EFFECT OF FOOD ON GROWTH OF PARAMECIUM CAUDATUM. 89 



A series of experiments was tried with mixtures of pituitary 

 and suprarenal solutions in the basic food substance. The 

 results indicate that the rate of division is greatly reduced. 

 Sometimes the Paramecia would exist for seven days without 

 dividing. 



At this point in the work the control culture medium was 

 changed from hay infusion to .2 per cent, malted milk. Another 

 pedigreed race was started which had been in malted milk for 

 several months. The solutions used were in two proportions- 

 first, control line two drops of malted milk, experimental line 

 one drop of malted milk, one drop of pituitary; second, control 

 line three drops of malted milk, experimental line one drop of 

 malted milk, and two drops of pituitary. 



TABLE XI. 



PITUITARY AND MALTED MILK SOLUTIONS. Daily Division Averaged for Nine 



Days. 



In both experimental lines the Paramecia died after swimming 

 about normally for five days without dividing. In no way can 

 these results be correlated with the previous similar experiment 

 where the basic food was hay infusion. 



Solutions of suprarenal were the same as those above for 

 pituitary. 



TABLE XII. 



SUPRARENAL AND MALTED MILK SOLUTION. Daily Division Average for Nine 



Days. 



There is an increase in division rate when Paramecia are fed 

 suprarenal solution whether the basic fluid is hay infusion or 

 malted milk. 



