1900 SUPPLEMENT—RECENT INTRODUCTIONS, &C. 177 
Cacti—continued. 
Seeds. Good fresh seeds of Cactaceous plants germinate 
in from two to four weeks after sowing, if placed in a warm 
house or on a hotbed with a temperature of S80deg. If 
sown in a lower temperature, the time they take to 
vegetate is longer; but, unless in a very low degree of 
heat, the seeds, if good, and if properly managed as regards 
soil and water, rarely fatl to germinate. For all the kinds, 
pots or pans containing drainage to within 2in. of the top, 
and then filled up with finely-sifted loam and sand, three 
parts of the former to one of the latter, and pressed down 
moderately firm, will be found to answer. If the soil be 
moist at the time of sowing the seeds, it will not be 
necessary to water it for a day or two. The seeds should 
be scattered thinly over the surface of the soil, and then 
covered with about tin. of soil. Over this, a pane of glass 
may be placed, and should remain till the seedlings appear 
above the soil. Should the position where the seeds are to 
be raised be in a room windoy, this pane of glass will be 
found very useful in preventing the dry air of the room 
from absorbing all the moisture from the soil about the 
seeds. For the germination of Cactus, and indeed of all 
seeds, a certain amount of moisture must be constantly 
Fic. 190.—SEEDLINGS OF CEREuS. 
a, One month after germination. 6b, Two months after germina- 
tion. ” Three months after germination. (Magnified six 
times. ; 
present in the soil; and after a seed has commenced to 
grow, to allow it to get dry is to run the risk of killing it. 
The seeds of Cactuses may be sown at any time in the 
year; but it is best to sow in spring, as, after germinating, 
the young plants have the summer before them in which to 
attain sufficient strength to enable them to pass through 
the winter withont suffering; whereas plants raised from 
antumn-sown seeds have often a poor chance of surviving 
through the winter, unless treated with great care. The 
seeds of all Cactuses are small, and therefore the seedlings 
are at first tiny globular masses of watery flesh, very 
different from what we find in the seedlings of ordinary 
garden plants. The form of the seedling of a species of 
Cereus is shown at Fig. 190, and its transition froma small 
globule-like mass of flesh to the spine-clothed stem, which 
characterises this genus, is also represented. At a we see 
the young plant after it has emerged from the seed, the 
outer shell of which was attached to one of the sides of the 
aperture at the top till about a week before the drawing 
was made. At b, the further swelling and opening out, as 
it were, of what, in botanical language, is known as the 
cotyledon stage of development, will be seen; a month 
afterwards, this will have assumed the shape of a very 
Vol. V. 
Cacti—continued. 
small Cereus. It is interesting to note how the soft fleshy 
mass which first grows out of the seedis nothing more than 
a little bag of food with a tiny growing point fixed in its 
top, and that, as the growing point increases, the food-bag 
decreases, till finally the whole of the latter becomes 
absorbed into the young stem, which is now capable of 
obtaining nourishment by means of its newly-formed roots. 
In the genus Opuntia, the cotyledon stage (see Fig. 749, 
Vol. II.) of the plant is different from that of the Cereus, 
and is more like that of a Cucumber. Still, though the 
form is different, the purpose of the two cotyledons and 
the juicy stem in the seedling Opuntia is the same as in 
the Cereus; and, as the growing point develops, the 
cotyledons shrivel up and fall off, the plant food they 
contained having passed into that part of the young 
seedling which was to be permanent. 
The seedlings of these two genera serve as an illus- 
tration of the process of germination from seed of all 
the Cactuses ; and it must be evident that there is much 
that is singular and full of interest in raising these plants 
from seeds. As soon as the seedlings are large enough to 
be handled, they may be planted separately in small pots, 
using a compost similar to, but slightly coarser than, that 
in which the seeds were sown. The soil should be kept 
moist till the summer is over, and after that, till the return 
of warm sunny weather, it will be found safest to keep the 
seedlings on the dry side, a little water only being given at 
intervals of a week, and only when the sun is shining upon 
the plants. 
To obtain seeds from cultivated plants, it is necessary, 
in order to ensure fertilisation, that the top of the stigma 
should be dusted over with the dust-like pollen from the 
anthers. This may be done by means of a small camel- 
hair brush; this should be moistened in the mouth 
and then pushed among the anthers till covered with 
pollen, which may then be gently rubbed on to the stigma. 
A warm, sunny morning is the most suitable time for this 
operation, as fertilisation takes place much more readily 
under the influence of bright sunshine than at any other 
time. Some Cactuses have their floral organs so arranged 
as to be capable of self-fertilisation; still, it is always 
as well to give them assistance. The night-flowering 
species must of course be fertilised either at night 
or very early in the morning. By using the pollen 
from one kind for dusting on to the stigma of another, 
hybrids may be obtained, and it is owing to the readiness 
with which the plants of this family cross with each other 
that so many hybrids and forms of the genera Epiphyllum 
and Phyllocactus have been raised. It would be useless to 
attempt such a cross as Epiphyllum with Cereus giganteus, 
because of their widely different natures; but such crosses 
as Epiphyllum with Phyllocactus, and Cereus flagelliformis 
with C. speciosissimus, have been brought about. 
Cuttings. No plants are more readily increased from 
stem-cuttings than Cactuses; for, be the cutting 20ft. high, 
or only as large as a thimble, it strikes root readily if 
placed in a warm temperature and kept slightly moist. At 
Kew, it is the common practice, when the large-growing 
specimens get too tall for the house in which they are 
grown, to cut off the top of the stem to a length of 6ft. or 
8ft., and plant it in a pot of soil to form a new plant. The 
old base is kept for stock, as it often happens that just 
below the point where the stem was severed, lateral buds 
are developed, and these, when grown into branches, are 
removed and used as cuttings. Large Opuntias are 
treated in the same way, with the almost invariable result 
that even the largest branches root freely, and are in no 
way injured by what appears to be exceedingly rough 
treatment. “Large cuttings striking root so freely, it must 
follow that small cuttings: will likewise soon form roots. 
In fact, there is not one species in cultivation which may 
not be easily multiplied by means of cuttings. The 
nature of a Cactus stem is so very different from the 
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