MISTLETOE GROWING ON THE OAK.
WHAT CAUSES VARIEGATION?
One would have thought that to prove a fact once in one's lifetime would be enough; but some of the Druidical witchcraft still clings to the Mistletoe, to all appearances, in the vicinity of our seats of learning, and one fact has to be proved over again every twenty years or so, as the subjoined correspondence will show.
I had a printed circular enclosing a return paper with printed headings to be filled up, from William Marshall, Esq., Solicitor, Ely, Cambridgeshire, as to whether the Mistletoe (Viscum album) ever grows upon the Oak?
The following answer I sent by return of post, and I hope it may keep people in the far east at ease for another quarter of a century, and that all others whom the question may concern will have better memories than some of the Cambridge people:—
"Dear Sir,—You are breaking a butterfly on the wheel. Every practical botanist who can read English might have known that the question of the Mistletoe growing on the Oak had been set at rest a quarter of a century since by Mr. Loudon and your humble servant, and the way we did it was published all over Europe and America at the time. But here is a résumé of it. I got a Mistletoe 3 feet in diameter cut from an Oak in the park of the Earl Somers, at Eastnor Castle, Herefordshire. I sent it and a large piece of the Oak branch to Mr. Loudon, and Mr. Loudon exhibited the Oak branch with the large Mistletoe plant attached to it before the Horticultural Society of London. I do not know any practical botanist who saw the specimen. Dr. Lindley is not a practical man; but they say he is a first-rate botanist, and he certainly saw that specimen and lectured on it before the Horticultural Society aforesaid.—I am, &c, D. BEATON."
I had just finished reading Mr. Anderson Henry's most interesting communication on variegation, cross-breeding, and muling of plants, when the Cambridgeshire circular was handed in to me; and to keep on the square, and on the centre of gravity, I replied first to Mr. Marshall to clear an old score out of an old story before venturing on things original with a most welcome coadjutor to these pages. If I had all my life crossed everybody who came near me, I do think you might excuse me and my crossing for having even tempted two such rival philosophers as Mr. Darwin and Mr. Anderson Henry, to contribute to our stock of practical science in THE JOURNAL OF HORTICULTURE. I have said already that all the difference of opinion about the disease of variegated plants was in the meaning of the terms, not in the thing itself.
I have seen the "OLD SHOWMAN," and had some long conversation with him on these, matters. He is a very practical man, and there is a reason why he cannot give his name. Instead of writing for or against anybody's views he went to work like a true philosopher, and instituted experiments in reference to all the views which differed from his own. Instead of yarning or wrangling about curious and obscure points, he went and asked Nature how they stood in her stores. It may be a long while ere he will get an answer, and meantime I promised to go to see his experiments.
According to my experiments—say ten thousand trials, in nine cases out of ten there is actually less disease in a variegated plant than in the green parent which produced it. It is not disease, but a certain condition for which we have no name nearer than the word "disease." The way I prove that is this—the like produces the like in the animal and vegetable kingdoms. A noble lord whom I had known, had three sons, one very spirited was killed in the Peninsular war, the other two lived to over seventy years, and one of them only had a son, an only son. The grandfather was a powerful specimen of the true English gentleman; the grandmother was from a very healthy stock, and she lived to near eighty; the father, mother, uncles, and aunts were all remarkably healthy, and all very large in bone and muscle; but the grandson is a dwarf, now in the House of Lords, perhaps the smallest personage there, but he is very healthy and always was, except once, about his coming of age he had some severe illness. He travelled in all climes. I knew his valet, and he often told me his lordship, notwithstanding his small size, was in the best health of the suite in Syria, in Egypt, and all along on both sides of the Mediterranean. Now, the cause assigned for the extraordinary difference between my lord and his family cast is, that "his growth was stopped by that illness." But he is in fact on the same footing in that respect with one of my variegated seedlings, very different from his parents, but as healthy and as free from any sort of disease as that member of the Upper House. He has three children who, to all appearance are as healthy as larks.
Well, "that illness" whatever it was, works in the vegetable kingdom exactly in the same way—works in making dwarfs, all variegated plants being dwarfs relative to their parents; still they are as healthy and just as capable of producing a healthy offspring as any green species or variety of the race—I mean the race of Pelargonium.
I raised thirty thousand seedlings from the different Variegated Geraniums, beginning with the Golden Chain; and I had less variegated seedlings amongst them than from an equal number of seedlings from green parents.
In six years I raised twenty thousand seedlings from Punch by its own pollen at Shrubland Park, and never saw a single variegated leaf among them all. Here, at Surbiton, no matter which pollen I use on Punch, one-third of the seedlings from it are sure to be blotched and half variegated, and no Geranium is more free from disease than Punch.
