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Darwin's New Work.*

THIS volume like most of the later work given to the world by Mr. Darwin is made up of a careful record of experiments, heralded by a few pages of introduction, with here and there a summarized statement of the facts reached, and an occasional deduction or generalization. He usually, however, lays before his reader the facts which he has observed -the failures often, as well as the successes -and leaves the deduction to make itself. He tries to give to his reader the data upon which to found a theory, rather than the theory itself. His clear and logical mind organizes the material thus gathered and presented, but there is no suspicion of

special pleading, no personal color even, in the simple, lucid presentation of facts. Mr. Darwin is in no sense a fighter, he is only the cause of fighting in others. These investigations of his bring to light many curious facts which have escaped the notice of all the observers who went before him. Movements in the germination and fecundation of plants were noticed and recorded by other observers long ago ; some of the latter are almost too wonderful to be believed, as in the case of valisenria spiralis; and Mr. Darwin himself has recorded many wonderful instances of what looks like voluntary and intelligent movement in his books entitled, "Orchids Fertilized by Insects," "Insectivorous Plants," and "Climbing Plants."

This new volume covers more general ground and serves to bring all these apparent exceptions into harmonious relation with vegetable physiology in general. The movement of plants instead of being confined to certain times or particular families, is shown to be universal, so long as they are growing. Each twig and root in its upward and downward progress is found when not restrained to describe an irregular ellipse. The causes which induce these  movements are gravity, heat, light, moisture, and pressure, either separately or in combination. These causes produce in the plant various cellular changes. In some cases the cells on one side of a leaf or stem become turgid and on the other depleted, whence a bending of course ensues; unequal evaporation or unbalanced growth will produce the same effect, sometimes rapidly, and again slowly, sometimes permanently and again temporarily. The last chapter contains a summary of the whole volume, and this together with the introduction, and possibly a little reading here and there in the coarser type will give to any but a technical reader a satisfactory idea of the entire work.

The most remarkable conclusion from his researches Mr. Darwin reserves till his last page, and this is the presence in vegetable organisms of something akin to the brain o the lower animals. The tip of the radical, he states, appears to possess a sensitiveness to impressions, and the power of directing the movements of adjoining parts.