SECTIONAL TRANSACTIONS.—M". 525 
In some of the Aroids such as Zamioculcas Loddigesii, the pinne, when propagated, 
produce a tuber. This tuber may be looked upon as a proto-embryo, as the tuber 
after it is formed, if laid on its side, seems to have the power of developing a bud 
from any given point. The first growths that take place from Zamioculcas pinne 
are very juvenile in form, and it may take two or three years to produce the adult 
leaves. 
In the scale leaves of Hemanthus, buds can be formed on both the back of the 
scale and on the inside of the scale, but this must not be taken as a general statement 
where scale leaves are used for the propagation of certain genera. 
Bowiea volubilis, whose scales are very thick and fleshy, shows bud formation 
taking place very quickly, but where you find plants such as you have in Ornithogalum, 
the natural reproduction of the scale leaf and the artificial reproduction of the young 
plants are entirely different. In Ornithogalum the young plants that are formed in 
natural reproduction crawl up the back of the scale, being fed with a strand from the 
base of the leaf. But when artificial propagation is resorted to, the buds are formed 
at the basal end of the scale on the inside of the scale and have an entirely different 
outward look. This is due to the fact that in the natural reproduction there is a 
tremendous pressure on the young plant which keeps it in a cylindrical form, whereas 
when artificial reproduction is resorted to the plants are very pointed and thin, and 
more numerous. 
In Drimia the scale leaf has a thick tapering formation. In the younger scale 
leaf the food material is stored between the base of the scale and the centre of the 
scale, but as the scale leaf ages the food material seems to be all forced up to the apex 
of the scale. Buds do not seem to have any special place to arise from, but it seems 
that the buds are formed where there is a collection of food material. 
In nearly all scale leaf propagation it will be found that the young plants given 
off from the scale leaf come to maturity very much more quickly than those raised 
from seed. 
In some of the Coniferz we have plants that may be easily rooted, and here again 
we, in Edinburgh, are working with a system which will never be of much commercial 
service, but which gives an idea of the possibilities of raising these plants by leaves, 
e.g. Ginkgo, Podocarpus and Taxodium. 
The ordinary Daisy which occurs throughout our land is one of the most pro- 
ductive plants that can be found. If one sows a hundred seeds one gets a hundred 
seedlings. If the Daisy leaf is chopped up into twenty-five or thirty pieces, each 
about one-sixteenth of an inch in width, it will be found that a plant or plants are 
formed at the midrib of each portion of the Daisy leaf, and this is how, through the 
distribution of cut leaves by mowers, etc., so many of these plants are found on lawns. 
Dr. T. Swarsrick.—Methods of Fruit Tree Propagation, with special 
reference to Rootstock and Scion Relationships. 
Mr. R. G. Harron.—The influence of Vegetatively Raised Rootstocks wpon 
the Fruit Tree, with special reference to the parts played by the Stem and 
Root Portions in affecting the Scion. 
Exact information is now available which proves that clonal races of vegetative 
rootstocks influence the scion significantly, at least in the first twelve years, the 
amount of total wood growth, the habit of growth, the height and spread of the tree, 
the stem girth, earliness and nature of blossom bud formation, time of blossoming, 
percentage of flowers setting, actual number of fruits borne, size, colour and quality 
of fruit, degree of susceptibility to diseases such as Scab and Mildew, and nutritional 
differences as exhibited by leaf scorch symptoms. 
All these characteristics go to make up ‘rootstock influence,’ which cannot be 
detected merely by measuring the growths of one- or two-year old trees. When such 
trees on clonal roots vary in size, they still behave similarly in all other aspects of 
‘stock effect.’ Although no single term such as ‘ vigorous’ or ‘ semi-dwarfing ’ is 
adequate, vegetative stocks have fallen readily into groups with certain common 
characteristics. 
