Virginia Opossum (Didelphis virginiana)  KINGDOM Animalia PHYLUM
Chordata CLASS Mammalia ORDER Didelphimorpha FAMILY Didelphidae
Opossums are often thought to be big ugly rats. They are easily
recognized by their moderate size (total length with tail about
75 cm) scraggly appearance, with long, unkempt but soft, whitish
fur; a pointed, ratlike snout; and naked rounded ears. The long,
scantily haired, pink-tipped tail is also ratlike, although
somewhat prehensile. The sensory vibrissae (‘whiskers’) on the
head are exceptionally long. When a ‘possum opens its mouth,
however, the rat resemblance disappears, as the teeth look much
like those of a carnivore, except more of them, 50 to be exact.
This is the largest number of teeth of any North American
mammal.  Opossums are marsupials, members of a subclass of
mammals distinct from all others in North America, which are
placentals. The young of placental mammals develop within the
uterus of the mother and are nourished by a direct blood supply.
Marsupial embryos,