THE MAMMALS 



237 



country. Of the other three the first (Monotremes) and 

 simplest of the eleven is represented by the duck-mole 



FIG. 131. Australian duck-mole (Ornithorhynchus paradoxus). One-fifth natural 



size. 



(Ornithorhynchus) living in the Australian rivers. Its 

 general appearance and mode of life are illustrated in 



