THE VITALITY OF SEEDS.
TARIOUS correspondents of the Standard have contributed
V recently to its pages their experiences of the prolonged germinating power of seeds. This latent power of life is among the most beautiful and poetical attributes of plants. It seems as if many of them were endowed almost with a beneficent will that, come what may to the world, whether parched by drought, scorched by fire, or drowned by
brimming floods of waters, they will in their own good time clothe its surface once again in the tender garment of the spring, and restore verdure to its wasted form. Precise instances of the late germination of seeds are not likely to occur often within individual experience. But among the examples quoted in the Standard are the following. A lady writes that, a necklace belonging to her mother made of large grey seeds called "Job's tears" being broken, she put some of the seeds into a pot, after steeping them in water, and placed them in a cool place, but near to the kitchen range, where she kept them watered frequently. The seeds had holes in them through which the string passed. Notwithstanding this, one grew and developed leaves. The necklace had been in her mother's possession for thirty years at least. Another corre- spondent mentions that he saved seeds of acacias in 1874 which were remarkably fertile in 1882, hardly a seed failing. As the pupae of some moths have been known to remain in sus- pended life for eight years, this retention of vitality in seeds may not be considered extraordinary.
But the more striking examples of what must in all probability be instances of vastly more prolonged "hiber- nation" of seed life are those in which plants come up
almost like magic on ground which has been built over for centuries. Every one will remember the case of the so-called "London rocket," which appeared in immense quantities over the ground on which the houses stood that were destroyed by the Fire of London in 1666. Some- thing of the same kind is quoted by Mr. Amos Mitchell, writing from Woldinghatn, in Durham. In 1848 the old parish church was taken down, to make room for a new one. The earth under the old church was excavated for foundations for the new building, and the soil so taken out was spread over part of the churchyard. Next summer this was covered with a plentiful growth of black henbane (Hyoseyamus niger), a plant which does not grow in the locality. A somewhat similar instance of the sudden appearance of the plant was also quoted from Cambridgeshire. Near Oxford, some twenty years ago, a deep cutting was made, to lay a main drain, and the earth piled up on the bank. It will be borne in mind that the earth on the top, and below the top, of this long mound would be naturally that last thrown out from the trench, which was, as far as we remember, quite five feet deep. The trench went right across a large field of turf used for cricket and football, on which the grass was always carefully mown, and on which for at least fifteen years no flower larger than a daisy had ever grown. Next summer (for the trench had to remain open for some time pending alterations else- where) the earth thrown out was one blaze of scarlet poppies. The seed must have remained in the soil for at least fifteen years without germination. Yet this itself seems a curious fact. Why, in the natural course of moisture and heat, had it not either flowered or rotted away ?
There are whole tribes and families of plants which live in regions where drought prevails for months every year that show in a remarkable degree the way in which seeds, and even stems, retain their vitality, and throw some light on the nature of this deferred existence. Much of the flora of the plain districts of South Africa is of this kind, though on the mountain-tops, where the south-western clouds condense in the hot season, they are replaced by a quite different, water-loving vegetation. The famous "rose of Sharon" (a name given also to another plant) is a good example of these "arid belt" sur- vivals. The plant grows like a little thorn tree, about as large as an Eton football, but sometimes not. larger than a cricket ball, and has one tap root of no great length. In the dry season it loses its leaves, and the twigs and branches all curl inwards, till it looks something like a little basket of rough wicker. In the desert storms the root often comes out from the sand, and the plant rolls before the wind like a ball. Should it roll into a stream or pool, it is said that the little branches uncurl, buds come out, and blossoms and seeds appear. Hardly crediting this, the writer took one of these plants, which had lain aside in a drawer for years, and had for six months been kept in a box in a room near some hot- water pipes, and placed it in a large glass bowl of water. Marvellous to say, in three hours tbe tightly clinched " fingArs " had opened. In a short time, instead of being like a wicker ball, it was cup-shaped, and then saucer- shaped. In two days green swellings appeared, and these opening, disclosed something which was either flower or seeds, but which, being contained in little bud-like eases that opened, were possibly the latter. Plants appear with astonishing rapidity in places where it would be imagined that the seeds must have been dormant in the ground, as there is no visible agency to sow them. It was noted in a letter on surviving London flowers in the Times last week that in the parish of Fulham alone one hundred and thirty species of flowering plants were collected last year, and that many of these sprang up on rubbish-heaps and soil which had been left for building purposes, but which had formerly been most carefully tended market gardens, where " weeds " of all kinds
have been severely discouraged for generations. It takes often as long as twenty years before earthworms will frequent soil reclaimed from the sea. Yet this soil will in many cases be covered with grass, weeds, and flowers in five or six years. In the same way, such unpromising places as old brick-
yards, where all the soil has been excavated for some depth, on being abandoned are seen in a single year to be covered with a dense and beautiful growth of tall shrubby weeds and flowers, the dock and the oxeye daisy being perhaps the most conspicuous.
The case of postponed vitality in seeds which has roused the most interest has been the much-disputed vitality of "mummy wheat." It was never quite proved that these seeds might not grow, though a great deal of curious evidence was forthcoming to show that in particular instances persons who grew grain taken from mummy-cases had not been careful to see that it was that originally placed in them. Ibrahim Pasha, for example, was in the habit of presenting distinguished guests with mummy - cases as mementos of visits to Egypt. But these cases, of which he kept a stock, were stored in the Khedive's stables, and the grain taken from them was oats. Two of these oat grains were taken by the late Mr. J. Macgregor, of Rob Roy' fame, from a case given by the Khedive to the Duke of Sutherland, and they duly grew. But oats did not flourish in the mummy-packing period in Egypt, as the secretary of the Botanic Gardens in Regent's Park pointed out. Also, as against the belief that any wheat could grow after three thousand years, it is pointed out that there is a wheat regularly cultivated in the Levant which is called "mummy wheat." It has branching ears, and derives its name from its resemblance to the grain found in the tombs. A Committee of the British Association considered the question, and reported that no satis- factory evidence was available to prove that wheat taken from these ancient tombs had been known to grow. On the other hand, some ten years ago Mr. Martin Sutton wrote that his firm had repeatedly received corn and peas taken out of mummy-cases, and that these were of good germination, and of unquestioned authenticity :—
"It is true that the Arabs will sell so-called Mummy Wheat,' only grown the previous year, to unsuspecting tourists; but that neither proves that all Mummy Wheat is a fraud, nor that true Mummy Wheat will not grow if sown immediately it is taken out of the mummy-cases, under suitable conditions, and before the atmosphere has had time to destroy its vitality. Experiments I have carried on personally for many years past in the prepara- tion and packing of seeds for the tropics, make it clear to me that their vitality can be almost indefinitely prolonged by close confinement, absolute protection from the atmosphere, together with that high degree of desiccation before packing, which was naturally brought about by the Egyptian climate, but which we have to imitate artificially as nearly as possible. Surely the fact that, for so many years, by such treatment the germinating power has been preserved of some of the most delicate seeds (which, under ordinary circumstances, would be valueless twelve months after harvest), is sufficient to indicate the possibilities in this direction."
Those who have grown the pretty and curious " mummy " peas in English gardens will, no doubt, be stimulated by this opinion to verify their real origin. It has been pointed out that as some seeds which can germinate in four days can defer it for seven years—a difference in proportion of 4 to 2,557— the known vitality of seeds is on a very high mathematical scale.
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