The steep angle of the brain to spinal cord in jaundiced and spherocytic mice compared with normal, also seen as a sharp angle in the skull, suggests that erythropoiesis in hind region of skull may effect brain shape. Bouin's-fixed, whole brains are shown. Top, normal littermate to ja/ja #9; bottom, ja/ja mouse #9, 5.75 months. The arrow points to spinal cord at sharpened angle. Notice also the steeper slope of the cerebellum.