INTRODUCTORY
About a year ago, during the course of studies in the albino rat (Mus norvegicus-albinus) carried on under the direction of Dr. Alfred Stengel, on the relation of the spleen to the other glands of internal secretion, it was thought worth while to note incidentally any blood changes that might occur after splenectomy, since no references to such observations on the rat could be found in the literature. Among the first observations a few unusual and interesting phenomena were noted, which seemed to make a somewhat systematic study worth while.A fairly complete bibliography of the literature up to 1914 of the blood changes after splenectomy may be found among the references given by Meyer.1 The most important work since that time is that of Pearce and his collaborators.2Observations on man, dogs, rabbits, goats, sheep and other animals have shown that removal of the spleen is