Mr. Editor:- Will you allow an old subscriber, a true lover of Cactae, and not an unsuccessful cultivator of these plants, a corner in your valuable columns, for a few remarks called forth by an article on " Cactae " in your number of Sep-tember?

The writer of that article says, that "Cactae have no distinct difference of petal, wood, bark, or leaf; that they have no leaves, the entire substance of the plant being a mass of matter, which may be called a branch, or frond, but never a leaf." Now, although in many instances these plants are not as perfectly constituted, with regard to wood, bark, and leaf, as an oak or an elm, yet very many of them have leaves just as apparent and just as perfect in every respect as either of these trees. Take one whole section of the " Pereskiae," for instance - those with flat leaves, such as P. aculeata, P. Bleo, P. grandiflora, P. zinniaeflora, etc, etc., in what do their leaves differ from those of a "camellia" or a "laurel?" They have, moreover, both perfect wood and bark, and so have many " Opuntiss," which is most conspicuous in O. Braziliense, and in all the tribe when old.

Another section of "Pereskias," and most "Opuntiae," have deciduous leaves, " cylindrical" to be sure, but so are also those of Grevillia, Sedum, Mesembryan-themum, and many other plants. Besides, in a botanical sense, the shape of the leaf is of no consequence; it is an organ in which the sap is elaborated through that organ's surface, by contact with the air, as necessary to the life of the plant as lungs to an animal, and therefore must exist in some shape or another, or the plant can not live.

The subject has not been very much studied, but it is supposed by many hotanists, among others by Labouret, (who has written a very excellent hand-book of Cartas), that the "tubercular" or " mammae," play the part of leaves in such of these plants as lack them in a more conspicuous shape. With regard to " petals," I must own I never saw a Cactus flower without them, and they appear to me to have as "distinct a difference " from the other parts of the plant as the petal of a rose, a "petunia," or a "mesembryanthemum." The fact that a frond, or " piece of a frond," will readily root and form a perfect plant, is by no mean peculiar to " Cactaa," or even to succulents in general; your readers need not be told what a vast number of plants are usually propagated in this way. The common "scarlet Geranium," for instance, will readily root a piece of young green shoot, let it be taken from the "side " or any where else, so that it have at least one eye above ground; and so must the piece of Cactus, or it will not grow; in both these cases you have a piece of succulent matter which differs in no respect, and an eye containing the embryo plant.

The Geranium will also strike upside-downward, bat in this case, as also in that of the Cactus, the growth is retarded.

I agree with the writer that Cactae require, more than any other plants, a season of rest; but I should be sorry to subject any valuable specimens to a " total abstinence from water for twelve months, even at a temperature of 80° Fahr." The fact is, that most of these plants show a tendency to vegetate towards spring, sooner or later, according to the mildness of the weather without, and this tendency must be fostered by artificial heat and consequent judicious watering and ventilation, or all pushing flower-buds will turn to wood, i. e., branches or fronds, in Opuntiae and Cerei, offsets in most Echinopsi, Echinocacti, and Mammillaria,*

The cultivation of Cactae in collections has very much increased of late throughout the Continent and in Great Britain.

In Paris, the kinds which bloom so easily, and are so readily propagated, as C. speciosissimus and its hybrids, Echinopsis Eyrisii and others, Echinocactus Ottonis, and sundry Phyllocacti and Epiphylli, may be had in the flower-markets for from 5 to 25 sous each.

Many kinds are expensive. Echinocactus Californicas never sells under $4 to $5, as a mere offset, $20 when rooted, and a couple of inches in diameter; E. C. Texensis, $5 to $15; Cerei, from 25 cents to $25. Of C. Uncinates there are only four or five specimens in Europe; they sold, without roots, at $20 each this summer. Young Leuchtembergisd and Anhalonnim bring $4 each, when they are to be had at all. Of Peleoyphora there is but one specimen in Paris, purchased at $25, and one or two at Ghent. Of the different Discocacti, not one single specimen exists in Europe. Melocacti do not do well in France, when imported as adults, with their "cephalium " ready formed; they have hitherto died off; there are plenty of European seedlings, however, in the trade, which may prove more hardy, but as yet they are very young, and have many winters' trial to undergo before they show their " cephalium," and are fit to take their place as specimens of flowering plants. On the subject of Melocacti, I can not conceive how the writer above alluded to can have managed to "hybridize "these plants. The flowers are so minute, so hidden under the wool and spines of the "cephalium," that it seems to me next to impossible to impregnate them artificially.

If there is no mistake, his seedlings will be welcome in European collections, where, I have no doubt, they would meet with a ready sale. I, for one, would be glad to purchase a few of them.

* For farther particulars on the subject of cultivation, see divers articles of the writer's, signed with the pseudo-name A. B. C, in the Horticultural Cabinet, London, and Horticulture Francais, Paris.

I may add, in a general way, that an amateur on the Continent will be able to form a collection of:

100

distinct kinds for an average of

15

sous

each.

200

"

"

"

"

3

francs

"

300

"

"

"

" "

5

"

"

400

"

"

"

- . .

10

"

"

500

"

"

"

• • .

10

"

"

600

"

"

"

. . •

10

"

"

The last will include all the tribes, genera, and species known and described, but of course a vast number of mere varieties and hybrids, and can not be got together without a good deal of trouble. At this figure most rare kinds will only be young specimens, as some of these (as large plants) will fetch 1,000 francs each. The finest collection is that of the late Prince de Salm Dyck, near Bonn, on the Rhine.

There are many dealers exclusively devoted to the propagation and sale of "succulents" in every capital on the Continent, and one or two in London. They all seem to drive a thriving business. Agaveas and Yuccas are at present much in vogue; rare kinds of the former bring very high prices. VerschafFelt, of Ghent, exhibited in Paris, at the last show of the Imperial Society, a few days since, two new kinds, A. Verschaffeltii and another not yet named, offsets of which he quotes at 100 francs each. I lately saw, at a dealer's in Havre some splendid specimens of Yucca aloefolia variegata, for which he gets about 300 francs each; Y. quadricolor of same size would bring at least 1,000 franca, Versailles, France, 26th Sept., 1861.

[A valuable and interesting contribution, for which we desire to return Mr. Palmer our best thanks. Mr. Barker, to whose article he refers, will no doubt respond. - Ed].