THE 



SOUTH AFRICAN JOURNAL 

 OF SCIENCE 



COMPRISING THE REPORT OF THE 



SOUTH AFRICAN ASSOCIATION FOR THE 

 ADVANCEMENT OF SCIENCE 



(1922, LOURENCO MARQUES). 



Vol. XIX. DECEMBER, 1922. Vol. XIX 



EDITORIAL NOTE 



The attention of Members of the Association and readers 

 is directed to the fact that, in view of the prevailing circum- 

 stances, the Council of the Association has decided that the 

 Journal sliall be issued as a single volume, containing the papers 

 recommended for publication after having been read at the Annual 

 Meeting. The present issue is thus complete in itself, and foiins 

 Volume XIX of the Keports of the Association. 



Information regarding the activities of the Association, its 

 previous Reports and the cost of back numbers can be obtained 

 from the Assistant (leneral Secretary', P.O. Box 6894, Johannes- 

 burg, Transvaal. 



H. B. F. 



