Rhodophyceae 



191 



Fix 24 hours, changing the fixing agent 2 or 3 times. Wash 24 

 hours in sea-water. 



If carefully applied, the following is a good method: Put the 

 material into 5 per cent glacial acetic acid (in sea-water) and watch 



t 



Ifl; <", 



FIG. 49. Polysiphonia fibrillosa: young cystocarps showing carpospores and the 

 irregular fusion cell beneath; photomicrograph from an iron-alum haematoxylin prepara- 

 tion by Dr. S. Yamanouchi. X125. 



it. As soon as the vigorous effervescence begins to subside, rinse 

 in sea-water and transfer to Flemming's weaker solution, and fix 

 24 hours. Iron-haematoxylin is best for figures, but for general 

 structure the safranin, gentian-violet, orange combination gives 

 beautiful results. 



