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Methods in Plant Histology 



gallons of water, the material may be soaked a dozen times before it 

 passes its usefulness. If material has been fixed in formalin, it may 

 be washed in sea-water not very thoroughly, but enough to remove 

 the pungent odor and then soaked in equal parts of glycerin and 

 water. Use only enough of the glycerin to make the specimens 

 flexible, not enough to make them wet to handle. In this way, 



FIG. 43. Cutleria multifida: photomicrograph from a preparation by Dr. S. Yama- 

 nouchi, showing a sorus of oogonia, each containing several eggs; thickness, 3/j.; stain, 

 iron-alum haematoxylin. X170. 



material of Laminaria, Macrocystis, Nereocystis, Postelsia, and other 

 large forms can be kept in condition for demonstration and will last 

 for years without any attention. When not in use, they should be 

 kept stored in a box. 



Cutleria.- -This alga deserves a place in any course in morphology, 

 if the course is thorough enough to permit the study of three members 



