Norember 6, 1884. ] 
JOURNAL OF HORTICULTURE AND COTTAGE GARDENER. 
423 
exhibiting a similar sensitiveness, but the case is not quite analogous to that 
of the Berberis, the arrangement in that flower being more of a mechanical 
nature. 
O. Salmiana, Parmentier .—One of the most attractive of the slender- 
growing species with cylindrical stems is that upon which has been bestowed 
the name of a celebrated patron of the Cactus family, Prince Salm-Dyck. 
It is a native of Brazil, and was introduced about 1850, having been received 
at Kew from the continent about that time, and it has since then become 
one of the most favourite forms of the group in cultivation. As shown in 
fig. 70, which is a very slightly reduced representation of a portion of the 
plant, the stems are very slender and cylindrical, with numerous little tufts 
of small spines, and bearing near the summit dense clusters of very pretty 
neat open flowers. These are 1 ^ to 2 inches in diameter, creamy white, the 
buds and outer surface of the petals being tinted with red, which gives a 
most pleasing appearance to the plant. It requires to be grown in a warm 
position, and needs a light soil, loam and leaf soil in equal parts having 
been found to suit it admirably. It is well worthy of more extended 
cultivation. 
O. ARBORESCEXS (the Walking Stick or Elk-Horn Cactus).—This species, 
•which grows in Colorado and contiguous districts,has a narrow much-branched 
stem, which often rises to a considerable height. These stems are cut, and 
after the fleshy substance has been removed there remains a hard woody 
network of thick fibres, which is converted into walking sticks. Specimens 
of this kind from Colorado, presented by E. G-. Loder, Esq., are included in the 
collection at the Kew Museum. The same gentleman has also sent me some 
beautiful photographs of the scenery where this plant abounds, one 
•view of the Grand Canon of the Arkansas being especially remarkable. 
Amongst other notable species the following especially deserve 
brief mention:—0. aurantiaca (Cactus aurantiacus), a Chilian species, 
with bright orange flowers and irregularly terete stems. Introduced 
in 1824. 0. brasiliensis, with irregularly flattened and branching stems, 
bearing scattered solitary dark spines 1 to 2 inches long, and pale yellow 
flowers 8 inches in diameter. The odour of the ripe fruit has been 
thought to resemble the leafstalks of garden Rhubarb. 0. candelabri- 
formis, a remarkable plant, with flat almost circular branches about 
(» inches long by the same in width, and closely covered with white 
spines. 0. curassavica (Cactus curassavicus), the Pinpillow or Minion 
Prickly Pear, deserves notice for its historical interest. It was one of 
the few Cactem figured in Bradley’s work on Succulent Plants, where it 
is named Opuntia minima Americana spinosissima flore sulphureo, and is 
said to have flowered and fruited in the Duchess of Beaufort’s garden at 
Badminton, and on the authority of the “ Hortus Kewensis ” we learn that it 
was introduced from Curagoa in 1690. The flowers are greenish-yellow, not 
very handsome. 0. cylindrica, a very distinct species, with cylindrical stems 
and spindle-shaped tubercles, each bearing a tuft of spines at its summit. The 
flowers are red, 2 inches in diameter, and the plant was introduced to 
England in 1799, 
O. Darwixii.— This species is interesting, as having been discovered by 
Mr. Charles Darwin in Patagonia, and it is mentioned by him in his 
“Naturalist’s Voyage Round the World” as follows (p. 165) :—“I found 
here a species of Cactus which was remarkable by the irritability of the 
stamens when I inserted either a piece of stick or the end of my finger in the 
flower. The segments of the perianth also closed on the pistil, but more 
slowly than the stamens. Plants of this family, generally considered as 
tropical, occur in North America in the same high latitude as here—namely, 
in both cases in 47°.” In the volcanic islands of the Galapagos Archipelago 
the same writer found an Opuntia, which was afterwards named 0. gala- 
pageji, a tree-like species 6 to 10 feet high, and this is probably the plant 
mentioned in his account of these islands as “ a great odd-looking Cactus, 
which, with some of the Euphorbiaceae and an Acacia, are the only trees 
which afford any shadp. After the season of heavy rains the islands are 
said to appear for a short time partially green. The volcanic island of 
Fermando Noronha, placed in many respects under nearly similar conditions, 
is the only other country where I have seen a vegetation at all like this of 
the Galapagos Islands.” 0. decumana is an extraordinary plant, represented 
in the Kew collection by a specimen 12 feet high and of considerable age. 
It has huge elliptical flattened branches 12 to 20 inches long and 8 to 10 
broad, with a few spines, the lower older portion of the stem being cylindrical, 
woody, and about 8 inches in diameter. It is a South American plant, has 
orange-coloured flowers, and has been described by various authors under 
the name of O. maxima, Cactus elongatus, and Cactus decumanus. 
