1. The histological changes of the bone marrow in fasted and rice disease pigeons are essentially the same.
2. The histological changes of the bone marrow in pure vitamin B deficiency consist of degeneration and edema and slight endothelial proliferation of the small vascular channels, but with active hematopoiesis.
3. The anemia of rice disease in pigeons is in large part a starvation anemia and not directly related to vitamin B deficiency.