Works of grant allen, p.1013
Works of Grant Allen, page 1013
Once abroad in the world, he grows apace; and this is necessary, because, about September, he will have to fly off with his affectionate parents on a long, forced journey to warmer winter quarters. Not, of course, that he minds the winter in itself; but the flies and beetles are gone; their sole representatives are now the eggs and chrysalids; mice and lizards have retired into winter quarters; no small birds are about in the unfledged condition where one gets a fair chance with them; and altogether there is nothing for it but to travel south and find more plentiful support in some warmer country.
So southward the family flits, when partridge shooting begins, first over Channel to France, and then on to the Mediterranean. But food is scarce even in Provence and Italy during the winter months; so our wise young shrike and his parents do not loiter about with the invalids and flâneurs at Cannes or Naples; they strike right across sea, viâ Sicily and Tunis, to the Nile Valley. Thence, anticipating Mr. Cecil Rhodes and disregardful of railways, they keep straight on, with glorious views of sea and mountain, past the Mahdi’s land, till they arrive at the great lakes and British South Africa. At least, that is the course pursued by the greater number, though a few more original families (mostly Russian by birth) trend eastward towards the Persian Gulf, and winter, after the now fashionable manner, in India.
During his absence in the south, our shrike grows adult, and also puts on his fine spring colours (which are his courtship suit, intended to charm his prospective mate), just before his return in May to England, or rather to Europe; for of course I do not mean to say that he necessarily comes back to his native country; though there is reason to believe that most migratory birds do really return year after year to the same quarters. They have a summer residence, so to speak, in France or England, and a winter one by the banks of the Zambesi or the Indus. Most butcher-birds that visit Europe in the spring come fairly far north, nesting in Northern France, Southern England, Belgium, Holland, or Germany. Few nest on the Mediterranean, probably because the summer droughts in that arid tract are unfavourable to their food-insects; those that remain in Southern Europe or Western Asia choose, as a rule, the cooler and moister mountain regions, such as the Balkans, the Greek hills, Armenia, and the Caucasus. The English residents fly back from their African home (where they now enjoy the blessings of British rule quite as fully as in Britain) well fattened on juicy southern insects, dressed in their courting dress, and ready for the serious business of settling in life, choosing a mate, and rearing a young family. Indeed, observers in Eastern Africa have noted them during the intermediate period, sitting on the thorny shrubs, such as the Egyptian acacia, which abound in that region, and already adorned in their brilliant breeding plumage in anticipation of their return to their northern quarters.
Some people say that the shrike even makes two nests a year (as the swallow certainly does), one in the north and one in Africa; but this is unlikely, and Dr. Sharpe, of the British Museum, will have nothing to say to it.
It is at the mating season especially that you have a chance, if ever, of catching sight of the butcher-bird himself, seated, all eagerness, on his look-out tower; and enjoying life with the calm begotten of that fine old recipe — a bad heart and a good digestion. He sits and utters his amatory feelings now and again in an abrupt little “chuck, chuck,” which is whipped out suddenly, with a jerk of the head sideways as an appropriate accompaniment. About the same time, too — say the beginning of June — you stand the best chance of coming upon one of the larders, all stocked with fresh meat; for later in the year, when the young are well fledged, the shrike gives up its murderous practices a little, and takes its young on the prowl for themselves in orchards and gardens, in order to accustom them to the habit of catching prey. But I suspect my evil friend of often murdering for mere murder’s sake, as generally happens with predatory animals; they acquire a certain love for the chase as such, and even seem, as one may observe in cats, to delight in cruelty for the sensuous pleasure of inflicting pain on others. Your shrike has no inkling of a conscience. He does wrong boldly, with sublime indifference; and believes himself to the end to be a model father, a tender husband, an ornament to society, and a useful citizen.
V. MARRIAGE AMONG THE CLOVERS
PLANTS marry and give in marriage just as truly as animals. They have their loves and their hatreds, their friendships and their enmities. The marriage customs of many among them are vastly interesting; and yet, in spite of all the attention that has been given to the subject of recent years, comparatively few people are even now aware how quaintly they pair, how varied and curious are their matrimonial arrangements. Most of us, it is true, have heard by this time the bare facts of the case — that flowers are mainly fertilised by the visits of insects: many of us even know that in the majority of instances the little golden dust which we call pollen must be transferred from the hanging bags on one blossom to the sensitive surface of another, or else seed will never be set; but not all of us are aware how intricate and how numerous are the minor devices by which each kind of plant effects this important object in its own fashion. I am going, therefore, in the present paper to describe briefly the marriage customs of two alone among our commonest clovers, which I shall adduce as specimens of the strange variety to be found within the limits of a single type.
