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this must be one of their natural foods ; the salt-water fish 

 was skinned, cut into slender pieces, kept very fresh, and free 

 from contact with salt. This they also took and consumed 

 in large quantity for many hours during the day ; to a less 

 extent at night. Being nocturnal animals this was strange, 

 but they doubtless were not satisfied with the food provided, 

 hence the necessity of their coming out during the clay. For 

 the most part their food is taken under water ; they turn 

 over the sand and small stones at the bottom with their 

 powerful bills, and collect in this manner in their cheek 

 pouches whatever they discover, then they rise to the 

 surface, and triturate their food before swallowing it ; this 

 trituration is indicated by a slight lateral movement of the 

 jaws. I have also seen them take pieces of fish or worms off 

 stones out of water ; after doing so they always return to the 

 water before swallowing it. It may be mentioned these 

 cheek pouches on either side of the jaw are excellently 

 adapted for the primary reception of the food, for organised 

 as the animal is to swallow fluids, it could not well triturate 

 the food at the bottom of rivers, vi^hich is done therefore on 

 its reaching the surface of the water. These creatures 

 remain under water a minute or more, which depends upon 

 the supply of food, rising rapidly to the surface if it is 

 plentiful. When on the surface of the water, and food has 

 been abundant, several minutes elapse before the food is 

 triturated and in a condition to swallow. There is a popular 

 idea that their food is always taken with sand, which is 

 necessary for digestion, but with the exception of a little 

 taken whilst procuring their food, this is not true. What is 

 taken for sand is the tinely triturated epidermis of beetles, 

 shrimps, etc., which is swallowed, and appears to exert a 

 special and necessary action over digestion and absorption. 

 My not j^roviding these insects doubtless led to the death of 

 my specimens. This material may act as the stones in the 

 gizzards of birds, to still further prepare food for absorp- 

 tion. When swimming the forepaws are widely expanded, 

 being convex forwards, propelling themselves by an antero 

 lateral movement. The hind paws and tail take but little 

 share ; the former have a slight lateral horizontal movement, 

 the tail lazily moving with body. When diving the head 

 is rapidly thrown beneath the body, front paws quickly 

 moving until the bottom is arrived at, when they are seen 

 turning rapidly over with their bills the sand, and even large 

 stones, the tail turning from side to side as a rudder, being 

 at an angle of 25 degrees from the river's bed. A train of 

 small bubbles proceeding from the nose marks the exact 

 course the animal is taking. The tail is the first part to 

 reach the surface of the water. I do not know whether this 



