1898.] MIC1108C0PICAL JOURNAL. 157 



Can Amoeba be Formed from Bacillaria? 



By Arthur M. Edwards, M. D., 



On the tenth of last July I collected in a two ounce 

 bottle some algao in the salt waters of the harbor of 

 New York. The water was ordinary salt water of the 

 ocean. The bottle was about full, holding nearly two 

 ounces. I took it home, examined it and found it to be 

 Melosira nummuloides, a common species. I could not find 

 any other species of Bacillaria and was about to throw it 

 out. I hesitated for a while. I therefore took it out of the 

 bottle leaving a very small quantity behind and thought 

 I would grow it in the water and see what it came to. 

 I put the bottle aside, a two ounce salt mouthed bottle it 

 must be remembered, on my desic where I could examine 

 it from time to time with a microscope, using a quarter 

 inch objective and a one inch occular. I had a power of 

 about 400. My desk was at the east side of the house so 

 that I had sunlight for a short time in the morning. The 

 bottle was not exposed to the sun's rays so that it did not 

 get very warm. We had hot weather nevertheless and 

 although my window was always open the thermometer 

 went up to nearly 100° and as there was no cork in the 

 bottle the water rapidly evaporated. Perhaps if I had 

 not had several years experience in growing Bacillaria 

 and other things in bottles I would expect the water to 

 become rank but it did not. There was not very much 

 vegetable or other matter in it, and water alone cannot 

 decay. It evaporated and evaporated. The level gradu- 

 ally became less until it had evaporated nearly to one 

 quarter and was very salty. The quantity was so very 

 small that I could not test it chemically, but it was brine. 

 I wanted to again see if Melosira nummuloides would 

 change into Melosira borreri as I had seen it do many 

 years before (Published in Grovillia). I took some out on 



