Finally, if we look at the sense of taste, we find an equally curious agreement between men and insects; for the honey which is stored by the flower for the bee, and by the bee for its own use, is stolen and eaten up by man instead. Hence, when I consider the general continuity of nervous structure throughout the whole animal race, and the exact similarity of the stimulus in each instance, I can hardly doubt that the butterfly really enjoys life somewhat as we enjoy it, though far less vividly. I cannot but think that he finds honey sweet, and perfumes pleasant, and colour attractive; that he feels a lightsome gladness as he flits in the sunshine from flower to flower, and that he knows a faint thrill of pleasure at the sight of his chosen mate. Still more is this belief forced upon me when I recollect that, so far as I can judge, throughout the whole animal world, save only in a few aberrant types, sugar is sweet to taste, and thyme to smell, and song to hear, and sunshine to bask in. Therefore, on the whole, while I admit that the butterfly is mainly an animated puppet, I must qualify my opinion by adding that it is a puppet which, after its vague little fashion, thinks and feels very much as we do. XVII. _THE ORIGIN OF WALNUTS._ Mr. Darwin has devoted no small portion of his valuable life to tracing, in two bulky volumes, the Descent of Man. Yet I suppose it is probable that in our narrow anthropinism we should have refused to listen to him had he given us two volumes instead on the Descent of Walnuts. Viewed as a question merely of biological science, the one subject is just as important as the other. But the old Greek doctrine that 'man is the measure of all things' is strong in us still. We form for ourselves a sort of pre-Copernican universe, in which the world occupies the central point of space, and man occupies the central point of the world. What touches man interests us deeply: what concerns him but slightly we pass over as of no consequence. Nevertheless, even the origin and development of walnuts is a subject upon which we may profitably reflect, not wholly without gratification and interest.