The other consideration, to which, in my opinion, sufficient attention has not been paid, is whether the various colors are used appropriately. To prove the existence of a well-developed color sense from monuments, it is not enough to show that certain colors were used; it must be shown that they were used appropriately. Even in the case of Egyptian art, one reads of statues of human figures with blue hair, and in the case of early Greek art, the inappropriate use of one color, blue appears to have been very common.
I am informed by Mr. E. E. Sikes, to whom I am glad of this opportunity of expressing my thanks for much kind advice, that in the Acropolis at Athens, such examples of coloration are to be seen as a blue bull, a blue horse, a man with blue hair, beard and mustache, these probably dating from 600 B. C, certainly later than the time of Homer.[1] When such examples of eccentric coloration in blue are found associated with the defect in nomenclature for the same color, it is difficult to believe that the sense for this color can have been as highly developed in those times as it is among civilized races at the present day. The whole subject of the use of color in ancient monuments, in its bearing on color vision, requires a more thorough investigation than it has hitherto received.
Another line of objection to the views of Gladstone and Geiger, which has already been mentioned as having been taken up by Grant Allen, is derived from the high degree of development of the color sense in many of the lower animals, and especially in insects and birds. To many of those who have taken part in the controversy, this objection appears to have been regarded as conclusive. A well-developed color sense in any one branch of the animal kingdom does not, however, necessarily imply the existence of the same in other, even if higher, forms. We have many instances of the independent development of closely similar mechanisms in very widely separated branches of the animal kingdom, and there is nothing improbable in the view that this may have been so in the case of the color sense. If the color sense were found to be highly developed in mammals, the fact would naturally have a closer bearing on the color sense of man than has the presence of a similar development in birds. The evidence, however, of such development in mammals is very defective. Graber,[2] who has carried out the most comprehensive investigations of the color sense in different branches of the animal kingdom, obtained much less definite evidence from mammals than from other animals, and altogether failed to obtain evidence in the case of some species. Again, if the anthropoid apes were found to have a well-developed color sense, the fact would have
