40 THE .TOITKNAL OF BOTANY 



POLLmOSlS ("HAY-FEYEK"). 



By E. Philip Smith 



(Botanic Department, Oxford). 



For catarrh caused by plant-products, and especially by the micro- 

 spores or ])oUen-grains of the Gramineae, the expression "pollinosis " 

 has been used ; tiiis is preferable to the older " hay-fever," as being 

 less ambiguous, more accurately descriptive, and not so liable to 

 misuse. Under the popular term " hay-fever " are classed together 

 almost as man^'^ abnormal conditions of the nasal membranes as under 

 the heading of "common cold," regardless of their etiolog3\ Any 

 nasal catarrh, whether it merely takes the form of abnormal secretion 

 of mucus, or is accompanied by violent sneezing, running of the eyes, 

 and even b\^ severer systemic symptoms, if it is not more or less directly 

 referable to bacterial infection consequent upon exposure to cold, etc., 

 is, especially if it occurs in the summer or autumn, unhesitatingly 

 described as '* hay-fever." 



For the purpose of these notes, it is proposed to set aside all types 

 of corrhiza which prove upon inquiry to be due to causes other than 

 plant-products, such as those caused by exposure to the dense dust 

 which gathers in libraries, by exposure to bright light — this will be 

 touched upon later — or by the animal detritus from the coats of 

 liorses, cats, and even dogs. Even when circumscribed by the removal 

 of these other types, the detinition of hay-fever is sufficiently wide to 

 makij it of interest to many, and of painful interest to its victims. 



The clinical picture is well known. The onset of the attack, 

 which may follow directly on exposure to pollen, or after the lapse of 

 a certain time varying from live minutes to half an hour, is marked 

 by violent sneezing, profuse secretion of watery mucus, running at 

 the eyes, and a feeling of helplessness and malaise. In some subjects 

 nasal and bronchial stenosis may be felt at the height of the paroxysm. 

 This primary attack may last only a few minutes, or it may be pro- 

 longed until the patient is exhausted, and fresh parox^^sms occur on 

 each new exposure to the source of irritation. After some days of 

 this the nasal mucosa, the conjunctival surfaces, and even the bronchi 

 in severe cases, become acutely sensitive, and very little is required to 

 produce an attack, even without further exposure to pollen, the stirring 

 up of dust from books, a draught of cold air, even exposure to bright 

 light (in cases where the eyes are much involved) being sufficient. If 

 it were always possible accurately to disentangle the evidence, it would 

 be possible to make a clear distinction between primary attacks due 

 to direct infection, and these secondary effects of other irritants on an 

 already damaged mucous membrane. The danger- season, however, is 

 so prolonged (with some it begins with the flowering of Willows), 

 lasting from spring till the first frost in autumn, that few people 

 could submit to the rigid exclusion from vegetation wdiich would be 

 necessary for an accurate experiment to be made on the relative 

 importance of the primary and secondary causes. 



Enough has been said to show that true hay-fever is sufficiently 

 mdespread to make it of interest to the botanist to stud}^ the plant- 



