In reviewing1 recently the literature of splenectomy, I was impressed with the very considerable variations in the cytology of the blood following the removal of the spleen in both man and animals. As this difference could not be explained by clinical history in the one case nor by experimental conditions in the other, a study of the changes in the dog's blood consequent on splenectomy was undertaken.
The literature of the subject is somewhat voluminous and may therefore be reviewed in two ways: first, from the point of view of physiological and experimental observation, and second, on the basis of clinical observation. At present the function of the spleen in relation to the formation or destruction of blood-cells is not definitely known. Howell2 states that the spleen is supposed to be the place of origin of erythrocytes. This is true in fetal life and