14 



J. M. McGEE 



TABLE 1 



ALGA USED 



Iridaea laminarioides 



Tip of lamina 



Tip of lamina 



Gigartina mammillosa var. dissecta 



Tip of frond 



Tip of frond 



Lateral swelling 



Gagartina exasperata 



Young lamina (fresh) 



Young lamina (fresh) 



Young lamina (fresh) 



Young lamina (fresh) 



PER CENT SWELLING IN 



Sea water 



dIus NaOH 



N/100 







25.0 



10.0 

 50.0 

 10.0 



33.3 



16.6 



12.5 



3.5 



Sea water 

 HCl N/100 







31.0 



? 



15.0 

 22.2 



58.3 



20.8 



50.0 



7,1 



KNO3 and 



Citric acid 



N/100 



537.5 

 175.0 



60.0 

 60.0 

 17.0 



150.0 

 200.0 



158.6 

 132.8 



TABLE 2 



TABLE 3 



SUBSTANCE USED 



Plates composed of 9 grams agar and 

 extract from 10 grams of dry gigartina 

 exasperata 



Same as above 



THICKNESS 

 OF SECTS 



0.2286 

 0.2032 



PER CENT SWELLING IN 



NaOH 

 N/100 



809.0 

 910.4 



HCl N/100 



809.0 

 984.2 



Distilled 

 H2O 



2296.0 

 2460.6 



