LOUIS FREEDMAN 9 



growth, both of these substances being present in blood. Rivers 

 and Poole 4 found that one of the substances was autoclave stable, 

 while the other was labile, and that the latter could also be found 

 in yeast. 



It was quite logical to surmise, therefore, that by heating 

 beef-heart infusions with larger amounts of norit, we might 

 extract a second substance or even more substances, the re- 

 moval of which would render the D.I.-G.S. solution inactive, even 

 on addition of peptone or autolyzed yeast. Accordingly two 

 portions of an undecolorized beef-heart infusion were boiled 

 with five and ten percent by weight of norit respectively ; but no 

 markedly different results were obtained on the yeast or bacterial 

 growth, as can be seen by comparing table III below with tables 

 I and II. 



This second unknown substance present in beef-heart, 

 thought to be in some way associated with blood, is therefore 

 not related to the class of B vitamine, as it is not extracted by 

 any of the adsorbing agents which have an affinity for this 

 class of vitamines. 



TABLE III. 



Growth of yeast and streptococci on beef-heart infusions, 

 decolorized with 5 and 10 norit. 



Net yeast Bacterial 



No. SUBSTANCE Growth* Growth 



in mm. 



1. 10 cc. Undecolorized beef -heart infusion .......... 17.5 + + + 



2. 6cc. " " " 



4- 5 cc. G. S. solution ......................... 18.0 4- + 4- 



8. 10 cc. Beef -heart infusion, decolorized with 5% 



norit ....................................... 1.0 



4. 5cc. Beef -heart infusion, decolorized with 5% 



norit, 4- 5 cc. G. S. solution ................... 1.5 



5. 10 cc. Beef -heart infusion, decolorized with 10% 



norit ....................................... 0. 



6. 5cc. Beef -heart infusion, decolorized with 10% 



norit, 4- 5 cc. G. S. solution ................... 0.5 



7. 10 cc. Beef -heart infusion, decolorized with 5% 



norit, and containing 1% peptone .............. 3.0 4- 



8. 5cc. Beef -heart infusion, decolorized with 5% 



norit, and containing: 1% peptone, -f- 5 cc. G. S. 2.5f 4- 4- 



9. 10 cc. Beef -heart infusion, decolorized with 10% 



norit, and containing 1% peptone ............. 2.5 + 



10. 5cc. Beef -heart infusion, decolorized with 10% 



norit, and containing 1% peptone, + 5 cc. G. S. 2.0f 4- 4- 



* For the yeast test, 1 cc. of each of the above mixtures was added to the standard 

 Nageli solution. 



f The slight decrease in activity here is due to the smaller amount of the beef-heart 

 infusion. 



