﻿THE DUCK-BILLS. 235 



they may be readily recognised by their dark bodies just seen 

 level with the surface, above which the head is slightly raised, 

 and by the circles made in the water around them by their 

 paddling action. On seeing them, the spectator must remain 

 perfectly stationary, as the slightest noise or movement will 

 cause the timid creature instantly to disappear, so acute are 

 they in sight or hearing, or perhaps in both ; and they seldom 

 reappear when once frightened. By remaining perfectly quiet, 

 however, when the animal is paddling about, it is possible to 

 obtain an excellent view of its movements in the water; it 

 seldom remains longer than for one or two minutes playing on 

 the surface, but dives, and reappears a short distance above or 

 below the place at which it was observed to descend." 



Later on. Dr. Bennett observes that " these creatures are 

 seen in the Australian rivers at all seasons of the year, but are 

 most abundant during the spring and summer months. . . . 

 The best time for seeing them is early in the morning or late 

 in the evening. During floods and freshets they are frequently 

 perceived travelling up and down the rivers; when going down, 

 they appear to allow themselves to be carried by the force of 

 the stream, without making any exertion ; but in swimming 

 against the current their muscular pov/er is exerted to the ut- 

 most to stem its force, and generally with success. I recollect, 

 however, seeing two make repeated and ineffectual attempts to 

 pass a small waterfall in a rapid part of the river, and, after 

 many persevering efforts, they were unable to attain their 

 object." 



In describing the structure of the burrow, the sanie aathor 

 states that on a certain occasion on arriving at the spot where 

 one had been partially opened by the natives, he found it 

 situated in a steep bank adjacent to the river, upon which 

 grass and other herbaceous pL nts grew in abundance. The 

 native guide, by whom he was accompanied, "putting aside 



