THE CRANIOLOCJY OF MAN AND ANTHROPOID APES. 435 



reo-ulatc the apiiiiratiis' iicccssarv for the pi-odiu-tioii of articulate 

 speech, that the other pai'ts of their anterior lobes lia\(^ reiiiaiiied in 

 a comparatively undevelojx'd condition; whercnis the left inferior 

 frontal lolte of nian's l)rain haA'in"' l)econie hiohly s])ecialized, and 

 with it his })o\ver of language, the other convolutions of liis anterior 

 lobes, which govern his intellectual faculties, have been stimulated to 

 increased action, and in this way the characteristic expansion of the 

 fore brain has been evolved among all the more highly civilized races 

 of the human family. 



Hut our contention is that the factors which govern the growth of 

 the skull diti'er from those which deveh)p the l)rain, and that the 

 im})erfect evolution of the frontal lobes among anthropoid apes is to 

 a large extent due to the premature ossification of that part of the 

 skull which incloses the fore brain and to the remarkable convexity 

 of the orbital plates of thi^ frontal ])one. Howevei" this may be, the 

 possession of fully developed anterior lobes of the brain, especially of 

 its left inferior gyrus, is the distinctive character of the central ner- 

 vous system of all those families of mankind who possess Avell-developed 

 intellectual capacities. On the other hand, if we compan^ the skull of 

 an Englishman (with a cranial capacity of 1,575) with that of one of 

 the natives of northern Australia (with a cranial ca])acity of 1,160), 

 we see what a wide diti'erence there is between tlu^ development of 

 their frontal regions and also as to the nature of tlie sutures of their 

 skulls." (This point is clearly illustrated in the photographs taken from 

 the skulls of "" existing races of men,"' as shown in the lower seciion 



"Professor Huxley held that the organization of the human brain had more to do 

 with man's intellectual superiority tlian either its weight or size, anil there can be 

 no question that men having suiall heads are by no uieans necessarily wanting in 

 mental capacity; but a well-developed frontal region is a characteristic feature of all 

 the more highly civilized connnunities of the world, and among such i^eople low 

 intellectual endowments or even idiocy is found to be comparatively frequent in those 

 with abnormally small frontal lobes (see note, p. 103, Man's I'lace in Nature). We 

 agree fully with Professor Iluxley that among all the known races of human beings 

 the brain and its including case, the skull, grow together, and the former does not 

 exercise an absolutely predominating influence over the development of the latter. 

 But it is certain that if the anterior part of the skull becomes a " shut i')\" early in 

 life, it must control the subsequent size and development of the brain which it con- 

 tains. Professor Weh^ker, who studied this subject in a thorough Teutonic spirit, 

 arrived at the conclusion that in European races the frontal suture remains opens up 

 to the adult period of life in one out of nine persons. Among Afri(;an races it is not 

 found open at the adult period of life in more than one in one hundred and fifty 

 persons; and among the aborigines of Australia no adult skull has yet been observed 

 with an open frontal suture. The well-known French anatomist Gratiolet states as 

 a result of his researches that "not only tlu^ growth of the brain ceases sooner in 

 those races in which the sutures (dose early, hut also that there is a difference between 

 the higher and lower races as to the order in which the sutures :ire closed normally 

 In the latter the anterior sutures consolidate before the posterior, and in the higher 

 races it is the reverse; the posterior sutures close earlier than the anterior." M. 

 Gratiolet Imses an argument for the greater perfectibility of the higher races upon 



