In a number of experiments caffein was introduced into the peritoneal
cavity. Rabbits of different varieties receiving a diet of oats or
carrots were employed for this purpose; food and water were given ad
libitum. The minimum doses required to induce symptoms or cause death
in these animals were determined; tests with caffein were also made on
young rabbits in order to study the influence of age on the resistance
to this substance. The results are shown in the following experiments: