Chap. XI. GKAFT-ny'BKlU!^, 413 



its native woods, the flowers change colour, even dnrmg the first 

 year.*' It is notorious that the improved varieties of tlie Heai'ts- 

 ease ( Viota tricuJor), wlien transplanted, often produce flowers widely 

 diftere7it in size, form, and colour : for instance, I transplanted a 

 large uniformly-coloured dark purple variety, whilst in full flower, 

 and it then produced much smaller, more elongated flowers, with 

 the lower petals yellow ; these were succeeded by flowers marked 

 with large purple spots, and ultimately, towards the end of the 

 same summer, by the original large dark purple flowers. The 

 slight changes which some fruit-trees undergo from lieiug grafted 

 and regrafted on varioits stocks,"*** were considered by Andrew 

 Knight^" as closely allied to "sporting branches," or bud- variations. 

 Again, we have the case of young fruit-trees changing their 

 character as they grow old; seedling pears, for instance, lose with 

 age their s^jines and improve in the flavour of their fruit. Weeping 

 birch-trees, when grafted on the common variety, do not acquire a 

 perfect pendulous habit until they grow old : on the other hand, I 

 shall hereafter give the case of some weeping ashes which slowly 

 and gradually assumed an iti^right habit of growth. All such 

 changes, dependent on age, may be compared with the changes, 

 alluded to in the last chapter, which many trees naturally undergo; 

 as in the case of the Deodar and Cedar of Lebanon, which are 

 unlike in youth, whilst they closely resemble each other in old 

 age ; and as with certain oaks, and with some varieties of the lime 

 and hawthorn.^" 



Graft-hyhvids. — Before giving a summary on Bud- variation I 

 will discttss some singular and anomalous cases, which are 

 more or less closel}' related to this same stibject. I will 

 begin Avith the famotts case of Adam's laburnum or Cijiims 

 adami, a form or hybrid intermediate between two very dis- 

 tinct sjiecies, namely, C laburnum and purpureus, the common 

 and purple laburnum ; but as this tree has often been 

 described, I will be as brief as I can. 



Throughout Europe, in different soils and under different climates, 



'" Godron, ' De I'Esp^ce,' torn. ii. p. of the Aria. The grafted shoots were 



84. also much hardii-r, and flowered 



"' M. Carrifere has lately described, earlier, than those on the ungrafted 



iu the 'Revue Horticole,' (Dec. 1, Aria. 



1866, p. 457,) an e.xtraordinary case. *'• 'Transact. Hurt. Soc.,' vol ii. ji. 



He twice inserted grafts of the Aria 160. 



w.s^tfct on thorn-trees ( e/)W(?s) growing "" For the cases of oaks, .«?<? Aljih. 



in pots ; and the grafts, as tliey grew, De Candolle in ' Bibl. Uuivers.,* 



produced shoots with bark, buds, Geneva, Nov. 1862 ; for limes, ike, 



leaves, petioles, petals, and flower- Loudon's ' Gard JIag.,' vol. xi., 18a5j 



stalks, all widely dilVerent from those p. 503. 



