MONOTKEMATA. 



473 



grinders, but 1 have no roots, The eyes are small but brilliant, and 

 the orifice of the ear is readily detected by its opening and closing 

 in a living animal, though scarcely perceptible after death. This 



r- f f /> 



FlO. 398. THE DUCK I5ILL. 



creature is sometimes called the Water-mole. It delights to haunt 

 the broad and tranquil ponds that are formed by the expansion of a 

 stream, in which it swims and dives with great facility. Its 

 burrow is formed in the bank, and runs to a great distance under- 

 ground, sometimes extending even fifty feet. A nest of grass and 



-eg- 



FlG. 399. BUKltOVV OK OttMTHORYNCHUS. 



weeds is formed at the extremity, where the parent rears it young. 

 The Ornythorynchus inhabits Australia. 



The Porcupine Ant-eater (Echidna aculeata] is another Austra- 

 lian animal, the muzzle of which forms a beak, but less developed 

 than in the Duck-bill. It is clothed with bristly black hair, among 



