資料來源 : pyDict
哺乳類
資料來源 : Webster's Revised Unabridged Dictionary (1913)
Mammalia \Mam*ma"li*a\, n. pl. [NL., from L. mammalis. See
{Mammal}.] (Zo["o]l.)
The highest class of Vertebrata. The young are nourished for
a time by milk, or an analogous fluid, secreted by the
mammary glands of the mother.
Note: Mammalia are divided into three subclasses; -- I.
{Placentalia}. This subclass embraces all the higher
orders, including man. In these the fetus is attached
to the uterus by a placenta. II. {Marsupialia}. In
these no placenta is formed, and the young, which are
born at an early state of development, are carried for
a time attached to the teats, and usually protected by
a marsupial pouch. The opossum, kangaroo, wombat, and
koala are examples. III. {Monotremata}. In this group,
which includes the genera {Echidna} and
{Ornithorhynchus}, the female lays large eggs
resembling those of a bird or lizard, and the young,
which are hatched like those of birds, are nourished by
a watery secretion from the imperfectly developed
mamm[ae].
資料來源 : WordNet®
Mammalia
n : warm-blooded vertebrates characterized by mammary glands in
the female [syn: {class Mammalia}]