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noun-plural. That group of vertebrates which develops in its embryonic life the envelope called the amnion. It comprises the reptiles, the birds, and the mammals.

Same as Amnionata.

n. higher vertebrates (reptiles, birds and mammals) possessing an amnion during development

"Finally, the fetal membranes and their relations to the fetus and uterus are studied in their variations among the amniota."

craniate    vertebrate