TWENTY-FIFTH ANNUAL MEETING. 127 



the latter are quite prognathous, and thereby approach the quadrumanous type; 

 but civilized jaws stop short of the full development of the anthropoid form. That 

 is, in the monkeys the jaws are more prominent than in man, and as this results 

 from a fuller course of growth from the infant, it is evident that in these respects 

 the apes are more fully developed than man. The reduced jaws are characteristic 

 of retardation. In the negro and Mongolian we notice that there is a predominance 

 of the quadrumanous features (prognathous jaws) which are retarded in the Indo- 

 European; and that the embryonic characters which predominate in the last (orthog- 

 nathous jaws) are more accelerated in the others. In the negro the edges of the 

 jaws are prominent — a quadrumanous characteristic; in the higher races the alve- 

 olar borders are reduced. . . . The edges of the jaws are more prominent in the 

 quadrumana. . . . In the monkey the jaws grow more from infancy to maturity 

 than in man." Prognathism is a quadrumanous character, and its opposite, orthog- 

 nathism, a human character. The teeth project in most low races, and are more 

 vertical in most civilized races, and this adds to the character of the jaws, whether 

 prognathous or orthognathous. These characters are very constant as racial fea- 

 tures, there being but infrequent individual deviation from the racial type, and per- 

 haps only in the higher races, in the cases of congenital idiots, who sometimes have 

 prognathous jaws, owing largely to the nondevelopment of the brain case. Darwin 

 says ("Descent of Man"), quoting Vogt: "Microcephalous idiots have a smaller 

 brain, less complex convolutions, the frontal sinus is largely developed, the jaws are 

 prognathous to an effrayant degree; so that these idiots somewhat resemble the lower 

 types of mankind." Indeed, prognathism and a small brain case, or orthognathism 

 and a large brain and prominent forehead, bear a constant relation to each other. 

 In the higher races, with greater mental power, the brain is larger — at least the fore 

 brain — and causes the brain case to grow forward and overshadow the jaws, which 

 are correspondingly and synchronously reduced. And, vice versa, prognathous jaws 

 project forward of the brain case, which is reduced and smaller. Thus it is that 

 small, orthognathous, vertical jaws and large brain go together, and large, progna 

 thous jaws and small brain together, as more or less constant racial characteristics. 



"In the infant the alveolar borders are not prominent. . . . The faces of 

 some people are partly embryonic," in having a short face and light lower jaw. 

 Such faces are still more embryonic when the forehead and eyes are prominent. 

 "Retardation of this kind is most frequently seen in children, and more frequently 

 in women than in men." An undeveloped, retracted lower jaw is an embryonic form 

 sometimes seen. 



In the quadrumana "the mouth is small and the lips thin. . . . The strong, 

 convex upper lip, as frequently seen among the lower races of Irish, is a modified 

 quadrumanous character " (Cope, op.ciL), and is quite constant in their descendants. 

 The lips are distinctly cleaner and finer cut in the higher European races than in 

 the lower races of man, and the oral opening is smaller. A large, wide opening to 

 the mouth, with coarse lips, is a low type, and, when associated with depressed cor- 

 ners, is positively quadrumanous. These forms are often seen in low races, and 

 sometimes reappear in individuals of the higher races. The lips are coarse and 

 shapeless in all low races, and the finely-carved lip is a distinct mark of superior 

 organization. In the quadrumana the lips are thin and infolded, showing but little 

 of the mucous membrane. Thus, a mouth that is wide and much depressed at the 

 corners, with thin lips and a long, stiff upper lip, is positively quadrumanous. The 

 inheritance is direct. The thick lip, that shows much of the mucous membrane 

 folded outward, is embryonic. It is infantile, and remains as a permanent feature 

 in most lower races, and in some individuals of the higher races. It is the remains 

 of the nursing period, like the developed buccinator muscle. 



