Whether the organism stands at rest and life comes to it on the material currents of the winds and waters, or in the vibratory energy of the aether; or, again, whether with restless craving it hurries hither and thither in search of it, matters nothing.  The one principle—­the accelerative law which is the law of the organic—­urges all alike onward to development, reproduction and death.  But although the individual dies death is not the end; for life is a rhythmic phenomenon.  Through the passing ages the waves of life persist:  waves which change in their form and in the frequency to which they are attuned from one geologic period to the next, but which still ever persist and still ever increase.  And in the end the organism outlasts the generations of the hills.

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THE BRIGHT COLOURS OF ALPINE FLOWERS [1]

IT is admitted by all observers that many species of flowering plants growing on the higher alps of mountainous regions display a more vivid and richer colour in their bloom than is displayed in the same species growing in the valleys.  That this is actually the case, and not merely an effect produced upon the observer by the scant foliage rendering the bloom more conspicuous, has been shown by comparative microscopic examination of the petals of species growing on the heights and in the valleys.  Such examination has revealed that in many cases pigment granules are more numerous in the individuals growing at the higher altitudes.  The difference is specially marked in Myosotis sylvatica, Campanula rotundifolia, Ranunculus sylvaticus, Galium cruciatum, and others.  It is less marked in the case of Thymus serpyllum and Geranium sylvaticum; while in Rosa alpina and Erigeron alpinus no difference is observable.[2]

In the following cases a difference of intensity of colour is, according to Kerner ("Pflanzenleben,” 11. 504), especially noticeable:—­ Agrostemma githago, Campanula

[1] Proc.  Royal Dublin Society, 1893.

[2] G. Bonnier, quoted by De Varigny, Experimental Evolution, p. 55.

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pusilla, Dianthus inodorus (silvestris), Gypsophila repens, Lotus corniculatus, Saponaria ocymoides, Satureja hortensis, Taraxacumm officinale, Vicia cracca, and Vicia sepium._

To my own observation this beautiful phenomenon has always appeared most obvious and impressive.  It appears to have struck many unprofessional observers.  Helmholtz offers the explanation that the vivid colours are the result of the brighter sunlight of the heights.  It has been said, too, that they are the direct chemical effects of a more highly ozonized atmosphere.  The latter explanation I am unable to refer to its author.  The following pages contain a suggestion on the matter, which occurred to me while touring, along with Henry H. Dixon, in the Linthal district of Switzerland last summer.[1]