n. pl.
[NL. See
(Zoöl.) A primary division of the Mammalia, including the monotremes and marsupials, in which no placenta is formed.
| Dictionary: Im·pla·cen·ta·li·a |
[NL. See
(Zoöl.) A primary division of the Mammalia, including the monotremes and marsupials, in which no placenta is formed.