Acknowledgment is made of the assistance rendered by Dr. John R. Mohler, Chief of the Pathological Division, Bureau of Animal Industry, and his assistants, in performing the autopsies recorded in this report. I recommend the publication of the manuscript as Bulletin No. 148 of the Bureau of Chemistry.

Respectfully,

H. W. Wiley, Chief.

Hon. James Wilson,
Secretary of Agriculture.

THIS PUBLICATION may be procured from the Superintendent of Documents, Government Printing Office Washington, D. C., at 15 cents per copy

[CONTENTS.]

Page.
[Introduction]5
[Historical review of the literature on the toxicity of caffein]9
[Acute caffein intoxication]18
[Experiments on rabbits]18
[Subcutaneous injection]18
[Administration by mouth]26
[Injection into the peritoneal cavity]28
[Intramuscular injection]33
[Intravenous injection]37
[Summary]42
[Experiments on guinea pigs]43
[Subcutaneous injection]43
[Injection into the peritoneal cavity]47
[Administration by mouth]49
[Summary]52
[Experiments on cats]53
[Subcutaneous injection]53
[Injection into the peritoneal cavity]56
[Administration by mouth]57
[Summary]59
[Experiments on dogs]60
[Administration by mouth]60
[Subcutaneous injection]60
[Experiments on puppies]61
[Summary]62
[Chronic caffein intoxication]63
[Experiments on rabbits]63
[Experiments on dogs]75
[Discussion of results]91
[General summary and conclusions]95
[Bibliography]97