30 MARY DRUSILLA FLATHER. 



I'.ach of these preparations produces a specific efiV.-t 



n higher organisms, the first contracting the arteries and 



Mlaries, raising the blood pressure, and stimulating the heart, 



second acting as a powerful stimulant to growth, and the 



third slightly increasing the blood pressure. The object of the 



following experiments is to discover whether these glandular 



products have an equally specific effect upon the pulse frequency 



of the contractile vacuole. The preparations were made up 



with distilled water into solutions of varying strengths, i- 



2,000,000, 1-1,000,000 and 1-200,000. Observations were made 



immediately after adding drops of a solution to the culture 



medium. The results of the experiments are shown in the tables. 



TABLE I. 



EFFECT OF ADRENALIN, 1-2,000,000. 



The increase in pulse frequency after the addition of one drop 

 of adrenalin, 1-2,000,000 is insignificant. No greater incn.iM 

 occurred at any time within two hours after the treatment with 

 adrenalin. 



Fig. i represents graphically the effect of adrenalin upon tin- 

 vacuoles of a Paramecium in an abnormal physiological condition, 

 produced by some unknown factor. Treatment with our drop 

 of adrenalin, 1-2,000,000 solution did not prevent the rapidly 

 diminishing frequency. One drop of adrenalin, 1-1,000,000 

 produced an immediate quickening in both vacuoles, 



