VII. MISCELLANEOUS. Dr. G. J. Romanes sends the following : I should like to make a few explanations in reply to those parts of Mr. Whittaker's review, in MIND XXXIV., of my recently published work, Mental Evolution in Animals, which are of a critical nature. Touching my definition of Instinct, it is enough to say that I recognise the validity of his criticism. Instead of saying that 'instinct is reflex action into which there is imported the element of consciousness,' I ought in this passage to have defined my view more closely and substituted for the word 'consciousness' the word 'perception'. But, as Mr. "Whittaker virtually shows, my meaning in this matter was not left obscure ; for, as he observes, " This is now explained to mean that, while ' a stimulus which evokes a reflex action is at most a sensation,' on the other hand, ' a stimulus which evokes an instinctive action is a perception ' ". In Mr. "Whittaker's opinion my "treatment of the fundamental question of the relation of Mind and Body can hardly be described as satisfactory ". This, perhaps, is scarcely surprising, in view of the fact that I do not treat of this question at all. Originally I had written a long chapter upon it, which was intended to succeed the chapter on ' The Physical Basis of Mind '. This, however, I afterwards published as a separate essay in The Nineteenth Century. In that essay 'the opposition between subject and object ' was stated with so much emphasis that in subsequent parts of the book I did not recur to the matter. After having withdrawn this chapter from the book, however, it might perhaps have been better if I had quoted portions of it instead of having merely referred to it in a foot-note. Never- theless, if my reviewer had consulted the reference, I do not think he could have supposed that I experience any dimness of vision upon this topic. Still less could he have supposed that I "appear to think that the occur- rence of consciousness is somehow explained if it can be shown to arise when there is an increase in the time taken up by the transmission of a stimulus :) . Indeed, I cannot understand how any reader of my book, even in the absence of the chapter on ' Mind and Body,' could place this inter- pretation upon any of its passages. I have merely stated the observable and demonstrable fact that consciousness only arises when there is a com- parative delay in the essential response of a nerve-centre to a stimulus. I have nowhere insinuated that this fact serves to convey any explanation of the occurrence of consciousness. The only remaining criticism which I have to notice is that which has reference to my diagrammatic representation of the probable course of mental evolution. My critic observes : "The branching structure can only represent the division of a .single mind at each of its stages into faculties, not the divergence of different types of mind. Nothing is said as to the possibility that at the same level of general intelligence there may be essentially different mental types dependent, for example, on different degrees of acuteness of the senses, and different ratios of their degrees of acuteness to one another. . . . The evolution of existing types of animal intelligence, as well as existing types of animal organisation, ought to be shown by a genealogical tree." K ow, I do not dispute that it would be desirable to form such a genealogical tree of existing types of animal in- telligence, if the formation of such a tree were in the nature of the case possible. But I do not consider that in the nature of the case this is pos- sible. Our means of investigation in comparative psychology being
