244 AUSTRALIAN AND TASMANIAN ANIMALS 



the males are furnished with a hollow spur, connected with a gland, on the hind- 

 leg, which appears to have poisonous properties. Although in stuffed specimens 

 the broad, depressed, and terminally expanded beak looks hard and horny, in life 

 it is covered with a soft and sensitive leathery skin, with a fringe, which appears 

 to be also sensitive, round its base. In all the older works on natural history, as 

 well as in most modern ones, the duckbill is represented as crawling or basking 

 either on the branch of a tree stretching over water from the bank or on the 

 bank itself. This is, however, utterly untrue to nature ; the creature never 

 voluntarily leaving the water except to enter its burrow by way of the submerged 

 entrance. Another universal pictorial error appears in connection with the fore- 

 feet, the five toes of which are connected by a web projecting considerably beyond 

 the tips of the claws. In pictures the animal is represented as standing when on 

 land with this web fully expanded, so that the claws do not touch the ground ; 

 but this is evidently an impossible pose, and it appears that when the animal 

 leaves the water the front edge of the membrane is folded backward beneath the 

 sole of the foot so as to leave the claws free. In the hind-feet the membrane is 

 smaller, reaching only to the base of the claws. The rather short tail is clothed 

 with coarse hair, but in old age frequently becomes bare on the under side. The 

 food, which in early life at any rate chiefly consists of snails, shrimps, and 

 aquatic insects, is conveyed after passing the edges of the beak into a pair of 

 capacious cheek-pouches, between which lies the short tongue. For the purpose 

 of masticating their food, young and half-grown duckbills are furnished in each jaw 

 with three pairs of cupped and cusped crushing teeth of an altogether peculiar and 

 unique type, although with a distant resemblance to those of certain small extinct 

 mammals from the Oolitic and Triassic formations of Europe. In appearance 

 these teeth may be compared to small square dishes, with two small knobs on one 

 side and a row of notches on the other ; with constant use these teeth, which are 

 very short-crowned, gradually become completely worn away, and are shed. 

 Their function is then discharged by broad horny plates attached to the roof of 

 the mouth and the edges of the lower jaw, these originally forming the beds on 

 which the teeth rested. In the upper jaw there is one pair of broad horny plates 

 behind and a smaller and narrower pair in front. 



The range of the duckbill is limited to Australia and Tasmania, and is 

 generally stated not to extend farther north on the mainland than 18° S. latitude. 

 Later investigations have shown, however, that in some parts of the country this 

 limit is considerably exceeded, duckbills having been obtained in Queensland so 

 far north as the Trinity Bay district, in latitude 16° 45' S. 



In addition to the normal use, the duckbill takes advantage of its capacious 

 beak as a means of carrying grass, leaves, and other materials for lining the 

 dwelling and nesting-chamber at the termination of the burrow, where the 

 accumulation is rolled up into a ball-like mass. When burrowing, the animal 

 chiefly makes use of the broad and flattened fore-paws. The burrow itself 

 consists of a chamber with two openings, one above and the other below the 

 surface of the water, the former being concealed amid the grass of the bank. 

 The passage to the globular terminal chamber may be as much as 16 yards in 

 length ; in the chamber itself, which is jointly occupied by the two sexes, are laid 



