374 Transactions of the Royal Society of Soittli Africa. 
to the curves, obtains in the cervical and thoracic regions as well. The 
adaptation must therefore in the South African Bushman be entirely 
cartilaginous, for there is reason to believe that the lower races have 
as strongly developed curves when erect as the higher races. The only 
proof afforded as yet are Cunningham's section of an Australian spine, and 
his index of ensellure on living Bush natives. What, it may be asked, 
does the differences in construction, namely, (1) cartilaginous arrangement, 
(2) less obliquely placed laminae and spines, (3) narrowness of the bodies 
in an antero-posterior direction, mean ? In higher races the spine has 
sacrificed flexibility for stability. Lower races have preserved the supple- 
ness essential for their mode of life and needs, hence in the maintenance 
of the erect attitude the ligamentous and muscular mechanism must 
be brought more into play than in higher races. 
Cervical Vertebrae. 
Anterior and Posterior Vertical Diameters of the Bodies. 
European. 
No. 1. 
No. 2. 
No. 3. 
No. of 
Vertebra. 
Anterior. 
Posterior. 
Anterior. 
Posterior. 
Anterior. 
Posterior. 
3 
14 
14 
13 
12 
13 
13 
4 
13 
12 
13 
12 
10 
11-5 
5 
14 
13-5 
11 
12 
14 
12 
6 
14 
14-5 
13-5 
14 
13 
13 
7 
14 
15 
13 
13 
13-5 
14 
Total 
69 
69 : 
63-5 
63 
63-5 
63-5 
Sum total of Anterior Vertical Depths, 196*5. 
Sum total of Posterior Vertical Depths, 195*5. 
Index 99-9. 
Bushman. 
No. 1. 
No. 2. 
1 No. 3. 
No. of 
Vertebra. 
Anterior. 
Posterior. 
Anterior. 
Posterior. 
Anterior. 
Posterior. 
3 
10 
10-5 
9 
10 
4 
10 
10 
10 
10 
5 
10 
10*5 
10 
10 
6 
10 
10*5 
10 
10 
7 
11 
11-5 
10*5 
Total 
51 
53 
50 
50*5 
Sum total of Anterior Vertical Depths, 101. 
Sum total of Posterior Vertical Depths, 103*5. 
Index 102*5. 
