THE DUCKBILL OR PLATYPUS 



is folded downward beneath the claws, so as to leave the claws exposed. In 

 museum-specimens, however, the web is almost invariably shown fully expanded, 

 as in the accompanying illustration ; a condition in which it would obviously be 

 impossible for the animal to walk on land. 



The most remarkable external feature of the duckbill is undoubtedly the 

 duck-like, naked beak, pierced with two holes representing the nostrils. In 

 stuffed specimens, at any rate, this beak is dark-coloured and horny in consistence, 

 and looks as though it did not belong to the animal, but in life it is soft and tender 

 Medium-sized, dark eyes complete the physiognomy of this strange creature, in 

 which external ears are wanting. 



The internal arrangements of the mouth of the duckbill are scarcely less 

 curious than the exterior. In early life the mouth is furnished, both above and 

 below, with three pairs of somewhat quadrangular cheek-teeth, with raised and 

 cusped margins. Beneath these grow up certain large horny plates, and about the 

 time that full maturity is attained the teeth become worn out, and are finally shed, 

 thus leaving the horny plates as the sole masticating organs. 



This replacement of the teeth by horny plates appears to be connected with 

 the nature of the food, for while in early life the duckbill appears to subsist mainly 

 on water insects and other comparatively soft aquatic creatures, later on it takes 

 to feeding almost entirely on bivalve shells of one particular species ; and for 

 crushing the stout shells of these molluscs it has been suggested that the tough 

 horny plates are better suited than brittle teeth. 



Duckbills, except when in their burrows, pass the greater portion of their 

 time in the water, selecting quiet pools for their favourite haunts. In such 

 situations they may be seen on a still evening floating and diving, and looking more 

 like bottles in the water than anything else. They obtain their food chiefly by 

 probing in the mud with their duck-like beaks. The dwelling-chamber of the 

 burrow is situated in the bank above the water level, but its entrance is below 

 the surface, although there is also an exit on the land. In the pairing-season 

 the males, which are armed with a poison-bearing spine on the inside of each 

 hind-leg, fight fiercely among themselves. 



The duckbill, of which there is but a single species, is absolutely confined to 

 southern and eastern Australia and Tasmania ; and its nearest living relative is 

 the echidna, of which a picture and notice follow. 



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