TIME OF OCCURRENCE.

On the continent of Europe, where it is less frequent, and in England hay-fever prevails in June and July. The initial attacks occur during May and June and seldom last longer than September. In India the malady chiefly occurs in February. In Australia, in and around Adelaide, where the disease prevails, it occurs chiefly in September during the time of the blossoming of the Cape weed. In his work on hay-fever, Beard essays to show how the autumnal form is peculiar to the United States. One cause seems to be the flowering of the Roman wormweed and the pollen of corn about the middle of August, and another in the prevalence of the "dog-days." A third reason lies in the fact that there is less atmospheric ozone and electricity at this period than at any other time of the year, and, again, the hottest days are frequently in the latter part of June. Beard also attached importance to a variety of hay-fever in which the attacks came on in September. This distinction is probably due to the fact that while one person is liable to the action of

one pollen, another may be affected by a totally different pollen, and the annual attacks come on when the atmosphere is permeated by a special pollen to which the victim is individually susceptible. Many persons are susceptible to the action of more than one pollen. Patients often suffer from rose colds in early summer, and, again, in August, from the autumnal form of hay-fever. Of the 198 cases collected by Beard the onset of the disease occurred

Of Bosworth's eighty cases the greatest number, fifty-one, occurred between August 10th and August 27th. The usual date assigned for the commencement of paroxysms of hay-fever is the 29th of August. This form of the disease, com

mencing in the latter part of August, is designated as autumnal catarrh.

Many patients have asserted that they are attacked annually on exactly the same date, and even the same time of day, each year. There can be little doubt that the psychic influence or peculiar mental anticipation may have a great deal to do with this circumstance. An attack may be brought on by the influence of the imagination. Phoebus gives the history of a case in which attacks of sneezing were brought on "while looking at a beautiful picture of a hay field." The well-known instance of J. N. Mackenzie, in which an attack of hay-fever was brought on in a susceptible individual subject to rose cold by means of an artificial rose may be explained on this ground. Bosworth considers that the time of occurrence is influenced by psychic causes, and is analogous to the recurrence of chills in intermittent fever, and considers that deception as to the actual time of occurrence might be proved in hay-fever as in intermittent fever, in which changing the hands of the clock may lead to a change in the regular recurrence of the chills. Prince gives the history of a case in which a hay-fever subject under the influ

ence of autosuggestion, by means of writing frequently on paper and thinking, day and night, in leisure moments, and of slight hypnotism, prevented the premonitory symptoms of hay-fever, and she was free from the annual attacks for several years, when they recurred and continued yearly thereafter. Prince asks, may it not be that the reason why certain places, such as Dublin, for instance, are reputed to have a specific influence against attacks, is the counter-suggestion thereby given that the patient will be free from attacks at such places?

DURATION.

Pirrie states that it is next to impossible to definitely decide the duration of hay-fever attacks, as seasons, age, temperament, locality, treatment, and other circumstances tend to cause variations in different years and in different individuals. Treatment will do much to curtail the duration of the more prominent and distressing symptoms, but if left to themselves it is seldom they depart under three or four weeks. A writer in the "Twentieth Century Practice of Medicine" estimates the duration as from four to six weeks, according to the patient's surroundings and the atmospheric conditions. Asthmatic attacks may last from a few hours to three days and disappear suddenly. Morell Mackenzie states that attacks last from a few hours to several days, or even longer, finally ceasing almost as suddenly as they came, and leaving no trace either in local lesions or in systemic disturbance. Bosworth gives eighty cases, showing the durations of the annual attacks as follows: