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exercise of the powers and faculties they possess, unmixed with any serious dread. There is, in the next place, much evidence to show that violent deaths, if not too prolonged, are painless and easy; even in the case of man, whose nervous system is in all probability much more susceptible to pain than that of most animals. In all cases in which persons have escaped after being seized by a lion or tiger, they declare that they suffered little or no pain, physical or mental. A well-known instance is that of Livingstone, who thus describes his sensations when seized by a lion: "Starting and looking half round, I saw the lion just in the act of springing on me. I was upon a little height; he caught my shoulder as he sprang, and we both came to the ground below together. Growling horribly close to my ear, he shook me as a terrier-dog does a rat. The shock produced a stupor similar to that which seems to be felt by a mouse after the first shake of the cat. It causes a sort of dreaminess, in which there was no sense of pain or feeling of terror, though I was quite conscious of all that was happening. It was like what patients partially under the influence of chloroform describe, who see all the operation, but feel not the knife. This singular condition was not the result of any mental process. The shake annihilated fear, and allowed no sense of horror in looking round at the beast."

This absence of pain is not peculiar to those seized by wild beasts, but is equally produced by any accident which causes a general shock to the system. Mr. Whymper describes an accident to himself during one of his preliminary explorations. of the Matterhorn, when he fell several hundred feet, bounding from rock to rock, till fortunately embedded in a snow-drift near the edge of a tremendous precipice. He declares that while falling and feeling blow after blow, he neither lost consciousness nor suffered pain, merely thinking, calmly, that a few more blows would finish him. We have therefore a right to conclude, that when death follows soon after any great shock it is as easy and painless a death as possible; and this is certainly what happens when an animal is seized by a beast of prey. For the enemy is one which hunts for food, not for pleasure or excitement; and it is doubtful whether any carnivorous animal in a state of nature begins to seek after

prey till driven to do so by hunger. When an animal ist caught, therefore, it is very soon devoured, and thus the first shock is followed by an almost painless death. Neither do those which die of cold or hunger suffer much. Cold is generally severest at night and has a tendency to produce sleep and painless extinction. Hunger, on the other hand, is hardly felt during periods of excitement, and when food is scarce the excitement of seeking for it is at its greatest. It is probable, also, that when hunger presses, most animals will devour anything to stay their hunger, and will die of gradual exhaustion and weakness not necessarily painful, if they do not fall an earlier prey to some enemy or to cold.1

Now let us consider what are the enjoyments of the lives of most animals. As a rule they come into existence at a time of year when food is most plentiful and the climate most suitable, that is in the spring of the temperate zone and at the commencement of the dry season in the tropics. They grow vigorously, being supplied with abundance of food; and when they reach maturity their lives are a continual round of healthy excitement and exercise, alternating with complete repose. The daily search for the daily food employs all their faculties and exercises every organ of their bodies, while this exercise leads to the satisfaction of all their physical needs. In our own case, we can give no more perfect definition of happiness, than this exercise and this satisfaction; and we must therefore conclude that animals, as a rule, enjoy all the happiness of which they are capable. And this normal state of happiness is not alloyed, as with us, by long periods-whole lives often-of poverty or ill-health, and of the unsatisfied longing for pleasures which others enjoy but to which we cannot attain. Illness, and what answers to poverty in animals—continued hunger-are quickly followed by unanticipated and almost painless extinction. Where we err is, in giving to animals feelings and emotions which they do not possess. To us the very sight of blood and of torn or mangled limbs is painful, while the idea of the suffering implied by it

1 The Kestrel, which usually feeds on mice, birds, and frogs, sometimes stays its hunger with earthworms, as do some of the American buzzards. The Honey-buzzard sometimes eats not only earthworms and slugs, but even corn; and the Buteo borealis of North America, whose usual food is small mammals and birds, sometimes eats crayfish.

is heartrending. We have a horror of all violent and sudden death, because we think of the life full of promise cut short, of hopes and expectations unfulfilled, and of the grief of mourning relatives. But all this is quite out of place in the case of animals, for whom a violent and a sudden death is in Thus the poet's picture of

every way the best.

