30 LECTTJRE II. 



regards the median plane, and tliat in this respect the ex- 

 tremest dolichocephaly and brachycephaly show no difference 

 whatever. The variations to which the occiput is subject are 

 in some cases so abnormal and so great, even within individual 

 limits, that they cannot be regarded as influencing the general 

 law. Opposed to this constancy of the median plane, the dif- 

 ferences in the frontal planes are the more striking. Here the 

 cranial forms decidedly separate into narrow and broad. Each 

 is distributed into particular regions ; the former belonging to 

 the southern, the latter to the northern, hemisphere. Africa 

 and Polynesia, with New Holland, ofier the narrowest, Eu- 

 rope, with Northern Asia, the broadest, forms of skulls. 

 Southern Asia is intermediate between both divisions, not 

 merely because its inhabitants (Chinese and Javanese, for 

 instance) possess generally a medium breadth of skull ; but 

 also especially because some districts repeat the type of the 

 most decided narrow skulls {e. g. Hindu), others, that of the 

 broad skulls (some islands in the vicinity of Java) . It is re- 

 markable that the Greenlanders, though a high northern people, 

 possess the most decidedly narrow skulls which exist. How 

 it is in the rest of America I am unable to say, as I had not 

 sufficient materials at my disposal. Both types seem repre- 

 sented. Some, at least, of the Brazilian peoples are narrow- 

 headed ; whilst the Botocudos and the Indians of the North are 

 more or less decidedly broad-headed. The measurements, as 

 already stated, all refer to the reduced skull, and are, therefore, 

 independent of absolute size. I have not succeeded in finding 

 a definite law of development for the latter. 



"All difierences, therefore, of the human cranial form de- 

 pend essentially on the difference in the development of breadth. 

 Platycephaly stands opposed to leptocephaly, though connected 

 with it by gradual transitions. The uniform development of 

 the median plane in the whole human species, appears to me a 

 fact of the greatest interest. Not less important seems to me 

 the observation that ethnic differences do not much obtain in 

 childhood ; for between the infantile skulls of Negroes and Eu- 

 ropeans I find the greatest accordance. Median planes and 

 frontal planes cover each other completely ; an important fact 



