Dopter reports recurrent epidemics of influenza in a French Army Division in 1918. The division, of which he was surgeon, was one of the first to contract la grippe at the time of its first appearance in the zone of the armies at the end of April, 1918. At this time nearly the entire body of infantry troops was attacked. The disease was mild, and without complications. The regiment of artillery escaped nearly entirely. This epidemic subsided very rapidly, and by the end of May it had entirely disappeared. Early in August a group of heavy artillery was attached to the division, bringing influenza with it. Then a few cases appeared in the regiment of light artillery which had hitherto escaped. By the end of August all three groups of this regiment had been attacked. In this second epidemic the men who had come through the first unattacked were very severely ill in the second. With rare exceptions those sick in the first did not contract it again. Dopter notes that in the battery the most severely affected in August, of which the effectives were reduced almost to none, only those men were considered well enough for duty who had had influenza in the first period. They escaped the second in spite of the close contact with their comrades. The infantry regiments, which were in close association with the artillery, remained unaffected. Finally, toward the middle of September new troops were attached to the division, in view of an imminent attack by the enemy. These troops, coming from neighboring and distant formations were suffering at the time from grip, and continued to have the disease in the new sector. Again, those attacked in May passed without damage through this new epidemic. Among them there were only rare isolated mild cases. The recurrences made only 1.6 per cent. of the total incidence. Opie and his associates found that at Camp Funston after the first wave of influenza in March and April, 1918, the succeeding waves usually affected only new recruits, who had not been in camp during previous waves. In Calcutta influenza appeared as an epidemic in July, 1918, and in November, 1918. During the first quarter of 1919, at Calcutta as elsewhere, many cases were still recurring. Malone investigated the incidence of the disease in three institutions of Calcutta: He found that in the Gourepore Jute Mills where the population was practically stationary, those individuals who were attacked in July, 1918, passed through two later epidemics, in December, 1918, and February, 1919, without contracting the disease a second time, in spite of intimate contact with infected persons. The same was true according to Malone in the Alipore Central Jail and the Presidency Jail in Calcutta. He believes that his evidence strongly suggests an immunity lasting for at least nine months.