Plate I. Comparison of freeze-drying and chemical fixation. Both figures 

 show glycogen in rat liver as demonstrated by the reaction with periodate 

 (see Chapter 4) . Figure A shows the effect of fixing with 80 percent alcohol. 

 Figure B is a frozen-dried preparation. Figure A shows a polarised distri- 

 bution of glycogen, as though the cells had been centrifuged. Figure B 

 shows the physiological condition of the tissue. Preparations by L. G. Bell. 



