THE PKESEKVATIO.V OF CHLOROPHYCEAE 



223 



(28) 3CLP Triple strenglli copper-lacto-phcnol. 



Cupric chloric! (crystals) G grains 



Copper acetate (crystals) 6 grams 



Lacto-phenol 88 grams 



The method used for testing the vahie of the different mixtures 

 gi\ en above consisted in putting a small amount of an alga in a 

 test tube containing 10 cc. of one of the mixtures, corking the tube, 

 and allowing the material to stand from two to three months in a 

 well-lighted room before examining. 



It was thought at first that some prediction could be made in 

 regard to the plasmolytic effect of the different mixtures if the 

 concentration of a sodium chlorid solution causing plasmoh'sis 

 were known. Table I, which gives the minimal percentage con- 



TABLE I 



Table showing that the plasmolytic equivalents obtained in one genus are not the same 

 as those in another. The numbers refer to the percentage concentration at which 



' plasmolysis takes place. When there was no plasmolysis the fact ivas noted by two 

 minus signs, incipient plasmolysis was designated by a plus and a minus sign, 

 and serious plasmolysis by two plus signs. 





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o 



e 



o 



1 

 < 



8 



■< 

 s 



m 

 z 

 o 

 > 



■< 

 es 

 >< 

 a 

 o 

 a 

 Z 



n 



s 



s 



S 

 o 

 c 

 o 

 a 

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NaCl 



3.5^ 



2.5-4 



2-3 



2-3 



1-2 



1-1.5 



CLP 





20(?) 



12 







below 2 



2CLP 





12 



4 





10 



below 2 



3CLP 







8 





4 



below 2 



XW 



+ + 



+ + 





• - 







FX 



+ + 









+ + 





R and P 



+ + 





+ + 







+ + 



centration of a sodium chlorid solution causing plasmolysis in 

 different species of algae, and the concentration of the different 

 preservative mixtures which produce the same effect, shows that 

 this expectation is not realized and that there is no relation be- 

 tween the plasmolytic action of sodium chlorid and that of the 

 mixtures in question. Thus, Vaucheria is plasmolyzed in 3.5 to 

 4 % sodium chlorid and Oedogoniuvi in 1 to 1.5 % sodium chlorid 

 solution, while Nieuwland-West's mixture causes plasmolysis 



