A LIPO-GEL REACTION. 23! 



directly from the testes of animals of various ages and always 

 obtained a positive reaction. Material from the testis may be 

 supposed to contain a larger percentage of spermatocytes or 

 cells in other stages of spermatogenesis than material taken 

 directly from the epididymis or vas. No difference can be seen 

 in the reaction however. 



(/) Spermatozoa. Spermatozoa taken from any part of the 

 epididymis, testis, vas deferens, or seminal vesicle always yield 

 the reaction under the conditions previously described. Sperma- 

 tozoa have been ground in a mortar for ten minutes, then mixed 

 with salt solution, centrifuged, and filtered through four sheets 

 of filter paper. The fluid obtained in this fashion was observed 

 under the microscope; no spermatozoa or fragments of sperma- 

 tozoa could be distinguished. Such a fluid however gives the 

 reaction both with untreated follicular fluid and with follicular 

 fluid that has been agitated, centrifuged, and filtered. 



Thus all of the experiments to this point show that a coagulum 

 is produced normally by a particular substance present in the 

 follicular fluid, a product of the ovary, when mixed with products 

 of the testes, especially the spermatozoa. The follicular sub- 

 stance is thermolabile and resistant to the action of mechanical 

 factors. The experiments also show that the spermatozoa as 

 formed cells are not essential to the reaction. 



Up to this point in the experiments the reaction appeared 

 to be perfectly specific: only products of the ovary act upon 

 products of the testes. 



5. Role of lipoids. Through certain microscopical observa- 

 tions, however, a new line of experimentation was suggested 

 to me. Whenever spermatozoa treated with sodium chloride or 

 with follicular fluid were studied under the microscope it was 

 noted that after a short time the field of the microscope became 

 filled with numerous small droplets, refractile, perfectly round, 

 of the dimensions of cocci, and engaged in active brownian 

 movements. The droplets increase in number with the degree of 

 concentration of the salt solution. 1 When the suspension begins 



1 This phenomenon of drop production by action of salt solution is very clearly 

 explained in Aschoff, L., "Zur frage der tropfigen Entmischung," Verh. deutsch. 

 path. Gesell., 17, Tagung Munchen, 1914, p. 103-109. The influence of NaCl 



