RELICS OF PRIMITIVE TYPES
There live in Australia and New Guinea two curious little animals that most nearly represent in their low and generalized organization the primitive mammals, and differ so essentially from all other mammals that they are classed by themselves as Prototheria ("first beasts"). They are the duckbill (Ornithorhynchus) and the spiny anteater (Echidna). The duckbill is a small, softly furred, web-footed creature, as aquatic in its habits as a beaver, which finds its food in the worms and other things that live in and on the mud of its chosen stream, and digs a burrow in the bank for its home, where it stays most of the daylight hours, and where its young are born. Its special peculiarity is that instead of the muzzle and mouth of an ordinary mammal, it is furnished with a bill like that of a duck, and each jaw is armed with horny plates to do the work of teeth; in the young ones true molar "milk" teeth are present, but are soon shed. The cheeks contain pouches in which a quantity of food can be stored, the animal carrying it in to the safety of its burrow to be eaten, and so avoiding the danger of being out for a long time of feeding.
| Photo, American Museum of Natural History |
| OPOSSUM MOTHER AND YOUNG |
The echidnas are equally small, about eighteen inches long, covered with a mingled coat of hair and strong spines, and mounted on short legs and feet armed with powerful claws, for this animal dwells on land, and not only burrows, but must tear to pieces the hills of the ants that form its only food. Its round little head terminates in a long, slender snout containing a ribbon-shaped tongue with which it licks up the ants from their ruined nests.
| ANTEATER, WHICH LIVES ON INSECTS CAUGHT IN THE STICKY SALIVA OF ITS LONG TONGUE |