146 



THE PEPPEK TEEE (SCHIAWS MOLLE L.) AS A CAUSE 

 OF HAY FEVEK IX SOUTH AFKICA. 



BY 



Geo. Potts, B.Sc, Ph.D., 



Prufcssof of Botdinj, Grey Uiiiversit y College, Bloemjonicin. 



Read July 11, n)'i2. 



Contents. 



Page. 



I — Introduction ... ... 146 



II — ^Climate of Bloemfontein ... ... ... ... 147 



III — Determination of Pollens in the Air of Bloemfontein during 



the Epidemic Hay Fever Season ... ... ... ... 155 



(a) Method and E.xperiments in October and November, 



1919 155 



(b) Experiments in November and December, 1920 ... 162 



(c) Experiments in November and December, 1921 : and 



General Remarks on the Three Years' Results... 165 



IV — Is lepper Tree Pollen Capable of Causing Hay Fever? ... 166 



V — Pollens in the Nasal Discharge of Hay Fever Patients ... 167 



VI— Sterility of Pepper Tree Pollen ... ' 168 



VII — ^Shape and Size of Pepper Tree Pollen 168 



VIII. — Pollination of the Flowers of the Pepper Tree ... ... 168 



IX- — Effect of the Weather on the Drying of the Pollen of the 

 Pepper Tree ; and on the Opening and Shedding of the 



Male Flowers 169 



X — Toxicity of the Leaves and Flowers of the Pepper Tree ... 173 



XI — Pollens in the Air of Bloemfontein, jNIarch, 1920 175 



XII — Difficulties in Accepting the I epper Ti-ee as a Cause of Hay 



Fever ... ... ... ... ... ... ... ... 177 



XIII — Comparison of Bloemfontein with other Towns in wiiich the 



Pepper Tree Occurs 180 



(a) Number of Pepper Trees in Various Towns and 



their Density ... ... ... ... 181 



(b) Pollens in the Air of other Towns 182 



(c) Drying of Pepper Tree Pollen in other Towns ... 186 

 XIV — Prevention Recommended ... ... ... ... ... ... 191 



XV— Dust 192 



XVI — Other Causes of Hav Fever ; and Hav Fever Symptoms in 



Bloemfontein " ' 192 



XVII— Dr. Ashe's Results 193 



XVIII — Acknowledgments ... ... ... ... ... 193 



XIX — Summary 194 



References ... ... ... ... ■. 195 



I. Introduction. 



Hay fever is an affliction of the nose, throat and eyes caused 

 in nature by contact with pollens carried in the air. The 

 syixiptonis are irritation, reddening and swelling of the mucous 

 membranes of these organs, accompanied by a profuse watery 

 discharge. It is thought that these sj^mptoms are induced by 

 poisonous (toxic) proteids, contained in the pollen grains, irri- 

 tating the membranes concerned. Eecent investigations have 

 shown that similar syinptoms may be induced by causes otlier 

 than pollen (Freeman, 1920), but the term hay fever or pollin- 

 6sis is used where the exciting agent is pollen. 



