part_of part of part of organ hematopoietic system mesoderm-derived structure hemopoietic organ Organ that is part of the hematopoietic system. organ of haematological system lymph organ hematopoietic system organ haemopoietic system organ haematological system organ organ of hematopoietic system lymphoid organ hematopoeitic organ hematopoeitic or lymphoid organ organ of haemopoietic system organa haemopoietica organ organ of organa haemopoietica