( 60 ) Native soldiers, as among European, the practice of trying to carry on their duties as long as possible without reporting sick is very common, and this practice, of course, increases very much the liability that pernicious symptoms will develop. (2) Quinine prophylaxis is very carefully and thoroughly carried out among prisoners, and although it does not always prevent infection it lessens the severity of the attack. If these factors were not in operation we should expect the fatality of malarial fevers to be much higher among prisoners than among Native troops because among the former class there are large numbers of old and infirm men and women in whom an attack of malaria is a much more serious matter than in the younger and more robust European or Native soldier. As regards the fatality of the disease among other classes of people in India we can add that among 3,402 cases which occurred among the wives of European soldiers, and were treated in hospital during the ten-year period ending with 1907, there were 37 deaths, a case mortality of about 1 per cent., and that among 5,128 cases occurring in the children of European soldiers during the same period there were 86 deaths, a case mortality of 1.68 per cent. There are no Indian statistics which can be relied upon for calculating the fatality of malarial fevers in patients who are untreated, but anyone who has to study malaria in Indian villages cannot fail to observe that at any rate a very large number of infants and young children pass through many attacks of malarial fever without, apparently, being greatly affected by the disease, and that such children gain an immunity to malaria which is of service to them throughout their lives. The statistics dealt with above include, of course, all forms of malarial fever, but it is important to remember that serious symptoms and death occur, as a rule, only in cases of infection with the Malignant Tertian parasites. If the statistics of the ordinary intermittent fevers which are produced usually by the Benign Tertian and Quartan parasites were considered alone we should find that among European soldiers treated in hospitals in India not more than 1 patient in every 850 dies, and among Native soldiers not more than 1 in every 520. It is fortunate therefore