To begin with, however, I propose to examine, as a mere introduction, a couple of flowers of a well-known and dainty hot-house begonia, which may help us to the comprehension of the more plebeian clover-heads. Proverbial philosophy has long since taught us that “the longest way round is the shortest way home”; and when I drag in the begonia, which has apparently so little connection with clover, and which is really about as unrelated to it by descent as two flowering plants can well be to one another, you may suspect that I do so for some sufficient reason. The fact is, begonias happen to be plants in which the differences of the sexes are exceptionally well marked, so that they may be apprehended with ease by the naked eye and by every observer, even the most casual. I advise those who have conservatories of their own to verify my statements in this matter on the specimens in their possession; for those who have not, Mr. Enock’s excellent illustrations, which accompany this paper, will serve almost as well as the original objects.
Most cultivated begonias have the flowers on their branches arranged in groups or clusters of three, the central one of which is often a female, while the two outer blossoms are usually males. This is the ordinary plan, but it does not hold good of all the species, some of which, on the contrary, have only one male to each pair of females. Now, these male and female flowers are so very unlike in form and structure, when you come to look into them, that you would hardly believe they belonged to the same plant if you did not find them growing on one branch together. They differ quite as markedly as the peacock differs from the pea-hen, much more markedly than man differs from woman. A glance at No. 1, and then at No. 4, will make this point obvious. You would say, if shown them separately, that these two blossoms must surely be flowers of quite distinct species; yet they hang side by side on one and the same plant like brothers and sisters.
The first point of difference which you will note in the two is that the female begonia, as seen in No. 1, has five petals, while the male, in Nos. 4 and 5, has four only. (I call them petals both for brevity’s sake and because I believe them to be so in reality, though fear of that terrible critic, Dr. Smelfungus, who goes about like a roaring lion seeking whom he may devour, compels me to add that in the learned Doctor’s opinion they are parts of the calyx — a petty distinction with which, but for him, I would not have troubled you.) But what is far more important than the number of the petals is the fact that the female flower has wedged at its back a large triangular-winged ovary, or seed-capsule. It is the possession of this ovary, indeed, that marks it out at once as a female: for by a female plant or animal we mean, of course, the one which lays the eggs, produces the seeds, or becomes the mother of the young individuals. If you compare the back of the female flower in the lower portion of No. 1 with the back of the male flower in No. 5, you will recognise at once the importance of this distinction. The female blossom has a seed-bag, while the male is barren. In No. 2 we have represented one such seed-bag cut open crosswise, so as to show both the projecting wings and the numerous little seeds in the three cells within.
But this is not all: the other parts of the two flowers differ almost equally. The centre of the female blossom is occupied, you will observe, by several twisted and wriggling arms, the upper surface of which is more or less sticky. This surface forms the receptive portion, or mouth of the flower, on which grains of pollen must be duly deposited before the embryo seeds in the capsule below can begin to swell and develop. On the other hand, the centre of the male flower, as seen in No. 4, is occupied by a set of very different organs, the stamens or pollen-bags, whose business it is to produce and shed the fertilising powder. Without pollen to start them, the seeds are useless. In the wild state, any winged insect which visits the plant is likely to alight first on the lip or platform of one or other of the outer male flowers. In his search for honey, which is secreted by the plant at the base of the petals on purpose to allure him, the flying visitor dusts himself over abundantly, though unconsciously, with grains of pollen from the very numerous little sacs which are placed there in a convenient situation with that precise object. He then flies away to the female flower, in which he alights, as a rule, on the central sticky portion (called by botanists the stigma): and as he walks over it in search of the honey at the base of each petal, he turns himself round and round in five directions, and thus unwittingly rubs off the pollen which clings to his legs and hairs, transferring it to the sticky and receptive surface. After visiting and fertilising the female flower in the centre in this manner, he then usually proceeds to visit the second brother beside it, from which he carries away pollen in turn to the next plant he visits. The object of this curious arrangement is that each flower may be fertilised by pollen from another blossom, and, as far as possible, in many instances at least, by pollen from a distinct neighbouring plant. But you will gather at once from what I have said already that each plant must be regarded in strictness not as an individual, but rather as a community or commonwealth, of which the leaves and flowers are the separate members told off to perform different duties. You may compare it, indeed, to a hive of bees, the leaves representing the workers, while the five-petalled flowers are analogous to the queen-bees, and the four-petalled blossoms to the husbands or drones. Nay, more: those of my readers who have begonia plants of their own may observe for themselves another singular resemblance to the habits and manners of honey-bees. For after the drones have done their work in life by fertilising the queen-bee, the prudent workers sting them to death, as being useless mouths, of no further benefit to the community; but the queen-bee necessarily survives to become the mother of young swarms, or future generations. If she were killed, it would be all up with the community. Just so with the begonias; as soon as the male flowers have performed their whole duty in life, by producing and disseminating the grains of pollen which the insects carry away and smear upon the sister blossoms, they break off at the joint shown in the illustrations, and fall to the ground; the plant refuses to feed them any longer, because it has now no use for them: but the fertilised female flowers remain fixed on their stems to produce the seeds, from which will spring in time the future generations.