O. Dillenii {Cactus Dillenii). —One of the species cultivated at Eltham 
in 1732, being described and figured in Dillenius’ work as Tuna major spinis 
vajidis flavicantibus flore sulphureo. It has flat stems with strong yellow 
spines, and bears yellow flowers 3 to 4 inches in diameter. This plant is 
grown in Teneriffe for its spines, which are employed to secure the clusters 
of cochineal insects to 0. Tuna at the “ sowing ” period already noticed. In 
a group of flowers painted by Miss North at Teneriffe, and now in the North 
Gallery at Kew, this species is well represented, several views of the cochineal 
gardens in which it is employed being also given. In England this Opuntia 
flowers very freely, its large yellow blooms being very attractive. 0. horrida 
well deserves its name, for it is a most formidable plant, the spines 
2 to 3 inches long, very strong, of a peculiar tawny colour, and in clusters of 
seven or eight each. O. imbricata has irregularly cylindrical branching 
stems and tufts of white spines. 0. Kleinite, also with cylindrical stems, 
receives its name from a slight resemblance to some of the Kleinias. O. lep- 
tocaulis is one of the most slender-growing Of)untias, the stems often not 
exceeding one-eighth of an inch thick. 0. leucotricha has a curious appear¬ 
ance, owing to its oval flat branches being closely covered with long white 
spines, which are deflected towards the base of the plant and almost level 
with the surface. O. microdasys is a rather pretty dwarf and much-branched 
species, which with its variety rufida, has numerous small tufts of reddish- 
brown hair-like spines covering the elliptical flattened branches. 0. mona- 
cantha.—This is one of the best known of the flat-stemmed Prickly Pears, 
as it is largely grown for sale with the miniature Cacti. It has dark green 
stems, with scattered solitary spines, and bears neat bright orange-coloured 
flowers. 0. nigricans.— This is another of the largest specimens at Kew 
one old example there being of corresponding dimensions to 0. decumana— 
namely, 12 feet in height, the branches 12 inches long by G inches broad, and 
bearing very dark spines 2 to 3 inches long, the flowers orange-red, and the 
fruits pear-shaped and rich crimson when ripe. This has been described as 
Tuna major (Dillenius), as Cactus Tuna var. nigricans, as Cactus Tuna, and 
as Cactus nigricans, and it appears to be one of the species upon which the 
cochineal insect lives. 
PERESKIA, Mi/ler. 
(The Gooseberry Cactus.) 
In all the preceding genera of the Cacfus family we have been 
reviewing a form of vegetation widely different in appearance from the 
ordinary characters of flowering plants, particularly as regards the stem 
structure, but in the Pereskia by a sudden transition we come to a group 
of plants evidently connecting the family with several orders. The stems 
have lost the bulkiness of many Cactem, and though still fleshy in a 
certain degree, and armed with clusters of spines, they are cylindrical 
and more shrub-like in form, while they bear normal leaves veined like 
the majority of exogens, and often with a distinctly developed stalk 
(petiole). The flowers, too, are very distinct, the petals being rotate— 
that is, spreading like the spokes of a wheel, and in several cases they 
bear a close resemblance to single Roses. The flowers are produced in a 
form of inflorescence, which is not found in any other member of the 
family—namely, clustered or paniculate at the sides or points of the 
branches, and this alone gives the Pereskias a unique appearance, and 
renders them easily recognised. Thirteen species are known, all natives 
of tropical America and the West Indies, but few are in cultivation, and 
these are in England chiefly employed as stocks for other kinds of Cacteae, 
such as the Epiphyllums. 
The genus was named in honour of N. F. Peiresk, a senator of Aix, 
who is said to have “ collected a considerable library and herbarium, but 
published nothing.” The name is sometimes spelled Peirescia. 
P. ActTLEATA, Plumier {Cactus FeresMa, Linnaeus), The Barbadoes 
Gooseberry or Blab Apple. —Though this plant is rarely seen in England 
except as a stock for Epiphyllums, or in course of preparation for that 
purpose, it is decidedly ornamental when trained to the roof of a house and 
allowed to flower. Its white blooms are much like a single Rose, or some 
form of Rubus, are produced in panicles of a dozen or more, slightly drooping 
and very graceful, the narrow white petals and similar green sepals con¬ 
trasting rather pleasingly. The leaves are ovate or elliptical, 3 to 4 inches 
long, 2 to 3 inches broad, dark shining green ; and the stems, which attain the 
height of 10 to 12 feet, and 1 to 4 inches in diameter, have numerous dense 
clusters of strong spines. As the popular name implies, the fruit is much 
like a Gooseberry, the similarity being observable not only in the form and 
size, but in the colour and flavour also, and in some of the West Indian 
Islands, especially in Barbadoes, a much valued preserve is prepared from 
the fruits, and is said to possess expectorant qualities. The use of this plant 
as a stock has been described under Epiphyllum, and it need only be added 
that it can be raised from seeds as well as from cuttings, the latter being, 
however, the quicker method. The time of flowering varies, sometimes 
occurring in the summer months, July, August, or September, and at otheis 
in early spring. 
This species has been an inhabitant of English gardens for a great 
number of years, as it is recorded as included in the Hampton Court 
collection in 1696, and is mentioned by Dillenius thirty or forty years sub¬ 
sequently. When it was first used as a stock for Epiphyllums is uncertain, 
but it was employed in that way early in the present century. Several 
varieties have been described differing in the leaves, snch as lanceolata, 
rotundifolia, and rubescens, the names indicating the characters. 
P. Blf.o, Decandolle. —An extremely distinct and bold-looking plant, 
with strong cylindrical stems, clusters of long formidable spines, and large 
dark green obovate leaves, 4 to 6 inches long, and 3 to 4 inches broad. It 
