44 LECTURE II. 



the adult. But it is differeut witli the angle of the sella, which 

 is more obtuse in the child than in the adult, so that in this re- 

 spect the correct proportion is estabhshed. But according to 

 Welcker's researches, there is a great difference as regards the 

 formation of this angle between man and even the ape nearest 

 allied to him. It is well known — and we shall subsequently re- 

 vert to this point — that in the most anthropoid apes, the chim- 

 panzee, gorilla, and orang, the young animal in every respect ' 

 resembles man more than the adult, and that this relapse 

 to the semblance of the brute, consists essentially in the fact 

 that the cranium remains stationary as regards cerebral capa- 

 city ; whilst the jaws and the whole face are greatly developed, 

 and project in the form of a muzzle. In correspoitdence with 

 this, we find that, e. g., in the orang the angle of the sella is 

 the more obtuse the older the animal is; whilst, on the contrary, 

 in man this angle is smaller in the adult than in the child. 

 " If," says Welcker, " the skulls are arranged according to 

 Camper^s angle, the skull of the infant, contrasted with that of 

 any animal, occupies a higher place than the skull of the adidt ; 

 but if the skulls are arranged according to the increasing 

 size of the angle of the sella the series stands : man, woman, 

 child, animal." 



If a fourth point be added to the three which mark the angle 

 of the sella, namely the nasal spine, and if these points are 

 connected by lines, we obtain an irregular quadrangle, which 

 pretty nearly circumscribes the whole face, exclusive of the 

 lower jaw, and the form of which depends on the development 

 of the bones and their curvatures. The four corners of this 

 quadrangle might be termed the sella-angle, the nasal-angle, 

 the dental-angle, and the foraminal-angle ; and we may, by 

 comparing these angles in different individuals and races, 

 discover important and constant proportions in direct relation 

 to the development of the face and the base of the skull. A 

 diagonal of the facial quadrangle, drawn from the anterior 

 margin of the occipital foramen to the root of the nose, and of 

 which the length can be easily estimated in either opened 

 or unopened skulls, is so far important, that it corresponds 



