Article VII.— DOLICHOCEPHALY AND BRACHYCEPH- 

 ALY IN THE LOWER MAMMALS.' 



By Henry Fairfield Osborn. 



Skulls are classified according to their cephalic indices into three 

 groups: dolichocephalic, mesaticephalic, and brachycephalic. — Nature, 

 XXXIII, 4. 



Dolichocephaly and brachycephaly are familiar terms in 

 anthropology. The cephalic index, or ratio of breadth to 

 length, marks a profound distinction between different races 

 of man; it is one of the most stable of all racial characters, 

 although no satisfactory theory or explanation of what it 

 signifies has thus far found general acceptance among anthro- 

 pologists.^ 



These facts render it all the more surprising that skull pro- 

 portion, distinguished from cranial or brain-case proportion 

 in man, has not been con- 

 sidered more generally by 

 students of the lower mam- 

 mals as of great value in 

 the separation of races, as 

 well as of profound mor- 

 phological significance. It 

 is true that certain mam- 

 mals have been described 

 as short- or broad-skulled, 

 others as long- and narrow- 

 skulled. As early as 1873 Kowalevsky demonstrated the 

 elongation of the face in Ungulates for the accommodation of 

 long-crowned teeth, but this does not explain the long free 

 space or diastema in front of these teeth; the studies of Nathu- 

 suis (1864) on the proportions of the skull in races of pigs, 



Fig. I. Human Crania of dolichocephalic and 

 brachycephalic type. After Huxley. 



' Presented in Abstract before the New York Academy of Sciences, Nov. 8, 1901, and 

 before the National Academy of Sciences, Nov. 13, 1901. ^ 



- I make this statement on the authority of Dr. A. Hrdlikca of the American Mu- 

 seum of Natural History. 



L77] 



