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large flowers, sacrificing its fruit; but you expect that its line of improvement will be in the direction of large and delicious pulp. If improved flowers are produced, it is a very rare exception.
Let us take another illustration, nearer still; take the potato and tomato. You know very well that they are botanic brothers. Even the potato-bugs know this, because they will eat tomato-vines when they are driven to it. What is the line of development in each ? You know the potato has potato-balls on the top of the vines; and they correspond exactly to tomatoes in structure: they are the same thing botanically as the tomato. The potato has been carried over a great portion of the globe. See the number of varieties that have been produced in different parts of the world. If you take ten thousand seeds of the potato, and plant them, what do you expect to produce? Do you expect to produce plants that will bear large, edible fruit on the top? No. You expect that the plant will vary in the line of its tubers always. We have to-day hundreds of varieties of the potato, and there is no end to the number of kinds that you can produce; but the plant always develops in the same line. How is it with the tomato? If you plant its seeds, you expect that the fruit on the top of the plant will vary. Certainly. Nobody ever heard of a tomato varying, except in the line of that fruit on the top: that fruit is its utility. You have the potato varying in the line of its underground stems or tubers: that is its utility. I might go on illustrating this principle, and give example after example of plants that are close together botanically, developing in different lines. Those who first cultivated these plants did not know what the leading idea of the plant was. They saw this beautiful flower, and they said, “ Let us save it,” because all men, even savages, have an appreciation of the beautiful; and they began to cultivate it, and it began to develop in its own line. Then the fruitbearing plant attracted attention, and secured cultivation for its utility; and it developed in its line. And the result is what we see in beautiful flowers and delicious fruits.
Now, how far can this be carried ? This variation is first for the benefit of the plant. It is for the purpose of adapting the plant to the earth: that seems to be the primary purpose of this variation. I am speaking as though there
were a purpose in it. If
do not believe in such purpose, it is no matter; but I use such language because it is convenient, and I have been accustomed to it. I say this seems to be the first object, to preserve the species, and adapt it to all parts of the earth. Let us see, then, in regard to the extent to which this principle can be carried. You will find that this principle of variation can be carried so far as to utterly defeat its end, if you suppose that the distribution and preservation of the plant is its object. And this is a point to which I wish to direct your special attention, to see if we can reach a principle in it. I hold in my hand a rose (and I am glad they brought in such a rose as this): it is called a double rose; but in this rose I can see stamens and pistils. That rose would probably reproduce its kind from seed, because it has the organs which are essential for reproduction. There are roses in which you shall not find a single stamen or pistil. They are all unrolled, all developed (if I may use that term “developed” in this connection), — they are all unrolled, and made into these flower-leaves. And you will find other plants in the same condition. All peonies are not double; but some are so double that they have no stamens or pistils, and never produce any seeds. We call the snowball double ; but it has quite different characteristics from the rose. In its wild state it has a circle of flowers on the outside which never produce fruit; but it has flowers in the centre which produce fruit. By cultivation they lose their stamens and pistils, and they become large, and give us beautiful white bunches of flowers; but they cannot produce fruit. What does this show? It shows that this principle of variation which begins far back in the life of the plant, — begins for the benefit of the species, — finally ends in what would seem to be the destruction of the species, because, when you carry this variation so far as to destroy the stamens and pistils, just that moment you have destroyed the plant, so far as the seed is concerned: you have stopped all that machinery for the continuance of the species through the seed.
Let us look at that a moment, and see exactly what it leads to. What has been the result of this wiping out of the seed-producing power here? The result has been increased beauty. You have gone on developing this flower in the line of beauty, its utility gradually giving way, until
by and by it all disappears, and the plant appears before you simply as an object of beauty, having no power to reproduce its kind. Having lost this power, it is no benefit to its species. It is a draft upon this plant, and therefore it is an injury to the individual. So far as the plant-life is concerned, the machinery is all out of order, because here we have material taken out of the wood and leaf, and put into this form, — of no sort of use to the plant itself, of no sort of use to the species, because it cannot produce seed.
But did you ever see any plant whose flower could be made perfectly double, that could not be propagated in other ways than by seed — by root, by stem, by bud, or graft. You have annual plants that you call double; but, when you examine them, you will find that they are not perfectly double. Take those plants you can carry along on the line of beauty until you have completely wiped out the stamens and pistils, and you may be sure, that, when you have done that, you have gone as far as you can go; and, if
want to propagate such plants, it must be by some of the methods I have mentioned, -by budding, layering, grafting, or some process, other than the seed.
