chiefly in vogue in vineries, and with wall fruit, is to bend and twist the branches into as many contortions as possible with the same object. Another, again, is to turn the plants when the wood is ripe into the frost, and to keep them there a long time. All these plans are more or less efficacious. The rationale of everyone of them is the mutilation, or starving, or weakening of the tree, in order to make it fruitful. If we adopt the opposite course what is the result? Our camellias, which have set hundreds of bloom buds in the autumn, will discard them rapidly if we stimulate the plant by feeding it, or giving it heat sufficient to induce a winter growth. The buds will fall off in myriads, and leaves and branches sprout out everywhere. The same is notoriously the case with peaches; the fruit that best tests the gardener's skill and patience. Orchids refuse to bloom if supplied with food and moisture, while if allowed to dry and shrivel away to the point of death they will throw out spikes of bloom; the same is true of cacti, and in fact of all kinds of plants, I know, in a greater or less degree. But we may go further. The double flower is a distorted form produced by cultivation, i.e., by abundant food and decent conditions. In the double flower the reproductive organs are altered, and often absent, and no seed is produced. Now it is curious that one of the first effects of taking our wild flowers into the green-house is to make them grow double, and cease to bear seed. Thus it is that our double garden daisy grew out of the wild daisy, and the chrysanthemum out of the ox-eye; and where the effect is not great enough to affect the flower it often affects the fruit. The coarse little shrivelled melons, cucumbers, and oranges, growing on wounded, dried up, and paralyzed branches, are full of seed; while the fleshy giants that have been well tended and fed have hardly any seed at all in them. The same is the case with grapes, and the small grape that forms the domestic currant. The green-house is notoriously a bad place to ripen seed in, and so is the highly cultivated garden. The wild kale that grows on wild exposed rocks has a few ragged hard leaves, and a thick panacle of seed; while the cabbages in our gardens hardly bear any at all.

Mr. Darwin has cited one or two cases on the other side, of which the most striking is the case of the cereals which are notoriously heavily weighted with grain, and this chiefly due, he contends, to the heavy manuring and careful cultivation they have been subject to. But the cereals are cases that I should quote to prove my own position; with highly cultivated, thickly planted wheat, there must be a terrible struggle going on for light and air with the leaves, and for food with the interlaced and thickly tangled roots of a myriad of neighbours which press

upon each individual on every side, and cause the stubble to become very matted, a very different condition from that of the wild wheat of Thibet. The same argument applies to rice, and to other crops which are planted thickly, and which, in the phraseology of farmers, exhaust the land. So far as my experience goes, the evidence of cultivated plants is decidedly overwhelming against Mr. Darwin, and in favour of my position that the weak, the ill-fed, and the pinched, are the most fertile. Our means of testing wild plants is not so great. A correspondent of Nature calls attention to a fact which strongly corroborates me. He refers to the notorious fact that the money worts (he might have quoted the strawberry, the ivy, or any other creeping plant equally well) will hardly bloom at all if allowed to sprawl in all directions, taking root, and therefore nourishment at every joint, while if the suckers are spread out on slabs of stone so that the whole plant has to be nourished from the mother root, it will bear abundantly. Among weeds like groundsel and dandelion, the most abundant and fertile seed is scattered by those living on the edges of the common, weakly plants rooted among stones, and in a poor soil. Beech trees growing in rich pastures ripen little mast, the husks having no kernels. Oaks and firs bear the most fruit on rugged exposed situations, or where the subsoil is poor and gravelly. So that we may infer that what is true of cultivated plants is equally true of wild ones.

Mr. Doubleday in the postscript to his second edition quotes two facts which have an analogous bearing with the preceding, namely, that grafts from a dying tree strike with far more certainty than those from a tree in full vigour, and that seeds which have been kept some time germinate in the majority of cases far more surely than those that are recent. He also says that pear and apple trees bear most profusely just before they die, and that after severe winters, of which that of 1836 and 1837 was a notorious example, grass and other vegetables grow at an immensely increased rate. All these facts point in one direction only.

Let us now turn from the vegetable world to the animal. Stockkeepers and breeders have accumulated much sound experience on the subject, which corroborates that of gardeners in regard to plants. It is a golden rule with them to keep their animals weak, and in a state of depletion, if they wish them to breed freely. Pure breeds are seldom very fruitful; they are notoriously pampered and highly fed, and when prize shorthorns and southdowns are turned into coarse pastures where kyloes and mountain sheep might feel it a luxury to live, but where their round sides are speedily denuded of flesh, they breed

much more readily; the same is true of horses. Mr. Doubleday quotes the case of a highly bred blood mare, which for a length of time appeared to be incurably barren, and from which the owner naturally desired to obtain a breed, rendered fertile, and ultimately the dam of a numerous progeny, by being literally put to the plough and cart, fed sparingly, and worked down to a state of extreme leanness and temporary exhaustion. He goes on to say in the sheep, however, this principle of increase or decrease is most nicely developed. It is invariably found that if over-fed sterility is the consequence. On the other hand, in accordance with the leanness of the animal a produce of one, two, or three lambs takes place. Upon their knowledge of this fact the improvers of the breed of this animal are accustomed to act. In order to afford the best chance of a perfect animal it is believed that a produce of one lamb at a birth is desirable, and this the breeders of sheep contrive to secure by apportioning the food of the ewe to such a nicety that, avoiding sterility on the one hand, and a double or triple birth on the other, a single lamb is almost invariably the offspring of the animal so limited. It is also a fact known to stock-farmers that during severe seasons, when food is scarce, most lambs are on the average produced. Mild open winters are not favourable to the increase of sheep, because during such winters grass is plentiful. Farriers, I am told, very often bleed horses and cattle which are stubbornly sterile to induce fertility.

