NATIONAL CHARACTERISTICS OF SKULLS. 215 



but as there is not much variation in the thickness of the 

 scalp in different heads or on opposite sides of the same 

 head, I do not admit this to be a source of error *. 



The lesson that these tracings teach is a very plain one, 

 amounting in a word to this, that the skull-forms of 

 (probably) every living nation range from extreme types 

 of dolichocephalism to extreme types of brachycephalism, 

 and constantly present examples of every intermediate 

 form. 



Turning to the tracings, Nos. 1-16 are English skulls. 

 Of these, nos. 1, 2, 3, 5, 6, 7, 8, 9, 10, and 16 are dolicho*- 

 cephalic, 13, 14, and 15 are brachycephalic, and 4, 11, 

 and 12 are of a median type, and may be termed meso- 

 cephalic. No. 16 is an extreme type of dolichocepha- 

 lism, the skull measuring 8 inches from before back- 

 wards, and 6 inches from side to side. This gives a 

 cephalic index of 75 f. 



No. 15 is a type of brachycephalism, the skull measuring 

 7f inches from before backwards and 64- inches from side 

 to side, which gives a cephalic index of 88* 1. 



Nos. 17-28 are German skulls, which are described by 

 Retzius as dolichocephalic. There is not a single dolicho- 

 cephalic skull amongst these examples, which were taken 

 quite haphazard. The nearest approach to dolichocepha- 

 lism is afforded by No. 17, in which the skull measures 

 71 by 6-| inches, which gives a cephalic index of 82*2. 

 The extreme type of brachycephalism (No. 28) measures 

 7t by 6-§- inches. 



* The lithographic drawings are exactly one third the size of the original 

 tracings ; so that, to obtain the real outline of any skull from them, it is neces • 

 sary first of all to multiply the antero-posterior and transverse diameters 

 by three, and then to add 2 inches to each product. 



t The cephalic index is the relation which the transverse diameter of the 

 skull bears to the antero-posterior diameter, the latter being taken at 100. 

 When the former reaches 80, the skull is brachycephalic; when below that 

 number, it is dolichocephalic. 



