Implacentalia
Pronunciation : Im`pla*cen*ta"li*a
Part of Speech : n.
Etymology : [NL. See In- not, and Placental.] (Zo?l.)
Definition : Defn: A primary division of the Mammalia, including the monotremes and marsupials, in which no placenta is formed.
pl.
Source : Webster's Unabridged Dictionary, 1913