Abstract
1. The intravenous injection of trypsin in dogs results in a shock similar in many respects to anaphylactic and peptone shock. 2. The injection is followed by a marked rise of serum protease and lipase. 3. The antiferment usually shows a distinct drop in titer, with a recovery following in from four to twenty-four hours. 4. The non-coagulable nitrogen shows no constant alteration, but is never greatly changed in amount. 5. Inactivated preparations were in some respects followed by symptoms similar to those following the injection of the active preparation. 6. Subcutaneous and gastric absorption was practically without effect. 7. Intestinal absorption was followed by an increase in serum protease without evidence of intoxication, or by typical symptoms of acute poisoning. 8. The leucocyte curve bears no constant relation to the serum protease or lipase.