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JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



There is another kind in which all the leaves are on one vertical line 

 with a strong torsion of the stem. In this case every two alternate leaves 

 of the row constitute the original pairs of opposite and decussate leaves ; 

 but each has been uplifted till they all fall into line. 



Spinescence. — Plants growing naturally in dry situations are often 

 spiny, as the furze and needle furze ; but when spiny plants are grown 

 in an abundance of moisture, the spinescence may disappear entirely ; so 

 that although a spineless gooseberry may be called a sport, the cause is 

 reasonably suspected to be an adaptation to moisture. 



Bud-sports. — As all the organs of a flower are recognised as having a 

 foliar origin, so leaf-buds and flower-buds can be interchangeable. 



In some plants the flowers are normally replaced by vegetative buds, 

 or bulbils, as in the case of species of Polygonum and Allium. 



In grasses, sedges, and rushes &c, it occasionally happens that the 

 florets are replaced by leafy buds. The whole panicle sooner or later falls 

 to the ground, when they strike root and so give rise to independent 

 plants. 



Of course vegetative methods of propagation are perfectly normal and 

 of many kinds ; but it is only when a plant suddenly undertakes to do it 

 in some abnormal way that it is regarded as a sport. 



Leaves. — The sporting of leaves is very various. In some cases it is 

 apparently due to the atrophy, as in spinescent foliage, and the cut- 

 leaved or laciniated varieties ; sometimes to hypertrophy, as in crisped 

 foliage of the savoys and parsley, Sec. Varieties of variegation are in- 

 numerable, and they have mostly arisen by accidental sporting ; but the 

 causes are obscure. 



Cut-leaved Varieties. — This form of foliage is now characteristic of 

 varieties of many kinds of trees, as of the beech, blackberry, &c. They 

 cannot be depended upon for constancy when raised by seed ; but they 

 have arisen as sports in the ordinary kind. It can be propagated by 

 cuttings and grafts when the character remains permanent ; though a 

 branch on such a tree may, and often does, "revert" to the ordinary 

 form. This is very frequently the case with variegated shrubs and trees, 

 shoots with entirely green leaves only too frequently appearing and de- 

 preciating the value and appearance of the plant. When differences thus 

 appear suddenly they are called sports ; but precisely similar conditions 

 often normally exist on some plants, which are thus always characterised 

 by having dissected foliage ; as, e.g. Malva moschata, Broussonetia papy- 

 rifera, the Japanese honeysuckle, &c. The common snowberry may 

 perhaps help us to an interpretation of the phenomenon. Selecting a 

 vigorous yearly shoot, the following facts may be noticed : — The first 

 formed leaves at the base, where energy is not yet vigorous, are small and 

 entire ; towards the middle of the shoot, where energy is most vigorous, the 

 leaves are much larger but more or less lobed. At the close of the year's 

 shoot, the leaves are again small, like the first formed, and entire. It appears 

 from this that at the middle period of growth, when vigour is at a maximum, 

 materials fall short of what is required to make the largest leaves com- . 

 plete ; but as these features may be seen in every bush, every year, they 

 have become fixed and hereditary. 



Again, as leaves of a plant, although complete below, often become 



