Man { Infant 1 : 22 { Youth 1 : 25 { Adult 1 : 30 { Old 1 : 35 Apes { Saimiri 1 : 22 { Saï 1 : 25 { Ouisititi 1 : 28 { Gibbon 1 : 48 Rodents { Field Mouse 1 : 31 { Mouse 1 : 43 Carnivora { Mole 1 : 36 { Dogs 1 : 47 1 : 305 Birds { Blue Tit 1 : 12 { Canary 1 : 14 { Cole Tit 1 : 18 { Sparrow 1 : 25 { Chaffinch 1 : 27 The man in question is the European White. Now from this table we see that from infancy to old age the relation of the brain to the rest of the body keeps diminishing. Are we to conclude then from this that the youth is _degraded_ relatively to the infant, and that the adult or the old man has assumed a _simian character_? We see, moreover, that there ought to be some understanding as to the word _simian_ itself. If the gibbon, which belongs to the type of our supposed ancestors, has a brain relatively smaller than ours, it is otherwise with the three members of the genus cebus given in the table. The latter are superior to the anthropoid; the two first show exactly the same relation as the infant and youth; the third surpasses the adult man. But all three are surpassed by the two tits and the canary. Consequently, if we are right in regarding the human race, or the human individual whose brain is below the mean by several grammes, as tending towards the anthropoid ape, we ought to consider the race, or the individual whose brain is above the mean as approximating to the cebus, or even the passerines or conirostres. If the first comparison is admissible, the second is equally so. We can then say with the learned anatomist whose authority I have so often appealed to: “The microcephali, however reduced their brain may be, are not brutes; they are merely undeveloped men.” Or again, we may say with M. Best, whose testimony cannot be suspected in such a matter, that in their development apes do not resemble man, and, conversely, that the human type when degraded does not resemble the ape. IX. From the pithecoid man of Darwin and Haeckel, from the speechless man who used his teeth as weapons, to the man of our age, the distance is still very great. How has it been filled up? How has this intelligence been developed which is able in many cases to hold nature herself in subjection? It is Wallace who has especially answered this question in the name of the theory of which he is one of the founders. We shall see at the same time that he admits the imperfection of this theory, when he discusses the peculiar attributes of the human species.