In 1853-4 I had some hundreds of seedlings from Flower of the Day by pollen from other variegated sorts, but not a blotch did I ever get in the seedlings; and if Mr. Anderson could give me the white kind which produced all variegated seedlings with Tom Thumb, I am all but quite certain I could get every one of the seedlings from that same cross to be as green as true seedlings from Tom Thumb—that is, after growing the two for one season in my soil.
I had the first of the present race of white-flowering Geraniums in 1816, and I crossed many of them the three following years with the Crystal Palace Scarlet and with Punch, but never got a variegated plant or a good flower in these crosses; but the rose-coloured ones, as Judy, Lady Middleton, and another unnamed rose kind, produced useful flowers with the white race, the Zonale alba, as it was then called. Shrubland Cream and Tricolor were the best of that strain, but they are only house plants and did not obtain much circulation.
Mrs. Vernon is the strongest and most healthy of all the Nosegays, but on my soil no batch of seedlings from it by its own or other pollen comes without several blotched sorts: therefore, I cannot withstand the evidence of my senses against any variegated Geranium whatever being the result of any form of disease.
I have one plant now which was a poor, puny thing from the seed-leaf, a seedling from Baron Hugel by a wild dwarf seedling of my own—an extreme cross as we say. It was three years old before it bloomed in 1869, and it is a very shy bloomer, but it is my principal breeder for minimums; and if poverty of constitution could be called a disease, here is a diseased kind to all intents and purposes, and yet with all our variegated kinds it will not throw off one blotched leaf in any of its seedlings. It will be the father and the mother of a new race of as healthy and free-growing seedlings as Punch, and none of them will ever rise to the stature of the Golden Chain. The first of that dwarf breed will be in the market next spring by the name Harry Heiover, after the author, of "Table Talk and Stable Talk," a charming writer on horses. Harkaway was one of his favourite runners, and this seedling is from the Harkaway Geranium by the pollen of my dumpy.
Pray all ye who believe in this disease question buy Hairy Heiover as soon as it is out, and try it with the pollen of all your diseased seedlings. It is the most minute of the race except Dandy, but is as good a seeder and as free a grower and bloomer as ever was planted out: therefore, it must possess less constitutional powers than any except Dandy; and if there is truth in your disease conceptions, this is the kind which is the most likely in the world to produce diseased seedlings, if it is crossed with diseased male parents. There never was a better chance to prove the question than when you have a great brood of diseased seedlings. Tell me the name of the male parent and I shall repeat the cross with it, and shall lay my head on the block if I do not reproduce the same crosses just as green and horseshoed and quite as healthy as Harry Heiover. I have that confidence in my soil. The diseased parents failed in so many instances to transmit their taint in this soil, that I am justified to make so bold upon it. The American blight which cripples the Apple in the orchard is not a disease, and cannot be transmitted like the canker, which is a true disease, and never fails to appear in the seedlings sooner or later. But like American blight stunts the trees woefully, and so does the blight which produces variegation.
Dr. Morren's vast explanations are just so many airy nothings. Ideas and surmises shall never controvert facts, and the fact is this—give me the two most diseased plants of Geraniums in cultivation, and I shall cross them and confute with the progeny all the high ideas of continental philosophy about this disease. Of that I am quite certain.
Did not Mr. Anderson read as much nonsense about crossing, three or four years back, from a British pen of undoubted scientific strength? and might not some sober people on the Continent who were conversant with the simple facts by practical experience, marvel that such ideas were current in England, just as I was amazed with Dr. Morren's elaborate review? Depend upon it, we are all of us wrong in pinning faith in high-sounding disquisitions from great men, and in overlooking the low and slow progress and process of the simple practitioner who may not know how to put three ideas together in black and white. But a clever practitioner at his pen might very easily go over Dr. Morren's formulae, and confute them by actual examples, one by one, from beginning to end. I may be partly wrong, but I recollect perfectly well that my impression was on reading the article, that I could myself smash many of his best foundation stones to splinters.
Dr. Herbert was the first scientific writer in this country who propounded the doctrine that the world was clothed from the produce of a very few kinds of plants, in his first book on bulbs in 1821, or about that time. In 1836 he recurred to the subject more largely in his "Amaryllidaceae," and when he was persecuted for an atheist, and made to be the author of the "Vestiges of Creation," he vindicated his fame, and gave glimpses of his vast experience on that subject in the Journal of the Horticultural Society, where he exhausted the subject.
But, in conclusion, I have yet some hopes left me that I shall some day discover the true and real cause of variegation in plants. I had a point or two solved in rubbing shoulders with “OLD SHOWMAN,” who is all but a Darwinian from top to toe. I must find time to run down and see him, however, before I can say aught anent that part of the subject; but if I understand him rightly, he will not long cling to the notion that men can change a blade of grass from one form or colour to another, save through the process of Nature by fertilisation.