144 THE VITAMINS 



teriological examination of the lesions has revealed the invariable pres- 

 ence of a Gram-positive coccus about one micron in diameter. This 

 organism under ordinary conditions is not pathogenic. It is incapable 

 of producing typical pellagrous lesions by injection, but when fed in 

 massive doses produces the characteristic syndrome readily in about 

 80 to 85 per cent of the test animals and eventually in all of them ; also 

 that concentrates of the preventive factor prepared from kudzu leaves 

 proved effective in prophylactic and curative tests, and have been 

 demonstrated to inhibit the growth of the causative organism in culture 

 medium. The amount of the protective factor required for complete 

 protection they thought to depend to some extent on the number and 

 virulence of the organisms ingested and the age and individual sus- 

 ceptibility of the animal. Young animals are much less susceptible than 

 older ones. They suggested that the pellagra-preventive factor may not 

 be identical with vitamin G, since the correlation between the degree 

 of protection against infection and the rate of growth was not always 

 good. 



Sherman and Sandels (1929, 1931) reported that, within certain 

 limits, the restriction of vitamin G (Bj) resulted in pellagra-like symp- 

 toms such as have been described by Goldberger and his coworkers and 

 by Chick and Roscoe, but in cases of almost complete deprivation of 

 vitamin G (Bj) death sometimes occurred without the development of 

 conspicuous skin symptoms. In general their experiments indicated 

 that in the condition resulting from almost complete deprivation of 

 this vitamin, the eyes, nose, mouth, alimentary tract, and perhaps kid- 

 neys were apt to show more pronounced abnormalities than the skin; 

 whereas with a less complete deprivation and a somewhat longer course 

 of the deficiency disease the abnormalities of the skin were apt to be- 

 come more prominent. They described their observations essentially as 

 follows : When vitamin G is decidedly lacking in the diet of rats of an 

 initial age of 4 weeks, growth is quickly retarded, usually within two 

 weeks, but the time interval is subject to considerable variation, depend- 

 ing upon the completeness with which the diet has been freed from 

 the factor in question and also, doubtless, on the previous diet of the 

 animal, inasmuch as the body is able to store appreciable amounts. 

 Several weeks later, soreness of the eyes appears with abnormal secre- 

 tion and a tendency to sticky lids, and to frequent rubbing and occa- 

 sional scratching of the lids by the animal ; in many cases the fur falls 

 out around the eyes, leaving bald inflamed lids ; usually the mouth 

 becomes sore, first with indications of excessive salivation, then inflam- 

 mation at the corners, sometimes progressing to an inflamed or 



