PDF - Wallace Online

vi COLOURS OF PLANTS 409mena of colour in the organic world. I have shown reasonsfor believing that its presence, in some of its infinitely-variedhues, is more probable than its absence, and that variation ofcolour is an almost necessary concomitant of variation of structure,of development, and of growth. It has also been shownhow colour has been appropriated and modified both in theanimal and vegetable worlds for the advantage of the speciesin a great variety of ways, and that there is no need to callin the aid of any other laws than those of organic developmentand " natural selection " to explain its countless modifications.From the point of view here taken, it seems at onceimprobable and unnecessary that the lower animals shouldhave the same delicate appreciation of the infinite varietyand beauty, of the delicate contrasts and subtle harmonies ofcolour, which are possessed by the more intellectual races ofmankind, since even the lower human races do not possess it.All that seems required in the case of animals is a perceptionof distinctness or contrast of colours; and the dislike of somany creatures to scarlet may perhaps be due to the rarityof that colour in nature, and to the glaring contrast it offersto the sober greens and browns which form the general clothingof the earth's surface, though it may also have a directirritatingeffect on the retina.The general view of the subject now given must convinceus that, so far from colour being as it has sometimes beenthought to be unimportant, it is intimately connected withthe very existence of a large proportion of the species of theanimal and vegetableworlds. The gay colours of the butterflyand of the Alpine flower which it unconsciously fertiliseswhile seeking for its secreted honey, are each beneficial to itspossessor, and have been shown to be dependent on the sameclass of general laws as those which have determined theform, the structure, and the habits of every living thing.The complex laws and unexpected relations which we haveseen to be involved in the production of the special colours offlower, bird, and insect must give them an additional interestfor every thoughtful mind; while the knowledge that, inall probability, each style of coloration, and sometimes thesmallest details, have a meaning and a use must add a newcharm to the study of nature.