THE GENUS PELECYPHORA.
(From pelekyphoros, hatchet-bearing; referring to the shape of the
tubercles.)
IKE Leuchtenbergia, this genus is monotypic, and it is also rare,
difficult to cultivate, and exceptionally interesting in structure. It
is closely related to the Mamillarias, as may be seen, by comparing the
Figure here given with some of them; indeed, it was once known as M.
asellifera, having been described under that name when first introduced,
in 1843. From Mamillaria, however, it differs in the form of its
tubercles, which are hatchet-shaped, and cleft at the apex, where each
division is clothed with small, horny, overlapping scales, not unlike
the back of a woodlouse--hence the specific name.
Cultivation.--The Hatchet Cactus grows very slowly, specimens such as
that represented in our Illustration being many years old. We have seen
healthy plants, freshly imported, grow for a few months, and then
suddenly die, the inside of the stem rotting whilst outside it looked
perfectly healthy. It is always grown on its own roots, but probably it
would thrive better if grafted on the stem of some dwarf Cereus or
Echinocactus.
[Illustration: FIG. 75. PELECYPHORA ASELLIFORMIS.]
Propagation.--The propagation of Pelecyphora is easiest effected by
means of seeds, which, however, are not always procurable. It is stated
by Labouret, a French writer on Cactuses, that the first plants
introduced arrived dead, but a few seeds were found in a withered fruit
on one of the dead stems, and from these the first plants grown in
Europe were raised. M. de Smet of Ghent, had a large stock of this
Cactus a few years ago, and a German nurseryman, H. Hildmann, of
Oranienberg, near Berlin, usually has many young plants of it for sale.
SPECIES.
P. aselliformis (woodlouse-like); Fig. 75.--The size, habit, and
structure of this plant are so well represented in the Figure that
little description is necessary. The stems are simple till they get
about 3 in. high, when they develop offsets about the base, which may
either be removed to form new plants, or allowed to remain and grow into
a specimen like that in the Illustration. The flowers are large for the
size of the plant, and they are developed freely in the apex of the
stems in the early part of the summer. The tube is very short, naked,
and completely hidden by the young mammae; sepals and petals in four
series, the outer one pale purple, the inner of a deep purple colour;
stamens very numerous, and the stigma has only four erect lobes. The
plant was first described from examples cultivated in Berlin in 1843,
but the flowers were not known till 1858. There are several varieties
known, viz., P. a. concolor, which is distinguished by the whole of the
flower being deep purple in colour; P. a. pectinata has larger scales
(spine-tufts); and P. a. cristata is, as its name denotes a kind of
cockscomb or crested form. They are all natives of Mexico.