78 BONES OF THE HEAD. 



first years of childhood the superior parts of the cranium grow more rapidly than 

 the base. Thus, in the frontal region, the upper i^art of the frontal bone grows 

 more rapidly than its orbital processes, giving the prominent appearance of the 

 frontal eminences peculiar to children. The face at birth scarcely reaches 

 an eighth of the bulk of the rest of the head, whUe in the adult it is at 

 least a half (Froriep, " Characteristik des Kopfes nach dem Entwicklungsgesetz 

 desselben, 18-15 "). At the same time that the face increases in bulk, the lower 

 part of the forehead is brought forward by elongation of the anterior cranial 

 fossa, and on the approach of adult age, especially in the male, it becomes 

 ytUl more prominent by the expansion of the frontal sinuses. The face 

 becomes elongated in the progress of growth, partly by increased height 

 of the nasal fossfe and adjacent air-sinuses, partly by the growth of the teeth 

 and the enlargement of the alveolar arches of the jaws. In old age the jiropor- 

 tion of the face to the cranium is diminished by the loss of the teeth and absorp- 

 tion of the alveolar portions of the jaws. In consequence of this the upper jaw 

 reti'eats, while in the lower jaw the same cause gives, especially when the mouth 

 is closed, a greater seeming prominence to the chin. 



II. Sexual Differences. — The female skull is, in general, smaller, lighter, 

 and smoother than that of the male ; it is less marked by muscular pi-ominences, 

 and has also the frontal sinus less developed. The face is smaller in proj^ortion 

 to the cranium, the jaws narrower, and the frontal and occipital regions less 

 capacious in proportion to the parietal. (Huschke.) The female skull resembles 

 the young skull more than that of the adult male ; but it must also be admitted 

 that it is often impossible to detennine the sex hy the appearance or form of 

 a skull. 



III. National Differences. — Tliat characteristic forms of skull are presented 

 by the various races of men has probably been long kno\^ai, but was fii'st dis- 

 tinctly pointed out by Camper. Subsequently the investigations of Blumenbach 

 established the connection between the study of these forms and ethnology, which 

 since his time has been maintained and greatly extended. The extent, natvu'e and 

 constancy, however, of the ethnical differences of skulls are subjects open to dis- 

 cussion. But. although many skulls are to be met with which fail to exhibit the 

 common characteristics of the race to wliich they belong, or which j^resent jDecu- 

 liarities similar to those of nations considerably removed from them, j^et, it must be 

 admitted, that there are certain forms of skull highly distinctive of the principal 

 varieties of mankind, and often even distinguishable in nations mhal:)iting countries 

 not far removed from one another. Great differences occiu- with respect to size in 

 the skulls of different nations. Among the smallest skulls may be mentioned those 

 of the Hindoo, the ancient Peruvian, and the Bosjesman ; among the most mas- 

 sive those of the Scandinavian, the Caffre, and the Maori. Various characters 

 are found belonging to the skulls of rude tribes, which serve to distinguish them 

 from those of civilised nations.X Among those characters may be mentioned, — a 

 depressed appearance between the middle line of the calvarium and the temporal 

 ridges, both of which stand out 23rominently, making the roof of the skull seem 

 lilve a house top ; a greater width of the zygomatic arches, and of the anterior 

 nares ; greater length and strength of the jaws, together with projection forwards 

 of the incisors, so that the teeth of the upper meet those of the lower jaw at an 

 angle, instead of both sets being nearly perpendicular, as in cultivated nations. 

 Elongation of the face doMniwards may be regarded as a specially human charac- 

 teristic connected with the use of voice and si^eech. but projection of the jaws 

 forwards is only advantageous for the seiziu'e of food, and gives an appearance 

 of approach to the still fm-ther projected fonn of the jaws in the lower animals, 

 particularly when accompanied, as it often is, by deficient development and 

 receding form of the chm. 



The average horizontal circumference of the British male cranium, taken one 

 inch above the orbits, is about 21 inches, varying however frequently between 

 20 and 22 ; the antero-posterior diameter is about 7^ inches, and the greatest 

 transverse (parietal) diameter is about .5| inches. The average height of the 

 skull from the plane of the foramen magnum to the vertex is about ii^ inches. 

 The average capacity of the well-fonned British male cranium may be stated 

 at from 90 to tto cubic inches, vai-ying in extremes from about 70 to 120. That 



