The stage at hatching for egg-brooding frogs, also called marsupial frogs, is determined by the amount of yolk in each egg, which in turn reflects the number of eggs produced per clutch. Species in which the eggs hatch as small tadpoles produce 100 or more ova, each ca. 2 mm in diameter. Where froglets emerge directly, only about six ova are produced, each ca. 10 mm in diameter.