Some globular clusters, like Omega Centauri in the Milky Way and G 1 in M 31, are extraordinarily massive, with several million solar masses () and multiple stellar populations. Both can be regarded as evidence that supermassive globular clusters are in fact the cores of dwarf galaxies that are consumed by the larger galaxies. About a quarter of the globular cluster population in the Milky Way may have been accreted along with their host dwarf galaxy. More than 60% of the globular clusters in the outer halo (more than from the center) of the Andromeda Galaxy were likely accreted in a similar fashion.