In a paired feeding experiment the effects of vitamin B1 deficiency and of restriction of food intake have been compared. In both groups of animals the number of cases of paralysis and the number of deaths were less than in a control group on an unrestricted amount of the complete diet. The maximum difference occurred on the 15th day after inoculation. The incidence of paralysis and death in the vitamin-deficient group was also less than in the paired restricted group. The maximum difference occurred on the 17th day following inoculation, after which the difference gradually became less. At the end of the experiment (28 days) there was a slightly greater number of deaths in the restricted group than in the vitamin-deficient group. Apparently the effect of vitamin B1 deficiency on the action of the virus of poliomyelitis in the mouse is not due solely to the resulting anorexia.
From the 3rd to the 25th day after inoculation the animals were examined at hourly intervals throughout the day and night. On the 26th and 27th days they were examined every 3 hours. Except for two mice in the unrestricted group dying before the hourly examinations were begun, peripheral paralysis was observed in every animal which died.