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emplified in a fresh volume, in which the veteran was materially assisted by his son, Mr. Francis Darwin. Its object was to describe and connect together several large classes of movements, common to almost all plants. The surprising fact was established, that all the parts or organs of plants, whilst they continue to grow, are continually revolving, or circumnutating as Darwin called it. This movement commences even before the young seedling has broken through the ground. The combination of this with the effects of gravity and light explains countless phenomena in the life of plants. The tip of the rootlet is thus enabled to penetrate the ground, and it is proved to be more sensitive than the most delicate tendril. Movement goes on through all stages of life. Every growing shoot of a great tree is continually describing small ellipses; the tip of every rootlet endeavours to do the same. changes of position of leaves and of climbing plants, and the sleep of leaves are all brought under this great principle of circumnutation. It is impossible in reading the book not to be struck with the great resemblance between the movements of plants and many of the actions performed unconsciously by the lower animals. "With plants an astonishingly small stimulus suffices, and, even with allied plants, one may be highly sensitive to the slightest continued pressure, and another highly sensitive to a slight momentary touch. The habit of moving at certain periods is inherited both by plants and animals, and several other points of similitude have been specified. But the most striking resemblance is the localisation of their sensitiveness, and the transmission of an influence from the excited part to another which consequently moves. Yet plants do not

of course possess nerves or a central nervous system; and we may infer that with animals such structures serve only for the more perfect transmission of impressions, and for the more complete intercommunication of the several parts."

Here we see how much light may be thrown on animal structures and functions by vegetable physiology. We learn to limit our ideas of the superiority of animals by discovering how much of what we consider peculiar to them is found in plants. We appreciate the unity of biology, indivisible without injury to our knowledge of its parts. No structure in plants appears more wonderful, as Darwin describes it, than the tip of the rootlet of a seedling. It is impressed by and transmits influences of pressure, injury, moisture, light, and gravity to other parts, and determines the course pursued by the rootlet in penetrating the ground. "It is hardly an exaggeration to say that the tip of the radicle thus endowed, and having the power of directing the movements of the adjoining parts, acts like the brain of one of the lower animals;" and the brain of Charles Darwin, in working out this acquisition of knowledge for mankind, has added a new department to vegetable physiology and to biology.

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CHAPTER X.

N his later years honours poured thick upon Darwin. In 1871 he received the Prussian order of knighthood "For Merit"; and was elected a corresponding member of the Austrian Academy of Sciences. In 1877 Cambridge University, making an exception to its custom of not conferring honorary degrees on its members, gave him the LL.D. and an ovation, when the kindly eyes of the venerable naturalist beamed upon the monkey-figure dangled by undergraduates before him from the galleries, in addition to a solitary link of a huge chain, no doubt representing "the missing link." In 1878 the honour, long withheld, and certainly unsought, of being elected a corresponding member of the Paris Academy of Sciences in the section of Zoology, was his; and that tardy body recognised late the man whose supremacy in science it had done nothing either to foster or to approve. In 1879 the Baly Medal of the London College of Physicians was awarded to him.

After the Cambridge celebration a subscription was raised to obtain a portrait of the veteran evolutionist, which was executed by Mr. W. B. Richmond, and now adorns the Philosophical Library of the New Museums at Cambridge. Later, yet another portrait-the finest

in his own and many others' belief-was painted by Mr. John Collier, and presented to the Linnean Society, which will always be associated with the first announcement of Darwin's main theory, as well as with many others of his scientific discoveries.

Professor Haeckel has given the following charming description of Darwin and his home surroundings in his later years: "In Darwin's own carriage, which he had thoughtfully sent for my convenience to the railway station, I drove, one sunny morning in October, through the graceful, hilly landscape of Kent, that with the chequered foliage of its woods, with its stretches of purple heath, yellow broom, and evergreen oaks, was arrayed in its fairest autumnal dress. As the carriage drew up in front of Darwin's pleasant country house, clad in a vesture of ivy and embowered in elms, there stepped out to meet me from the shady porch, overgrown with creeping plants, the great naturalist himself, a tall and venerable figure, with the broad shoulders of an Atlas supporting a world of thought, his Jupiter-like forehead highly and broadly arched, as in the case of Goethe, and deeply furrowed with the plough of mental labour; his kindly, mild eyes looking forth under the shadow of prominent brows; his amiable mouth surrounded by a copious silver-white beard. The cordial, prepossessing expression of the whole face, the gentle, mild voice, the slow, deliberate utterance, the natural and naive train of ideas which marked his conversation, captivated my whole heart in the first hour of our meeting, just as his great work had formerly, on my first reading it, taken my whole understanding by storm. I

fancied a lofty world-sage out of Hellenic antiquity-a Socrates or Aristotle-stood before me."

The well-known botanist, Alphonse de Candolle, thus describes a visit to Down :

"I longed to converse once more with Darwin, whom I had seen in 1839, and with whom I kept up a most interesting correspondence. It was on a fine autumn morning in 1880 that I arrived at Orpington station, where my illustrious friend's break met me. I will not here speak of the kind reception given to me at Down, and of the pleasure I felt in chatting familiarly with Mr. and Mrs. Darwin and their son Francis. I note only that Darwin at seventy was more animated and appeared happier than when I had seen him forty-one years before. His eye was bright and his expression cheerful, whilst his photographs show rather the shape of his head, like that of an ancient philosopher. His varied, frank, gracious conversation, entirely that of a gentleman, reminded me of that of Oxford and Cambridge savants. The general tone was like his books, as is the case with sincere men, devoid of every trace of charlatanism. He expressed himself in English easily understood by a foreigner, more like that of Bulwer or Macaulay, than that of Dickens or Carlyle. I asked him for news of the committee, of which he was a member, for reforming English spelling, and when I said that moderate changes would be best received by the public, he laughingly said, 'As for myself, of course, I am for the most radical changes.' We were more in accord on another point, that a man of science, even

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