306 Canadian Record of Science. 



obtained. The conditions necessary are : First, a proper 

 temperature. That most suitable for them is between 

 45° and 70° F. Along with them are usually found the 

 Hcliozoa, the stalked Ciliata and some of the Flagellata. 

 If the temperature is raised to about 80° F., the Amoebae 

 quickly disappear and in their place countless numbers of 

 the free-swimming Ciliata make their appearance. The 

 water also becomes putrid. The method at present 

 adopted of securing and keeping them during the winter 

 months is the following : — In the Autumn the superficial 

 ooze from some fresh water pond is skimmed and placed 

 in a dish, the mouth of which is covered almost completely 

 to prevent* too rapid evaporation. Along with the ooze 

 some decaying vegetable matter and also some living 

 water plants. Of these I prefer Anacharis, although 

 Chara and some other common forms will do. A con- 

 siderable quantity of this is necessary to keep the water 

 fresh. 



The aquarium is then placed in a bright place where 

 there is plenty of light (though preferably not direct sun- 

 light), and in a cool place, best about 60° F. This then 

 can be left any length of time, and when they are 

 required, by squeezing a little of the decaying vegetable 

 matter on a glass slide, I have never failed to find one or 

 more of these interesting creatures. 



The conditions then, required, may be thus summarized : 



1. Some decaying vegetable matter. 



2. A sufficient amount of plant life to keep the water 

 from becoming putrid. 



3. A sufficiently low temperature which will also pre- 

 vent the bacteria of putrefaction from developing too 

 rapidly. 



By observing the above conditions one will seldom fail 

 to find Amoebae. 



