(1) The eggs are carried by the female in an open marsupium .(2) Their marsupium is well developed, opens to the rear, and contains only 2 teats.(3) A marsupium is present and opens to the rear.(4) Members of this family have a well developed marsupium that opens anteriorly.(5) In some (but by no means all) species of marsupials, females develop a pouch or marsupium in which the young are nursed.
