(XII) was determined in the Merck Institute for Therapeutic Research by Dr. Klaus Unna using a single dose curative assay7 on vitamin depleted rats. Some vitamin Be activity was found for this sample in dosages of 1000 and 2500 micrograms, but even the larger dose was not sufficient to produce cures which are effected by 50 micrograms of vitamin Be. Thus, the ethyl homolog possesses less than 2y0 of the activity of vitamin Be hydrochloride. ...
