The patients in this series are, with few exceptions, boys and girls ranging in age from 10 to 20 years, all inmates of an institution and thus under continuous medical supervision. They spend a great part of the summer in the open, working and playing daily where they are constantly exposed to poison ivy and poison oak. During the previous summer a good deal of time was consumed in treating patients who had cases of poison ivy by local applications day after day, without any apparent results. Therefore, in the spring of this year, hearing of the work of Dr. Albert Strickler of Philadelphia, we obtained some of the antigen and tincture used by him and decided to give it a fair trial here, where numerous cases are always inevitable. We did not follow exactly the method of treatment and of desensitization as directed by Dr. Strickler because of the