Notes on some Bushman Crania and Bones. 249 



portions as the Negroid Egyptian type. The Hottentots in this 

 respect are not intermediate between Bushmen and Kaffirs, but 

 more closely resemble the Bantu-speaking Negroes of Nyasaland — 

 a feature previously noted in their general appearance. The Pigmy 

 is quite distinct from all these groups, but in relative dimensions 

 resembles the Western group of Bantu, occupying the seaward 

 margin of the great forest zone. 



From the general table of average dimensions it may be seen that 

 the Western Bantu differ from the Eastern just in the features in 

 which the former resemble the Pigmies. It is tempting to consider 

 whether they may not be regarded as a Pigmy-Bantu cross in the 

 same manner that the Hottentots have been as a Bushman-Bantu 

 cross. 



The accompanying table records the average dimensions of the 

 skulls of each group that has been used for contrast. The 

 standard deviations, the coefficient of variation, and the value of 



=- are given to facilitate comparison. The probable error of 



each average is given to show the accuracy of the result, which 



depends on the number of observations available. The probable 



„„_,_ Standard deviation 



error is + 0-5745 x mu z — rri, 1 e — u r — 



~ ihe square root of the number of observation 



i.e., + 0'6745 ,^ That is, the accuracy increases with the number 



of observations in the ratio of the square root of that number. The 

 probable error decreases as the standard deviation decreases. 



SUMMARY. 



The Strandloopers appear in all respects to be a purer group than 

 the Bushmen, and to be distinct from the Hottentots, though the 

 influence of chance selection cannot be quite excluded, owing perhaps 

 to the small amount of material available. 



The up-country Bushmen appear intermediate between the 

 Strandloopers and Hottentots. 



The Hottentots present dimensions exactly intermediate between 

 the preceding and the Bantu. They show in many features a 

 smaller coefficient of variation, which tends to prove that the cross, 

 if such is the true explanation, was of some standing and very com- 

 plete. In many characters they approach the Negroes of British 

 Central Africa more closely than the Kaffir tribes of the East 

 Coast. 



