Scientific Proceedings (84). 



ments no minimum amount has been determined as yet. The 



data at hand, however, figured on the same basis as follows 



Rat No. 4. In 10 days received 38 gm. Lloyd and 116 gm. casein 



diet, i. e., 2 per cent, vitamine. The gain in weight was 13 gm. 

 Rat No. 5. In 10 days received 20 gm. Lloyd and 94 gm. casein 



diet, i. e., 1.2 per cent, vitamine. The gain was 15 gm. 

 Rat No. 20. In 13 days received 13 gm. Lloyd, 433 gm. farina and 



240 gr. condensed milk, i. e., 0.11 per cent vitamine. The 



gain was 20 gm. 



Rat No. 31. In 14 days received 7 gm. of Lloyd, 450 gm. farina 

 and 210 gm. boiled milk, i. e., 0.063 P er cent, vitamine. The 

 gain was 15 gm. 



Rat No. 39. In 14 days received 3^ gm- Lloyd, 450 gm. farina 



and 210 gm. boiled milk, e., 0.031 per cent, vitamine. 



The gain was 21 gm. 

 John G. In 21 days received 42 gm. Lloyd, 630 gm. farina and 



1,280 gm. condensed milk, i. e., 0.13 per cent, vitamine. The 



gain was 588 gm. 

 10 other babies gained, but in no case on less than 0.13 per cent, 

 vitamine. From these results however it seems hardly a desirable 

 method of figuring vitamine needs. Per cent, of vitamine nitrogen 

 would probably be a better basis. 



II. Possibility of a Colorimetric Method of Determining 



Dosage. 



In one of his papers Funk noted that the fraction containing 

 the vitamine gives the blue color reaction with the Folin-Macallum 

 uric acid reagent. This fact suggested another possible method of 

 determining dosage. Experiments to date with pancreatic extract 

 have given the following facts: 



1. The water extract gives the color reaction. 



2. The extract after treatment with the Lloyd reagent (50 

 gm. to the liter) and removal of the Lloyd by filtration, still gives 

 the reaction but with a marked reduction in intensity. 



3. The Lloyd reagent from the first shaking gives the reaction. 



4. The Lloyd reagent shaken with the filtrate from 3 gives the 

 reaction but with marked reduction in intensity. 



5. An alkaline and an acetic acid extract of the activated 



