First of all, on grounds of psychology, I see no reason to doubt that the receptual intelligence of an already intelligent and highly social species of anthropoid ape would admit of considerable advance upon that of any existing species without the aid of articulation—social habits making all the difference as to the development of sign-making with its consequent reaction upon mental development. Next, for these early stages of advance, I do not see that articulate sign-making would have conferred any considerable advantage over a further development of the more natural systems. For, so long as the only co-operation required had reference to comparatively simple actions, the language of tone and gesture would have admitted of sufficient development to have met all requirements. Lastly, if we take the growing child as an index of psychogenesis in the race, there can be no doubt that it points to a comparatively late origin of the faculty of articulation. Remembering the general tendency of ontogenesis to foreshorten the history of phylogenesis, it is, I think, most suggestive that—notwithstanding its readiness to imitate, and notwithstanding its being surrounded by spoken language—the infant does not begin to use articulate signs until long after it has been able to express many of its receptual ideas in the language of tone and gesture. It will be remembered that I have already laid stress upon the astonishing degree of elaboration which this form of language undergoes in the case of children who are late in beginning to speak (see pp. 220). And although it might be scarcely justifiable to take these cases as possibly representative of the semiotic language of _Homo alalus_ (seeing that the child of to-day inherits the cerebrum of _Homo sapiens_); still I think it is no less certain that we should err on the opposite side, if we were to take the case of a child who is precocious in the matter of speech as a fair index of the grade of mental evolution at the time when articulation first began in the race (seeing that the history of the latter is probably foreshortened in that of the former). Yet, even if we were to do this, for the sake of argument, the result would still be most strongly to indicate that long before our remote ancestors were able to use articulate speech, they were immeasurably in advance of all existing brutes in their semiotic use of tone and gesture. For even a precocious child does not begin to make any considerable use of words as signs until it is well on into its second year, while usually this stage is not reached until the third. And, at whatever age it is reached, the general intelligence of the child is not only much in advance of that of any existing brute, but the direction in which this advance is most conspicuous is just the direction where, in the present connection, it is most suggestive—namely, in that of natural sign-making by tone and gesture. * * * * *