120 ON THE ORIGIN AND FORMATION OF ROOTS. 



If a circle of If a portion of the bark of a vine, or otiier tree, which 

 off. roots'pro I'tadily emits roots, be taken off in a circle extending round 

 ceeil from the its stem, SO as to intercept entirely the passat^e of any fluid 

 p I 101 ov , tj^,.Qyg.|^ the bark; and any body which contains much mois- 

 ture be applied, numerous roots will »oon be emitted into 

 it immediately abovt^ the decorticated s>)ace, but never im- 

 mediately beneath it: and when the alburnum in the, decor- 

 and buds from ticated spaces has become lifeletJS to a considerable depth, 

 low/^"^ '"" ^ buds are usually protruded beneath, but never immediately 

 above it, apparently owing to the obstruction of the ascend- 

 ing sap. The roots which are emitted in the preceeding 

 case, do not appear in any degree to differ from those which 

 descend from the radicles of germinating seeds; and both 

 appareutl;, devive their matter from the flluitl which descends 

 through the cortical vessels. 

 Varietie';of 'I'liere are several varieties of the apple-tree, the trunks 



tae apple tree a^d branches of which are almost covered with rouyh ex* 

 haveexcres . _ . ° 



cence^ foraged crescences, formed by congeries of points, which would iiave 



by points ihit become roots under favourable circumstances; and such va» 



would liiive . . 



become roo's. neties are always very readily propagated by cuttmgs. Hav-; 



These readily ii^tr thus ob iiined a considerable number of plants of one 

 proi/agated by , , • • i i ,■ i • 



cuttiags. ot these var eties, the excrescences began to forrn upon their 



stems when two years old, and mould being then applied to 



them in the spring, numerous roots were emitted into it early 



in the summer. The mould was at the same time raised 



round, and applied to, the stems of other trees of the same 



age and variety, and in every respect similar, except that 



the tops of the latter were cut otf a short distance above the 



lowest excrescence, so that there were no buds or leaves from 



which sap could descend to generate or feed new roots ; and 



Hoots & buds under these circumstances no roots, but numerous buds were 



Seemingly con- gjj^-|.j.^j^ and these buds all sprang from the spaces and 



▼ertiDie. . ••, ity^ • iivii 



points, which under dmerent circumstances had attorded 



roots. The tops of the trees last mentioned, having been 

 divided into pieces of ten inches long, were planted as cut- 

 tings, and roots were by these emitted from the lowest eX'? 

 crescences beneath the soil, and buds from the uppermost of 

 those above it. 

 but buds pro- 1 had anticipated the result of each of the preceding ex- 

 ceed rum I e pg^jj^g^fg . y^^^ ^hat I supposed, or now suppose, that roots 



