Series A.
Guinea pig 41. Weight, 700 grams. Diet, oats.
April 1: 3.30 p. m., 4.5 cc 2 per cent caffein (130 mg per kilo) injected into peritoneal cavity. 5.35 p. m., symptoms present but no tetanus.
April 2: Found dead about 2 p. m., duration of life about 22 hours. Autopsy: Subcutaneous hemorrhage at the point of inoculation; serious exudate on visceral and parietal peritoneum with marked inflammation of peritoneum; portions of intestines showed slight enteritis.
Guinea pig 49. Male. Weight, 370 grams. Diet, oats.
April 1: 3.15 p. m., 2.5 cc 2 per cent caffein (135 mg per kilo) injected into the peritoneal cavity; 5.30 p. m., symptoms present; reflexes increased, but no tetanus. Guinea pig survived.
Guinea pig 47. Female. Weight, 550 grams. Diet, oats since about February 4.
March 17: 3.30 p. m., 3.5 cc 2 per cent caffein (127 mg per kilo) injected into peritoneal cavity; 4.35 p. m., increased irritability present, but not marked; 5.40 p. m., symptoms about the same as before.
March 18: 2.30 p. m., condition good; no symptoms. Survived.
Guinea pig 50. Female. Weight, 290 grams. Diet, oats.