"3rd. In some of the races of man, the arch of the skull, instead of presenting a uniform curve in the transverse direction, bends a little towards the top of the two sides, and rises towards the median line (New Caledonians, Australians, &c.). It is asked if this is not a preliminary step towards the bony crests which rise in this region in some of the anthropomorphous apes?
"Again we reply in the negative; for, in the latter, the bony crests arise from the walls of the skull, and do not form any part of the arch.
"4th. Is it not very remarkable that we find the orang to be brachycephalous, just like the Malay, whose country it inhabits, and that the gorilla and chimpanzee are dolichocephalous like the negro? Is not this fact a reason for our regarding the former animal as the ancestor of the Malays, and the latter of the African nations?
"Even if the facts brought forward were correct, the inference which is drawn from them would be far from satisfactory. But the coincidence which is appealed to does not exist. In point of fact, the orang, which is essentially a native of Borneo, lives among the Dyaks and not among the Malays; now the Dyaks are rather dolichocephalous than brachycephalous. With respect to gorillas being dolichocephalous, they cannot at least be so generally; as out of three female specimens of this ape which were examined, two were brachycephalous (Pruner-Bey).
"5th. The brains of microcephalous individuals present a mixture of human and simial characteristics, and point to some intermediate conformation, which was normal at some anterior epoch, but at the present time is only realised by an arrest of development and a fact of atavism.
"Gratiolet's investigations of the brain of the ape, normal man and small-brained individuals, have shown that the similarities pointed out are purely fallacious. People have thought that they could detect them, simply because they have not examined closely enough. In the last named, the human brain is simplified; but this causes no alteration in the initial plan, and this plan is not that which is ascertained to exist in the ape. Thus Gratiolet has expressed an opinion which no one has attempted to controvert: 'The human brain differs the more from that of the ape the less the former is developed, and an arrest of development could only exaggerate this natural difference.... The brains of microcephalous individuals, although often less voluminous and less convoluted than those of the anthropomorphous apes, do not on this account become like the latter.... The idiot, however low he may be reduced, is not a beast; he is nothing but a deteriorated man.'
"The laws of the development of the brain in the two types, laws which I mentioned before, explain and justify this language; and the laws of which it is the summary are a formal refutation of the comparison which some have attempted to make between the contracted human brain, and the animal brain, however developed.
"6th. The excavations which have been made in intact ancient beds have brought to light skulls of ancient races of man, and these skulls present characteristics which approximate them to the skull of the ape. Does not this pithecoïd stamp, which is very striking on the Neanderthal skull in particular, argue a transition from one type to another, and consequently filiation?
"This argument is perhaps the only one which has been brought forward with any degree of precision, and it is often recurred to. Is it, on this account, more demonstrative? Let the reader judge for himself.