18 



CAKEY P. McCOKD 



to pineal activfty. The following procedures were employed. A single 

 paramecium was isolated until the reproduction of the third generation. 

 These resulting four individuals were separated and placed in different 

 media: (a) one in hay infusion; (b) one in hay infusion plus extract 

 of desiccated pineal gland, 0.05 per cent strength; (c) one in hay infu- 

 sion plus extract of desiccated muscle of equal strength, as a control mate- 

 rial, and (d) the fourth one was a variable control. These cultures were 

 maintained in a moist chamber for a fixed period (forty-eight or twenty- 

 four hours). At the expiration of that time the several cultures were 

 examined as to the number of reproductions. Almost invariably, the divi- 

 sions were more numerous in the pineal culture. For example, in one 

 forty-eight hour experiment, twelve offspring resulted from the plain hay 

 infusion, thirty offspring resulted from the hay infusion plus pineal ex- 

 tract and ten offspring from the hay infusion plus muscle extract. The 

 results from thirty-one consecutive experiments are grouped in Table I. 



TABLE I 



RECORDS OF DIVISIONS OF PARAMECIA, IN VARIOUS MEDIA. FIGURES INDICATE NUMBER OF 

 OFFSPRING FROM SINGLE PARENT ORGANISM IN EACH CASE 



The inference is, that pineal materials, when added to the culture 

 medium of the unicellular organism, paramecium, determines a more rapid 

 rate of reproduction. 



Injection Experiments. Immediate Results Following the Intrave- 

 nous or Subcutaneous Administration of Pineal Extracts. Unlike the in- 

 tense cardiovascular action of suprarenal extracts, or the uterine contract- 



