scion. When
fixed, the top should be securely fastened by tying it to the pot, or by
means of stakes. For this last operation, a little patience and care are
necessary to make the stocks and scions fit properly; but if the rules
that apply to grafting are properly followed, there will be little fear
of the operation failing. In the accompanying illustrations, we have a
small Mamillaria stem grafted on to the apex of the tall
quadrangular-stemmed, night-flowering Cereus (Fig. 7), and also a
cylindrical-stemmed Opuntia worked on a branch of the flat,
battledore-like Indian Fig (Fig. 8.)

[Illustration: FIG. 7.--GRAFT OF MAMILLARIA RECURVA ON CEREUS
NYCTICALUS.]

[Illustration: FIG. 8.--GRAFT OF OPUNTIA DECIPIENS ON O. FICUS-INDICA.]

In the hands of a skilful cultivator, the different Cactuses may be made
to unite with one another almost as easily as clay under the moulder's
hands; whilst even to the amateur, Cactuses afford the easiest of
subjects for observing the results of grafting.

CHAPTER V.

THE GENUS EPIPHYLLUM.

(From epi upon, and phyllon, a leaf).

It is now about a century since some of the most beautiful of Cactaceous
plants came into cultivation in this country, and amongst them was the
plant now known as E. truncatum, but then called Cactus Epiphyllum; the
name Cactus being used in a generic sense, and not, as now, merely as a
general term for the Natural Order. Introduced so early, and at once
finding great favour as a curious and beautiful flowering plant, E.
truncatum has been, and is still, extensively cultivated, and numerous
varieties of it have, as a consequence, originated in English gardens.
We do not use the seeds of these plants for their propagation, unless
new varieties are desired, when we must begin by fertilising the
flowers, and thus obtain seeds, which should be sown and grown on till
the plants flower.

Epiphyllums have already "broken" from their original or wild
characters, and are, therefore, likely to yield distinct varieties from
the first sowing. In the forests which clothe the slopes of the Organ
Mountains, in Brazil, the Epiphyllums are found in great abundance,
growing upon the trunks and branches of large trees, and occasionally on
the ground or upon rocks, up to an elevation of 6000 ft. It was here that
Gardner, when travelling in South America, found E. truncatum growing in
great luxuriance, and along with it the species known as E.
Russellianum, which h