What, however, do I mean by fertilisation? Well, each pollen-grain, when closely examined under a microscope, looks like a tiny egg, with a very thin shell and very sticky, active contents. As soon as the pollen-grains are rubbed all over the curly branches in the centre of the female flower, they empty their contents down long tubes, which reach at last to the seeds; and under this vivifying influence, the seeds begin to swell and become capable of producing young plants. The pollen, in short, has quickening power. It is for the sake of this final result alone that the flowers exist: they are provided with bright-coloured petals as advertisements to let the insects know where honey may be expected; they secrete the sweet liquid itself in order to induce their winged allies to become common carriers of pollen for the benefit of the begonia; and as soon as each flower has served its purpose in this respect, it drops off or is retained by the plant according as it is or is not wanted in future for its seed-producing properties.
The difference between the brother and sister flowers is even more visible in the bud than in the fully opened blossom. No. 3 shows us this very well in the case of an unopened male blossom. Here the two large petals, afterwards used as platforms for the insect to alight upon, enclose the smaller pair of interior ones, as well as the bunch of yellow stamens. But as these stamens are full of nutriment, and therefore liable to be prematurely attacked by useless gnawing insects, the petal above them is thickened in this part, and in one of the species most cultivated in our green-houses, but not figured here, is provided with little protective hairs, which baffle and keep at bay all hungry aggressors. I may add that the projecting wings on the seed-vessel, well seen in No. 1, and also in the section in No. 2, serve a somewhat similar purpose: they are intended to prevent hostile insects from laying their eggs at the most vulnerable points in the capsule, where the grubs would destroy the seeds within. The thickenings above and below, also to be observed in the lower figure of No. 1, perform a like service. They are devices of the mother to protect her young. You will thus perceive that the begonia has its friends and its enemies in the insect world, and that while it does its best to conciliate the one, it is no less anxious to repel the other. We shall find in the sequel that precisely the same thing is true of the clovers.
To the clovers then, which are our proper subject, I will next proceed. And I began with the begonia by way of introduction, only because that afforded us a case in which the husbands and wives of the community were so distinct from one another that nobody with a pair of eyes in his head could fail to distinguish them when they were once pointed out to him. In the clovers, on the other hand, we have a much more complicated arrangement, and one much less like the ordinary cases with which we are familiar in the animal world. Here, the flowers are collected in heads or clusters, and each flower is in itself at once both male and female. This method, indeed, is common amongst plants; it occurs in by far the greater number of species: the reason why I started with the begonia is just because in that type the sexes are so well and clearly separated in distinct blossoms. In the clovers, however, each separate flower resembles a small peablossom in shape, having four petals, which botanists name respectively, from below upwards, the keel, the two wings, and the standard. These petals are best seen in the single upstanding flower (or “old maid”) represented in No. 9. They are enclosed beneath in a small greenish calyx or cup, and they contain within them ten stamens or pollen-bags, as well as a tiny capsule like a miniature pea-pod. At the tip of this capsule is a small hook — the sensitive surface on which the pollen has to be deposited. You would say at first sight that under such circumstances, male and females being mixed up in one, cross-fertilisation must be impossible — that each flower must surely be fertilised by its own pollen. But the clever clovers have invented an ingenious little device of their own for overcoming this difficulty: the pollen-bags and the sensitive surface of the capsule do not arrive at maturity together. In this way each flower or plant gets fertilised itself at one time by pollen from another plant, and at another time dusts the bee that visits it with its own pollen, which the bee transfers in due course to the next plant it visits.
No. 6 represents part of a plant of Dutch clover — the common white clover of our meadows and pastures. It is called Dutch, not I believe because it is particularly common in Holland more than in other European countries, but because the prudent Dutch were the first agriculturists to collect and export the seed of this particular clover separated from all other seeds of similar but less useful species. It happens to be a particularly good fodder plant, and it grew wild originally throughout the whole of Europe and temperate Asia, from the Mediterranean to the north of Norway. But the seed has now been sown for pasture in almost every country of the civilised world, so that wherever this volume circulates, its readers can find and observe the plant for themselves, “to witness if I lie,” as Macaulay’s Roman poet bluntly puts it. Dutch clover is a rather smooth specimen of its type, not nearly so hairy or silky as most other clovers, for a reason which I will explain a little later on: it has prostrate stems which creep along the ground, as shown in the illustration, and root every now and again as they proceed, somewhat after the same fashion as strawberry-runners. Like all other clovers, it has trefoil leaves, each of the three leaflets in which is usually marked with a curved spot in the centre resembling a horse-shoe. But it is the flower-heads with which I am here particularly concerned. These are raised on long, erect, leafless stems, each of which bears on its summit a globular head of little white peaflowers, often delicately tinged with pink or salmon. The flowers are thus lifted to a considerable height, because this clover grows, as a rule, among rather tall grasses, and so tries to push up its blossoms to a height where they may receive the polite attentions of passing insects.