If we turn from domestic animals to semi-wild and only partially reclaimed ones we find that the same rule applies. I prefer to quote directly from Mr. Darwin, who has on this branch of the inquiry furnished us, as he so often does, with the best materials for an answer to himself. In this case he also completely answers an opponent of mine in Nature, Dr. Tait, who accuses me of misreading the rationale of the evidence. The most remarkable cases, however, are afforded by animals kept in their native country, which, although perfectly tamed, quite healthy, and allowed some freedom, are absolutely incapable of breeding." Rengger, who in Paraguay particularly attended to this subject, specifies six quadrupeds in this condition, and he mentions two or three others which most rarely breed. Mr. Bates, in his admirable work on the Amazons, strongly insists on similar cases, and he remarks that the fact of thoroughly tamed wild animals and birds not breeding when kept by the Indians cannot be wholly accounted for by their negligence or indifference, for the turkey is valued by them, and the fowl has been adopted by the remotest tribes. In almost every part of the world, for instance, in the interior of Africa, and in several of the Polynesian islands, the natives are extremely fond of

taming the indigenous quadrupeds and birds, but they rarely or never succeed in getting them to breed." Mr. Darwin continues his illustrations of this fact through many closely packed pages, after which he adds the following commentary (see "Variation of Animals and Plants under Domestication"), vol. ii, p. 158: "We feel at first naturally inclined to attribute the result to loss of health, or at least to loss of vigour; but this view can hardly be admitted, when we reflect how healthy, long-lived and vigorous, many animals are under captivity, such as parrots, and hawks when used for hawking, chetahs when used for hunting, and elephants. The reproductive organs themselves are not diseased, and the diseases from which animals in menageries usually perish, are not those which in any way affect their fertility. No domestic animal is more subject to disease than the sheep, yet it is remarkably fertile." Mr. Darwin, with equal clearness and conclusiveness, decides that this sterility cannot be due to a failure of sexual instincts, change of climate, or want of food, and he concludes that certain changes of habits and of life affect in an inexplicable manner the powers of reproduction. However inexplicable the manner of its operation may be, it seems to me to be impossible to evade the conclusion that the causa causans of the sterility is that I am arguing for in this paper-namely, a more luxurious habit, a more vigorous health, a less precarious existence, induced by the care and attention of domesticators. If we turn from domestic and semi-domestic animals to wild ones, our facts are, of course, less numerous.. Lovers of birds have remarked that after certain severe winters, in which almost all the small birds have been killed off, they have been replaced in a season or two at an astonishing rate by the recuperative vigour of the survivors who have meanwhile been reduced to the verge of death by starvation. Fish that visit the sea, like salmon, do not breed when in high condition, strong with the good living they have enjoyed in salt water, but spawn when they have become meagre and thin after a long sojourn and comparative fast in fresh water. Hibernating animals breed at a season when they are reduced by their long sleep and fast to a very thin and weak condition, and we explain in the same way the much wider fact that it is immediately after the frost has gone, and before the animal world has had time to recover from its hardships that the breeding seasons begins, and so we might continue our examples. Mr. Wallace met my arguments on this point in a very Johnsonian way. I will quote his expression, and the answer I gave him, which will do equally for others who take the same view. He said that when I produced an area in which all the animals were diseased and decrepit, and the strong and healthy ones had disappeared, then he

would credit my theory. I replied that this was no fair statement of my position. That I never maintained that the toothless tiger which cannot seize its prey will be the mother of a numerous progeny. She can do nothing but die, but that as a general law the more weak and ill-fed individuals are more prolific than the strong and well fed.

Mr. Darwin met the arguments of Doubleday and others in a very different manner. He quotes a few instances which seem to tell against them, but he, too, ignores the vastly greater number he had himself quoted on the other side, a portion of which I have given you to-night. The cases he quotes are very few, and they seem to be very unfortunate. The ferret breeds well in confinement, no doubt, but then the ferret is kept in a state of extreme depletion, in order that it may be always hungry and ready to hunt. The domestic fowl, we are told, lays much more abundantly in confinement when it is well cared for than in the wild state. There is an easy answer to this—the eggs of the domestic fowl are abstracted as fast as laid, and every bird-nesting boy knows that if the same plan is adopted with wild birds that they also will continue to lay. In fact, the wilder kinds of fowl, like game, will often make a nest in a wood, or under a hedge, and it is then found that, very like the wild fowl, they lay enough eggs to form a sitting, and no more. The case of the rabbit seems a strong one, but even here it is an undoubted fact that rabbits which breed at a prodigious rate are not those which are found near rich feeding grounds, there they are comparatively sterile. It is on the most barren sand hills near the sea, where food is poor and scarce, that they teem in myriads. The case of the sheep may be met in Mr. Darwin's own words previously quoted, "No domestic animal is more subject to disease than the sheep, yet it is remarkably fertile."

I take it, therefore, that the animal world in general fully corroborates the vegetable world in its evidence on the question at issue. We will now turn to the most conclusive and unanswerable case of man himself. I cannot, in such a question, put man in a kingdom separate to himself, believing as I do that he is influenced by very much the same laws as the vegetable and animal kingdoms, but I detach him in this paper from the rest, simply because our evidence about him is so much more abundant. To begin with individuals. Medical men, upon whose judgment I can thoroughly rely, tell me in confirmation of the dicta of Mr. Doubleday, that it is a recognised law of life with them that semi-convalescent people, and those only just recovering from prostrating diseases like fever plague, etc., are very fertile. It is proverbial with midwives that the same is true of consumptive people.