The principal interest of this make-believe consciousness is that it is considered by many to be an essential ingredient of AEsthetic feeling. A work of art is said to have its effect through its tendency to arouse in us a make-believe acceptance of the scene or motive presented, while it nevertheless remains contrasted with the realities of our lives. If this be true, the interesting question arises how far the animals also have the germs of AEsthetic feeling in their make-believe situations. Does the female pea-fowl consider the male bird, with all his display of colour and movement, a beautiful object? And does the animal companion say: How beautiful! when his friend in the sport makes a fine feint, and comes up serene with the knowing look, which the human on-looker can not fail to understand? In some cases, at any rate, we should have to reply to this question affirmatively, if we considered make-believe the essential thing in aesthetic enjoyment. _Theories of Animal Play._--The question of the meaning and value of play to the animals has had very enlightening discussion of late. There are two principal theories now advocated. I. The older theory considered play simply the discharge of surplus nerve force in the animal's organism. He was supposed to play when he felt fresh and vigorous. The horse is "skittish" and playful in the morning, not so much so at night. The dogs lie down and rest when they are tired, having used up their surplus energies. This is called the Surplus-Energy Theory of play. The difficulty with this theory is that it is not adequate to explain any of the characteristics of play which have been given above. Why should play be instinctive in its forms, showing certain complex and ingrained channels of expression, if it were merely the discharge of surplus force? We are more lively in the morning, but that does not explain our liking and indulging in certain sorts of complex games at all hours. Moreover, animals and children will continue to play when greatly fatigued. A dog, for example, which seems absolutely "used up," can not resist the renewed solicitations of his friends to continue the chase. Furthermore, why is it that plays are characteristic of species, different kinds of animals having plays quite peculiar to themselves? It is difficult to see how this could have come about unless there had been some deeper-going reason in accordance with which each species has learned the particular forms of sport in which it indulges.