THE 



SOUTH AFRICAN JOURNAL 

 OF SCIENCE, 



COMPRISING THE REPORT OF THEAN- oP'**- <. 



SOUTH AFRICAN ASSOCIATIOlVLjbR. 



FOR THE V'^iN^Ae 



ADVANCEMENT OF SCIENCE. 



(1919, KINGWILLIAMSTOWN.) 



Vol. XVI. OCT.-DEC. 1919. No. 3. 



EDITORIAL. 



The Journal of the Associaticn, in this number, passes under 

 the control of another Editor, owing to the removal of the head- 

 quarters of the Association to Johannesburg. In taking leave, 

 regretfully, of Dr. C. F. Juritz as Editor, the Council wishes to 

 place on record its hearty appreciation and thanks for his long 

 and faithful service, and trusts that he may still continue to act 

 as one of the General Secretaries, and aid in the affairs of the 

 Association. 



Some apology is due to members of the Association for the 

 delay in issuing the Journal. However, it may be pointed out, 

 without wishing to make excuse, that the present times are 

 difficult and abnormal, especially in printing. Efforts are 

 now being made to publish the Journal more expeditiously, and 

 to issue it to date, and contributors are asked to help in this 

 matter by revising and returning their proofs quickly, and by 

 carefully observing the essential instructions, few in number, 

 regarding illustrations given on page 2 of the cover. 



Communications for the Editor should, in future, be 

 addressed to P.O. Box 1176. Johannesburg. All other com- 

 munications relating to the activities of the Association should 

 be addressed to the Assistan*^ General Secretary, P.O. Box 6894. 

 Johannesburg. 



TT p. F. 



A 