"Nature red in tooth and claw

With ravine"

is a picture the evil of which is read into it by our imaginations, the reality being made up of full and happy lives, usually terminated by the quickest and least painful of deaths.

On the whole, then, we conclude that the popular idea of the struggle for existence entailing misery and pain on the animal world is the very reverse of the truth. What it really brings about, is, the maximum of life and of the enjoyment of life with the minimum of suffering and pain. Given the necessity of death and reproduction-and without these there could have been no progressive development of the organic world,—and it is difficult even to imagine a system by which a greater balance of happiness could have been secured. And this view was evidently that of Darwin himself, who thus concludes his chapter on the struggle for existence: "When we reflect on this struggle, we may console ourselves with the full belief that the war of nature is not incessant, that no fear is felt, that death is generally prompt, and that the vigorous, the healthy, and the happy survive and multiply,"

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CHAPTER III

THE VARIABILITY OF SPECIES IN A STATE OF NATURE

Importance of variability-Popular ideas regarding it-Variability of the lower animals-The variability of insects-Variation among lizards -Variation among birds-Diagrams of bird-variation-Number of varying individuals-Variation in the mammalia-Variation in internal organs-Variations in the skull-Variations in the habits of Animals-The Variability of plants-Species which vary littleConcluding remarks.

THE foundation of the Darwinian theory is the variability of species, and it is quite useless to attempt even to understand that theory, much less to appreciate the completeness of the proof of it, unless we first obtain a clear conception of the nature and extent of this variability. The most frequent and the most misleading of the objections to the efficacy of natural selection arise from ignorance of this subject, an ignorance shared by many naturalists, for it is only since Mr. Darwin has taught us their importance that varieties have been systematically collected and recorded; and even now very few collectors or students bestow upon them the attention they deserve. By the older naturalists, indeed, varietiesespecially if numerous, small, and of frequent occurrencewere looked upon as an unmitigated nuisance, because they rendered it almost impossible to give precise definitions of species, then considered the chief end of systematic natural history. Hence it was the custom to describe what was supposed to be the "typical form" of species, and most collectors were satisfied if they possessed this typical form in their cabinets. Now, however, a collection is valued in proportion as it contains illustrative specimens of all the varieties that occur in each species, and in some cases these

have been carefully described, so that we possess a considerable mass of information on the subject. Utilising this information we will now endeavour to give some idea of the nature and extent of variation in the species of animals and plants.

It is very commonly objected that the widespread and constant variability which is admitted to be a characteristic of domesticated animals and cultivated plants is largely due to the unnatural conditions of their existence, and that we have no proof of any corresponding amount of variation occurring in a state of nature. Wild animals and plants, it is said, are usually stable, and when variations occur these are alleged to be small in amount and to affect superficial characters only; or if larger and more important, to occur so rarely as not to afford any aid in the supposed formation of new species.

This objection, as will be shown, is utterly unfounded; but as it is one which goes to the very root of the problem, it is necessary to enter at some length into the various proofs of variation in a state of nature. This is the more necessary because the materials collected by Mr. Darwin bearing on this question have never been published, and comparatively few of them have been cited in The Origin of Species; while a considerable body of facts has been made known since the publication of the last edition of that work.

Variability of the Lower Animals.

Among the lowest and most ancient marine organisms are the Foraminifera, little masses of living jelly, apparently structureless, but which secrete beautiful shelly coverings, often perfectly symmetrical, as varied in form as those of the mollusca and far more complicated. These have been studied with great care by many eminent naturalists, and the late Dr. W. B. Carpenter in his great work-the Introduction to the Study of the Foraminifera-thus refers to their variability: "There is not a single species of plant or animal of which the range of variation has been studied by the collocation and comparison of so large a number of specimens as have passed under the review of Messrs. Williamson, Parker, Rupert Jones, and myself in our studies of the types of this group;" and he states as the result of this extensive comparison of

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