29 
for the latter, but on cutting them across we find that the 
dry scales which surround them on the outside are not 
followed by fleshy storage scales, all the food material 
being stored in the thick solid stem which makes up the 
bulk of the corm. In their growth and development, 
however, they follow very closely the life history of the 
bulb. Crocuses and Gladioli possess corms, while Lilies, 
Tulips, Hyacinths and Daffodils have true bulbs. The 
bud-like nature of bulbs can’be clearly recognised by 
examining the small swollen buds or duléils which arise 
on the aerial stems of certain species of Lily, and which, 
though unable to give rise immediately to a new flower- 
ing shoot, can gradually be grown on to produce in time 
amature bulb. ~ 
Runners, such as are produced in the Strawberry and 
Violet, are delicate inferat shidets creeping over the surface 
of the soil and becoming readily rooted at their nodes 
when. in contact with the moist soil. In nature they cause 
the very rapid spreading of these plants, and by the decay 
of the portion of the stem which joins them to the parent 
plant they may cause the increase of individuals. They 
are conveniently used for propagating purposes and 
should always be removed from the parental stock as they 
draw nutriment from it and therefore impoverish the latter, 
with the result that they reduce the number of flowers. 
Many plants which do not possess natural means of 
vegetative reproduction can be caused to give rise to new 
individuals by separating certain portions, generally 
lateral shoots, and inducing the same to develop new roots. 
In some instances the formation of these roots is promoted 
before the branch is separated from the plant; this process 
is known as layering. The lower branches of such shrubs 
as Gooseberries and Red Currants may be bent down and 
partially embedded in a shallow trench dug round the 
bush, and filled with light and porous soil. When stimu- 
lated by moisture the buried portions of these branches, 
the tips of which must be allowed to project beyond the 
trench, will produce what are termed adventitious roots, 
and when these are sufficiently well-established, the branch 
may be severed from the parent plant, and the new 
individual will lead an independent existence. It is 
generally found advisable to cut back the projecting por- 
tion of the branch to two or three buds. This method 
can also be employed for Rhododendrons and for more 
