The breed of a fowl is judged of by the erectness of the crest, which is sometimes double, its black wings, reddish beak, and toes of unequal number, there being sometimes a fifth placed transversely above the other four. For the purposes of divination, those that have a yellow beak and feet are not considered pure; while for the secret rites of Bona Dea, black ones are chosen. There is also a dwarf[1] species of fowl, which is not barren either; a thing that is the case with no other kind of bird. These dwarfs, however, rarely lay at any stated periods, and their incubation is productive of injury[2] to the eggs.