and Laboratory Methods. 2411 



Algae and Fungi for Class Work. 



In the April number of this Journal Miss Mary A. Hickman reports the 

 successful rearing of Coleochaete in the laboratory, and says that " it seems 

 probable that Coleochaete may be obtained for laboratory work by this method," 

 My experience shows that in this opinion she is correct. I have raised this alga 

 in abundance without trouble ; in fact, it is one of the most likely to occur in 

 culture jars, or bottles filled with water plants. In one small bottle that stood 

 on my table for several months during the past fall and winter, almost the whole 

 side away from the light (which was rather strong) became covered with the cir- 

 cular discs of Coleochaete, which remained in healthy condition for a long time. 

 Also in a large culture jar containing Myriophyllum and other plants a great 

 amount of coleochaete appeared, here likewise on the less illuminated side, 

 although the jar was a considerable distance from the window. It is generally 

 difficult to remove this algae from the glass without breaking it badly ; and a 

 good method to get it in nice condition for study would no doubt be to hang 

 cover-glasses against the shady side of such culture dishes and allow the alga to 

 grow attached to them. They could then be removed and studied without 

 disturbance. 



To get Ulothrix zoospores take some of the alga from moist ground (not 

 immersed), and place it in the bottom of a small jar of water. By the next 

 morning zoospores will probably appear in abundance. I have taken in nearly 

 dry Ulothrix which, when treated in this way, produced zoospores from almost 

 every cell. According to my experience zoospores of any alga are best ob- 

 tained by introducing a sudden change in environment. 



Another instance of zoospore production being induced by changed condi- 

 tions was found in experimenting with Schizomeris. A small bottle of this alga 

 had been in the laboratory for a long time and had become somewhat foul. 

 During this time no zoospores were produced, but when the alga was at last 

 removed to a bottle of fresh water, an immense number of zoospores were 

 formed in less than twenty-four hours. 



It is remarkable how long some algae can retain their vitality under most 

 adverse conditions. As an illustration, a small vial about three inches high full 

 of water containing a little Nostoc was tightly stoppered and packed away for 

 about twenty months, and when again examined the Nostoc was still fresh and 

 brightly colored, and showed no signs of bad treatment. 



When a bottle of algae is brought into the laboratory there is usually a 

 fouling of the water due to bacteria, which is hard on the plants, but if the 

 culture is let alone it soon clears up and the algae renew their growth, and live 

 and prosper for a long time without further attention. By this method I have 

 had no trouble in raising young plants from the zoospores of Vaucheria, 

 Ulothrix, Oedogonium, Aphanochaete, Coleochaete, Schizomeris, and Stigeoclo- 

 nium. Tetraspora and Euglena were also cultivated repeatedly. 



Any of the cells of Tetraspora seem capable of swarming under proper con- 

 ditions. In one case a number of nearly quiet cells in jelly were put in the sun 



