monotremata
Mon`o*trem"a*ta, n. pl. Etym: [NL., fr. Gr. (Zoöl.) Defn: A subclass of Mammalia, having a cloaca in which the ducts of the urinary, genital, and alimentary systems terminate, as in birds. The female lays eggs like a bird. See Duck mole, under Duck, and Echidna.