 

 can obtain by dissection, is in the form of an exceedingly 

 minute green body surrounded by a nearly transparent cellu- 

 lar substance situated in the stem immediately below the axil 

 of the leaf. If we examine the buds of the same tree through 

 the season, we shall find that the cellular part becomes 

 opaque, and its place is occupied by scales, and the central 



