OTx.TlIE REPROiJUCTION OF BUDS. 55\ 



the furface in cou(a(5t with (he bark. It muft, however, be 



admitted, that i\\e inten)a! fubllance of the potatoe correfponds 



more nearly with our ideas oi' a medullary -than of an albiir- 



nous fubftance, and therefore this, with the preceding fa£ls, is 



adduced to prove only that the reproduced buds of thefe 



pUntsare not generated by the cortical fubftance of the root: 



and I tiial! proceed to relate fome experiments on the apple, 



and pear, and plumb-tree, which 1 conceive to prove that the 



reproduced buds oi thofe plants do not fpring from the rae- 



duIJa, 



Having raifed from feeds a very confiderable number of Other Inftances 



plants of each of thefe fpecies in 1802, I partly difengaged ^^j^fjjj'j/p'^^j;^ 



them from the ioil in the autumn, by digging round each ced bads ap- 



piant, which was then raifed about two inches, above its former 1"''^'*/° ^f''"^ 

 ! from the alb ur- 



level. A part of the mould was then removed, and the plants num. 



were cut off about an inch below the points where the feed- 

 leaves formerly grew ; and a portion of the root, about an inch 

 long, without any bud upon it, remained expofed to the air 

 and light. In the beginning of April, I obferved many fmall 

 elevated points on tlie bark of fhele roots, and, removing the 

 whole of the cortical fubtlance, I found that the elevations 

 were occafioned by fmall protuberances on the furface of the 

 alburnum. As the fpring advanced, many minute red points 

 appeared to perforate the bark: thefe foon afTumed the cha- 

 rader of buds, and produced fhoots, in every refpc6l fimilar 

 to thofe which would have fprung from the organized buds of 

 the preceding year. Whether the buds thus reproduced derived 

 any portion of their component parts from the baik or not, I 

 fliall not venture to decide; but I am much difpoled to believe 

 that, like thofe of the potatoe, they fprang from the alburnous 

 fubftance folely. 



The fpace, however, in the annual root, between the medulla They do not 

 and the bark is very fmall ; and therefore it may be contended ^^g^^^j^^j^^^^^"* 

 that the buds in thefe inflances may have originated from the 

 raeduila. I therefore thought it necelfary to repeat fimilar 

 experiments on the roots and trupks of old trees, and by 

 thefe the buds were reproduced precifely in the fame manner 

 ^s the annual roots: and therefore, conceiving myfelf to have 

 proved in a former Memoir,* that the fubitance which has 



* Phil, Tranf. of 1803. 



beei» 



