Among insects it scarcely appears, nor should we expect that there would be any peculiarly marked predilection or aversion for red. Cockerell and F. W. Anderson, from observations in various parts of the United States, believe that yellow (_i. e._, the brightest color) is the most attractive to insects, and the former doubts whether insects can distinguish red from yellow. Among the higher animals, and even among fishes and birds, there is not only a color sense, but a highly emotionalized color sense, and red appears to be usually the color that arouses the emotion. There is a proverb, ‘Women and mackerel are caught by red,’ and perch is also said to be caught by red bait. Sparrows appear to be repelled by red; the case is reported of a hen sparrow, kept in captivity for ten years, which though otherwise a fearless bird ‘would on seeing scarlet show painful signs of distress and faint away.’ The lady who records this observation has noted the same repugnance to red, though in a less marked degree, in other sparrows, one of which showed a predilection for blue objects, and she remarks that when feeding outdoor sparrows from the window they flew away when she wore a red jacket, while a blue jacket inspired them with confidence; other birds, she found, except a cockatoo, were unaffected by colors. Red, it is well known, is very obnoxious to turkey cocks, while the fury aroused in various quadrupeds by red was known at a very early period; Seneca referred to it in the case of the bull, the most familiar example; it is seen in buffaloes, sometimes in horses, and also, it is said, in the hippopotamus. The phenomena of color aversion and color predilection among insects may possibly be in some degree a matter of physical sensibility, varying according to the creature’s tissues, habitat and needs, but as we approach the vertebrates and especially the mammals there can be little doubt that it is mainly a matter of environment and association; in other words, that it is accounted for by the color of food, the color of blood and the color of the chief secondary sexual characters. Let us, however, confine ourselves to man, and consider what are the chief colored objects that are of most vital concern to the human and most closely allied species. One of the earliest groups of such objects--some would say the most important group in this connection--is that of ripe fruits. Certainly among the frugivorous apes and among many races of primitive man, the color of fruits must be a powerful factor in developing a sensibility for red rays, and in associating such sensibility with emotional satisfaction. The color of fruits is most generally red, orange or purple, and since purple is largely made up of red, it is clear that the influence of fruits will almost exclusively bear on the rays of long wave-length. We may reasonably suppose that the search for fruits acted as an important factor in the development of a special sensibility for red.