Take an apple, for instance. What is the use of its pulp? Every one says at once, " The soft part of the apple is to cover the seed.” Certainly. But, then, just look at our apple-trees, and see how large the delicious pulp is, compared with what is needed to protect the seed. And do you not know, also, that, when apples and pears become so large and delicious, their seeds are not as large or fully developed, and very likely there may be less of them? And so of the grape. How far can this increase of pulp be carried? You know that some oranges have no seeds. I presume we should find plenty of seeds in these oranges. But some of the nicest oranges from Fayal, and other places, have not a seed in them. The process in them has been carried so far, that you have simply a great globe of delicious pulp, with hardly a vestige of seed. In some grapes this process has been carried so far, that you have a mass of delicious fruit, and not a seed in it. You have carried this process, in that sort, as far as you can carry it. Here, for instance, is a Fayal orange-tree, loaded with delicious fruit: what does it mean? It began by meaning good to its species, as well as to the animal kingdom.
Does it mean that now? Not at all. There is not a seed in the fruit: therefore the fruit cannot propagate its kind ; and every single orange takes material out of the wood and leaf, that is, it takes the material that would have gone to build up the individual plant. Therefore this process is an injury to the individual, and it is no benefit to the species.
You see, then, that we can divide all these plants that we talk about here, day after day, into these two great classes. In many of them you can run the idea of beauty until the power of reproducing their kind is lost; or you can run the idea of utility until the same power is lost. But what do we gain in all this? In every case we gain that which man wants, that which is the prime object for him. We get the most beautiful flowers, and we get luscious fruit, without seed, and we have given to us means by which we can propagate both of them. Does not this look very much as though there was a purpose here? a purpose that takes care of the plant while it is wild. But, the moment the plant passes into the hands of intelligent man, it manifests this law, by which it can be developed so that it cannot take care of itself; but, being taken care of by man, it yields to him a hundred-fold what it could have yielded when it was left to take care of itself.
Now I come to a point which would lead me to a path which I do not propose to tread, which will be pursued by the lecturer tomorrow night. But I must come up to it. You will observe, that, so far, I have spoken of this variation as though, once begun, it was carried on in that particular line by that individual in which it appeared. Now there comes in another principle, which is a very important one, and which, I have no doubt, Professor Goodale will very fully develop tomorrow night; and that is this, — going down to the lowest forms of plants, we find something equivalent to sexual relation. Everybody understands there is sex in the higher plants. Linnæus, who was a great naturalist, showed his intuition, his keenness of insight, when he called the lower plants cryptogamous: that means the marriage-relation concealed. Although he could not point out, as we can, the sexual relation of these lower plants, he still believed in it, as is shown by his application of this word. Even in these low plants, where they are made up of a few cells, there is a
in their young
joining together from time to time of those cells. Why is it, that, for instance, in the flower of the apple-tree there should come up a central organ that holds the seeds, and then, when the time comes for those seeds to be fertilized, there should appear another organ, right by the side of it, in the same flower, bearing another kind of cell, — the pollen that must fertilize each seed before it can grow? It is a wonderful structure, as all of us are aware. But see what power this structure gives us. Here we have one plant developed in one line, and another in another. By taking some of those cells of pollen, and passing them to the pistil of the other plant, we are able to get the characteristics of the two plants
What a wonderful power that gives us ! We see among the higher animals that their association and parental relation is a source of great enjoyment, as, in the human family, it is the source of the greatest enjoyment, the highest and noblest we have. But why should sexual relation prevail among the plants? We have one characteristic in a plant, and we want another. We might go on, and develop that indefinitely, and never get the one we want. But, just as soon as we find what we can do by taking the pollen of one plant and carrying it to another, we seek for a plant which has the characteristic we wish, to combine with the one we have. We fertilize one plant with the pollen of the other; and then, by careful selection and cultivation, we are likely to get just the qualities combined that we want.
In my judgment, there are very many agencies that have an influence upon the germs of our seeds when they are formed, that we do not now understand. The fact that seeds that look just alike, and were raised in the same place, give us much different results, is not always owing to the soil. I have no doubt that those germs are wonderfully sensitive, far beyond any thing we have ever dreamed of. There are many things in our experiments that lead me to suppose this. I believe, also, that the action of this pollen is very much more far-reaching than has generally been supposed.
I have here some specimens of corn which I have been experimenting upon this year; and the first specimens I show you will illustrate the point which I made in regard to the variation of plants. This is the small rice-corn. These ears which you see in my hand — three white and three red ones