Each of 15 rabbits, under ether anesthesia, received an intracerebral injection of 1/2 cc. blood withdrawn from its marginal ear vein; they were killed with chloroform or ether 1-15 or 22 days after injection. Sections of the brains showed that the microglial cells are the chief elements concerned with phagocytosis of damaged brain tissue and in part with the removal of red blood corpuscles lying free in the brain substance. Large mononuclear cells, probably derived from the reticulo-endothelial system, are also concerned with the removal of red blood corpuscles. Microglial cells commence to remove products of degeneration within a few hrs. of wounding. Microglial cells may engulf red blood corpuscles in the early stages and contain pigment in the later stages. Astrocytes degenerate rapidly and only commence to recover and to wall off the wound at the end of 5 days. Astrocytes do not act as phagocytic agents. Red blood corpuscles may remain as such in the cerebral tissue for not longer than 12 days.