186 



PEPPER TREE AS A CAUSE OF HAY FEVER. 



the weather was dry and breezy ; rain tell during the night and 

 the following day was windy. The pepper tree was in flower at 

 the time, but there was little or no hay fever. No pollen of any 

 kind was found on the slides ; but there w^as grit present, showing 

 that, during at least part of the period of exposure, dust had 

 been blowing about. One of the slides was exposed within 50 

 yards of a male pepper tree. Another parcel of slides sent to 

 Johannesburg met with an accident. Weather records for the 

 month are given in Table XVIII. 



Table XVIII 

 Meteorological Observations : Johaxxesburg, 1920. 



(c) Drying of Pepper Tree Pollen in Oilier Towns. 



The result of exposing pollen plates in Kimberloy, Grahams- 

 town, ]Maritzburg and Johannesburg was that whilst pepper tree 

 pollen was plentiful on the plates exposed in Kimberley, none 

 was found on plates exposed in any of the other centres. The 



