FKESH WATER LIFE. 



By J. McCi. Baxter, M. I). 



^^0 study life as it actually exists in fresh water, that is, to 

 f§) watch the minutia? of everyday existence in the natural 

 habitat and surroundings of the minute forms of fresh 

 water life, seems, with the means that we have at our disposal, an 

 impossibility. What scientist is able to closely inspect with 

 the microscope the career of a closterium venus or a difflugia 

 j)yraformis in the midst of a raging stream at the time of a spring 

 freshet? And yet I have found them both in such a situation. 

 It is marvellous that such helpless forms can sustain life in such 

 untoward circumstances. One would think that they must in- 

 evitably be swept away to an ocean grave, and no doubt many 

 are, but others seem to thrive and obtain tlieir nourishment even 

 under such trying circumstances. 



While thinking over these facts the thought arose that it 

 might be a point of some inierest to test how far these forms of 

 life would offer resistance to untoward circumstances and still 

 life be sustained. For instance, taking forms that are found in 

 pure running water and keeping them in glass vessels, with or 

 without food, with no change of water for different lengths of 

 time, and then find out how many and what kinds would sur- 

 vive. 



With this object in view a number of samples of fresh water 

 containing different forms of life, animal and vegetable, were 

 prepared under the following conditions and kept for examin- 

 ation at different times. 



Specimen No. 1. 



This was collected June 8th, 1903, and examined xMay 13th, 

 1904. It was not examined when taken to see what life there 

 was in it then, but it can be compared to other specimens taken 

 in the same place and examined at once in order to compare 

 and see what forms persisted and what ones perished. The cir- 

 cumstances against which they had to contend are these. The 

 specimen was contained in a pickle bottle and stood on the office 



