CHAPTER XVIII 



PHAEOPHYCEAE. BROWN ALGAE 



These algae are almost exclusively marine. The plant body ranges 

 from delicate filamentous forms to coarse, leathery plants 150 feet in 

 length. There are no unicellular members of the Phaeophyceae. 



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

 water, never with fresh water ; and the washing should begin with sea 

 water. In general, wash in running sea water 24 hours. 



For washing, especially when there is a large class, it is not likely 

 that there will be a sufficient number of faucets. A convenient wash- 

 ing-box can be made from an ordinary washtub. Bore a dozen f-inch 

 holes in the bottom, insert rubber tubes 6 inches long, and in the end 

 of each tube place the glass part of a pipette. The tub may be elevated 

 by nailing three narrow boards to the sides so as to form a tripod. 

 Place the bottles or cans of material under the pipettes and let sea 

 water flow into the tub. The outlets which are not in use can be closed 

 by placing clamps on the rubber tubes. 



After the washing in sea water, wash for 1 or 2 hours in a mixture of 

 equal parts of sea water and fresh water; then, for 1 hour in fresh 

 water. Use fresh water in making up the alcohols. 



During cold weather, large coarse forms, like Fucus, Nereocystis, 

 Laminaria, etc., can be shipped from either coast to the Mississippi 

 River, without any fixing. Roll the plants in a dozen thicknesses of 

 newspaper, around this put oiled paper, and then wrap in oilcloth. Upon 

 arrival, the material can be studied while it is still alive. Rotation of 

 the egg and fertilization in Fucus has been studied satisfactorily in 

 material shipped from the coast to the Mississippi River. 



For habit work, material can be put into formalin — about 10 c.c. of 

 formalin to 90 c.c. of sea water — and kept there indefinitely. Material 

 should be washed well in water before handing it to a class, because 

 formalin is irritating to the eyes and nose, and even to the hands. 

 Material, which is not used, can be put back into the preservative. 



Large forms, like Nereocystis, can be soaked in the formalin mixture 

 for a week, and then the preservative may be poured off and the mate- 

 rial can be rolled up, as directed for the hving material, and shipped to 



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