CHAPTER XV 

 PHAEOPHYCEAE. BROWN ALGAE 



The Phaeophyceae, or brown algae, are almost exclusively 

 marine. They include a great variety of forms, ranging from delicate 

 filaments to coarse, leathery plants a hundred feet in length. There 

 are no unicellular members. 



For fixing marine algae, fixing agents should be made up with sea- 

 water, never with fresh water, and the washing should be done with 

 sea-water; but fresh water should be used in making the series of 

 alcohols. When the Venetian turpentine method is to be used, the 

 fresh water is used first in making up the 10 per cent glycerin. 



For habit work, material may be put into formalin about 6 c.c. 

 commercial formalin to 100 c.c. of sea-water and kept there indefi- 

 nitely. If it is desired to transport large quantities of coarse forms, 

 the material may remain in this solution for a week and may then be 

 removed from the liquid and packed in closed pails or tubs or any 

 water-tight containers. After reaching its destination, the material 

 should be put into formalin again. 



For material to be mounted by the Venetian turpentine method, 

 6 to 10 per cent formalin (always in sea-water) is a good fixing agent. 

 Wash in sea-water for 1 hour, then in equal parts sea-water and 

 fresh water for \ hour, then in fresh water \ hour. The material 

 is now ready for staining in aqueous stains, or for the 10 per 

 cent glycerin, if alcoholic stains are to be used. 



The following formula by Flemming will also give good results, 

 both for the Venetian turpentine method and for the paraffin method: 



Chromic acid 1 g. 



Glacial acetic acid 0.4 c.c. 



Sea-water 400 c.c. 



Fix 24 to 48 hours and wash 24 hours in running sea-water. A 

 convenient washing-box can be made from an ordinary washtub. 

 Bore a dozen f-inch holes in the bottom; insert rubber tubes 6 



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