1. Fusarium niveum does not grow under strictly anaerobic condition, though it grows vigorously in the presence of small quantity of oxygen within the tube in BUCHNERa'sp paratus. 2. Fus . niveum reduces nitrate well in 5 per cent glucose RICHARDS solution or in 0.2 per cent starch RICHARDS so lution (Table 1). 3. The fungus grows vigorously in the nitrite m e dia an dconsumes nitrite as well as nitrate (Table 2). 4. Various sugars such as glucose, maltose, sucrose, lactose, and glycerin were used for the carbon sources of culture media. In each medium containing 2 per cent of one of these sugars, except glycerin, the growth of the organism is conspicuous, especially in the former three, and abundant gas evolution is observed (Table 3). 5. Fus. niveum strongly digests starch as well as sugars, and also digests cellulose and pectic matter though slowly. It may be recognized from these characters that the fungus is one of the soil inhabiting pathogenes, and that when it attacks the host plant it grows well in the water conductive tissue, and also invades the parenchymatous elements easily, destructing these tissues and consuming diiectly the reserved materials. 6. Fus . niveum ferments glucose with abundant evolution of gas when cultured in the media containing 2 to 5 per cent of glucose. The fermenting action is much strong at the optimum temperature for growth of the fungus (Table 5). 7. It is found that the amount of gas evolved depends on the sugar content of the culture media, and also on aerobic condition of culture. In higher contents of sugar e. g. 2 to 5 per cent of glucosethe evolution of gas is abundant under aerobic or semi-anaerobic condition, while no gas is evolved under highly anaerobic condition. In lower contents of sugare. g. 0.I per cent of glucosethe total amount of gas in the closed tube rather decreases under aerobic or semi-anaerobic condition (Table 6, 7, 8). When sucrose is applied, this decrease is observed in the case less than 0.02 per cent of sugar (Table 9, 10). 8. The quantity of sugar decreased in the glucose media, when cultured at 29°C to 30°C, is very conspicuous, and after thirty days it decreased to 0.4 per cent when 2 per cent glucose medium was used, and to 1.33 per cent when 5 per cent glucose BOAS medium was used (Table 11, 12). 9. The sugar content of the ascendin g sap of watermelon was tested to see whether or not the amount of sugar is enough for the fungus to evolve gas. It was found that the content of sugar of the sap is much higher by night than by day time (Table 13, 14), and is variable by the exudation quantity of sap per unit time, and by the lapse of time after cutting the stems. The maximum values thus obtained were 0.038 per cent and 0.087 per centtotal water soluble sugars presented as glucose? (Table 15). These values were of the sap obtained soon after cutting the stems, so that the exact values of the sugar contents of the true ascending saps will be smaller than these, because the saps tested are the mixtures of the true conductive waters and the exduation juices from the wounded surfaces other than vessels. From the preceding experiment (6) it is clear that Fus. n iveur is unable to produce gas from sugar of ascending sap, though the maximum content which may be higher than reaI value is considered, in such a semi-anaerobic condition as in the water conductive tissues.
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