[Vol. 2 



826 



ANNALS OF THE MISSOURI BOTANICAL GARDEN 



forms. In the filamentous forms he showed the presence of 

 oxidases by the formation of colored granules within the cells 

 surrounded by these reagents. Eeed concludes that oxidases 

 of specific oxidative ability are very generally present in the 



algae, and where negative results 



are obtained, either the 



j specific compound is not present or other factors 

 such as the destruction of the oxidase equilibrium of 



the cell unon crushin 



Catal 



Both fresh and air-dried tissue were used fo 



catalase demonstration. In a preliminary series, the addition 

 of 5 cc. of 3 per cent hydrogen peroxide to about a gram of 

 fresh crushed algal tissue showed evolution of oxygen in all 

 cases except one, that of Mesogloea. Later, a series (table xix) 



TABLE XIX 



CATALASE ACTIVITY OF CERTAIN ALGAE 



Alga 



Number cc. 0- evolved at 21 .5°C. 



2 minutes 



5 minutes 10 minutes 



Ascophyllum 



Laminaria 



Viva 



Agardhiella 



Chondrus 



Rhodvmcnia 



.3 

 1.4 

 0.0 



.2 

 3.3 



.4 



.9 



3.7 



22.6 



.9 

 2.3 

 0.0 



.4 

 4.6 

 2.0 

 1.4 

 5.9 



.9 

 2.3 

 0.0 



.5 

 5.6 

 2.5 

 2.0 



Potato leaf tissue 



8.2 





^^™ ^^H fl ^L^ 



* * V V 



■ • ■ • 



was set up in which 1 gram of powder was placed in 125 cc. 

 Erlenmeyer flasks, 10 cc. of 3 per cent hydrogen peroxide 

 added, and the oxygen evolved collected in a gas burette over 

 water. The flask in which the action was taking place was 



shaken every 15 seconds, and the volume of oxygen evolved 

 read at the end of 2, 5, and 10 minutes. The temperature of 

 the room was practically constant during the experiments and 

 no especial precautions were taken to control the temperature 

 of the flask other than keeping the hands away from it dur- 

 ing the action. The results are not meant to be quantitatively 

 exact, but they do give the relative catalase activity of the 

 several forms. In addition, air-dried potato leaf tissue that 

 had been in the laboratory about the same length of time as 

 the algal tissue was tested for comparison. 



