30 



thecia, while many others were developing and were still white. The 

 compauiou tube was free from perithecia and remained so until the end 

 of the experiment (76 days). At this time the fungus in the tube which 

 had received only one-half as much alkali had developed perithecia all 

 over the potato, but they were still immature and either colorless, yel- 

 lowish, or pale brown. 



(3) In 40 days on rice with bicarbonate of soda there was no pro- 

 duction of perithecia, although the tube had been copiously inoculated 

 with ascospores. The tube contained 10 c. c. of rather dry boiled 

 rice, to which was added 2 c. c. of a cold saturated solution of the 

 sodium bicarbonate in water. In 5 days there was only a very feeble 

 white growth. At the end of 40 days the fungus had grown sparingly 

 over most of the rice grains in the upper half of the tube, and micro- 

 conidia were present, but the rice had not changed color and no peri- 

 thecia could be found. 



OTHER BIOLOGICAL PECULIARITIES. 



In addition to what has already been said, there are a few other 

 peculiarities which may here be mentioned. 



The fungus in all its varieties is a strict aerobe. Up to this time the 

 writer has never been able to find any substance in the presence of 

 which it will grow in the closed end of fermentation tubes. It seems 

 entirely unable to obtain its respiratory oxygen from food substances. 



The melon fungus is able to obtain its nitrogen from asparagin. In 

 carbohydrate foods nearly destitute of nitrogen, and in which the fun- 

 gus could make but a very feeble growth, it at once made an excellent 

 growth on adding a small fragment of asparagin. 



Old rice cultures of the melon fungus gave off" a peculiar, rather 

 pleasant, aromatic odor when boiled in water. 



On boiled seeds of the cowpea the melon fungus grew vigorously and 

 developed a peculiar musky, pungent odor, which was observed as soon 

 as the tubes were unplugged and was quite unlike that just mentioned. 



The melon fungus grew vigorously on potato and nutrient agar which 

 was sterilized with a large quantity of sulphur dust. 



The melon fungus grew on nutrient agar in the presence of large 

 quantities of caustic lime and of carbonate of lime. 



The melon fungus also grew (at first very slowly and in small 

 patches) in a tiask of boiled rice in the presence of very large quanti- 

 ties of sodium carbonate (one-half pound of rice cooked with about 300 

 c. c. of distilled water and 100 c. c. of a saturated solution of sodium 

 carbonate, saturation temperature 25© C). The quantity of alkali was 

 sufficient to make the rice quite yellow. 



In a test-tube culture, the cowpea fungus grew on a cylinder of potato 

 which had been boiled with 2 c. c. distilled water and 1 c. c. saturated 

 solution of sodium carbonate (25° 0.). After steaming, one-half of the 

 fluid was poured off, so as to expose part of the potato to the air, and 

 the surface was inoculated with ascospores. 



