CONTENTS. III. 



Papers Read and Published — continued. 



PAGE. 



"A Preliminary Account of Some Investigations on Leaf- 

 Aeration in certain Natal Plants," by G. W. Gale, 



B.Sc 153 



"Agricultural Experiment: Its Design and Interpreta- 

 tion," by E. Parish, B.Sc 155 



"The Life-Histories of some Trematodes occurring in South 



Africa," by Annie Porter, D.Sc 156 



"Some Parasitic Protozoa found in South Africa. IV," by 



H. B. Fantham, M.A., D.Sc 164 



"A Note on Ortalia pallens Muls.," by R. H. T. P. Harris 170 



"An Educational Experiment," by H. S. Keigwin, M.A. ... 172 



"Bantu Industries," by D. A. Hunter 183 



••The Preservation of our National Monuments," by 



C. G. Botha 195 



"Irving Fisher's Proposals for Stabilising the Value of 



Money," by Mabel Palmer, M.A 197 



Page. 

 "Asphalt in relation to Road Construction," by D. Basil 



W. Alexander 201 



"Purification of Sewage by the Activated Sludge Process," 



by R. J. Morris 215 



"On the Mechanical Analysis of Soil containing Heavy 



Minerals," by B. de C. Marchand, B.A., D.Sc 223 



"Condensed Milk in South Africa from the Chemist's point 



of view," by A. A. Kloot, B.Sc, and L. Hyman ... 227 



"The genus Passerina and its Distribution in South 



Africa," by D. Thoday, M.A 230 



"On some Fungi from the Air of Sugar Mills and their 



Economic Importance to the Sugar Industry," by 



P. A. van der Bijl, M.A., D.Sc 232 



"The Plant Succession in a Type of Midland Tree Veld in 



Natal," by R. D. Aitken, M.Sc 233 



"Protonemal Developments of Mosses," by H. Wager, 



A.R.C.S 244 



"A Contribution to our Knowledge of the Polyporeae of 



South Africa," by P. A. van der Bijl, M.A., D.Sc. ... 246 



"Bryophyta of Southern Rhodesia," by T. R. Sim, D.Sc, 



and H. N. Dixon, M.A 294 



"The Potency of Pepper Tree Pollen as a Cause of Hay 



Fever," by Geo. Potts, B.Sc, Ph.D 336 



"Natal Species of the genus Cassia," by Helena Forbes... 342 

 "Notes on some interesting or little-known South African 



Fungi," by P. A. van der Bijl, M.A., D.Sc 345 



"The Flora of Isipingo," by Helena Forbes 348 



"A preliminary account of an Interspecific Hybrid and 



Backcrosses of Digitalis," by E. Warren, D.Sc 359 



"Some Protozoa found in certain South African Soils: I," 

 by H. B. Fantham, M.A., D.Sc, and Esther Tavlor, 

 M.Sc ;. ..; 373 



32479 



