208 ELEMENTARY PHYSIOLOGY. [xiX. 



B. GLYCOGEN. 



1. Give a rabbit a full meal 1 and about six hours 

 afterwards decapitate it, cut out the liver as 

 rapidly as possible, disregarding the bleeding. 

 Remove the gall-bladder and cut up one half 

 of the liver into small pieces and throw them 

 straightway into about 200 times their bulk of 

 water which is already boiling. (Place the other 

 half in the warm, keeping it moist (cp. 3).) In 

 about five minutes, when the pieces in the boiling 

 water are all thoroughly coagulated, and the 

 ferment has been destroyed, remove them and 

 pound them in a mortar into a paste with sand ; 

 mix this paste with the water previously used, 

 just acidulate with dilute acetic acid (to ensure 

 the complete coagulation of albumin) and boil 

 for a few minutes. Let it stand till the coagulated 

 proteids have settled, and filter the milky fluid 

 through a coarse filter. The sediment may be 

 squeezed in linen, and the expressed fluid thrown 

 on the filter. The opalescent filtrate is a crude 

 infusion of glycogen. The above will afford ma- 

 terial for several students. 



If it contains much proteid material, it should be 

 carefully neutralized, boiled again, and filtered. 



2. a. Place a few c. c. of the fluid in a test-tube, and 



add a drop or two of iodine solution. A port- 



1 The rabbit may be fed on bran and carrots. 



