230 GREGOR T. POPA. 



of blood. Later, however, I took very minute precautions l to 

 avoid admixture of blood and found that the reaction was 

 always obtained in the complete absence of blood. I also while 

 at the slaughter-house repeatedly mixed blood from the jugular 

 vein with follicular fluid and never obtained the reaction. 2 It 

 thus appears that the blood, and by implication the various 

 constituents of the blood are not involved in the reaction. 



(b) Proteins. A series of experiments performed with egg 

 albumin gave completely negative results. This result would be 

 expected from the negative rinding with blood. Another proof 

 that proteins are not involved may be derived from the fact that 

 the reaction fails at a temperature of 56 C., although the fluid 

 so heated and incapable of producing the reaction still contains 

 proteins which do not coagulate until a temperature of 72 C. 

 is reached. 



(f) Sodium chloride. This salt and salts in general never 

 produce the coagulum when mixed with either spermatozoa alone 

 or follicular fluid alone. 



(d) Granulosa cells. Follicular fluid was centrifuged and the 

 clear fluid filtered to remove all cells. The absence of cells was 

 verified by microscopic examination. The clear fluid was then 

 violently agitated with glass granules for fifteen minutes with 

 the idea of possibly altering the degree of dispersion of colloidal 

 material that might be present. The fluid was then filtered 

 through four sheets of soft filter paper. The fluid so treated 

 still produces the reaction, indicating that cells or other formed 

 constituents are not responsible for the coagulum. It may be 

 mentioned here that filtered follicular fluid was always employed 

 in all experiments. 



(e) Spermatocytes. I was unable to separate the spermato- 

 cytes from the spermatozoa and therefore could not test their 

 effect on the reaction separately. But I used material taken 



1 Ovaries taken directly from the body; washing them very carefully in labora- 

 tory before experiments; after that drying by absorbent paper; dissecting the 

 follicles with a sharp knife until they appear like transparent vesicles. Only after 

 that treatment puncture of follicles. 



2 In this case the anticoagulant effect of the sperm or of follicular fluid can be 

 explained by the properties of NaCl and fatty substances, both able to stop the 

 normal coagulation of the blood. Gilbert et Weinberg. "Traite du sang," 1913- 

 1921, p. 15-16. 



