THE DUCK-BILLS. 237 
mentioned. Although the usual number of eggs is two, it ap- 
pears that there may be occasionally either three or four. After 
the period of suckling ceases, the young are said to be fed by 
the parent on insects and comminuted shell-fish, until suffi- 
ciently strong and active to shift for themselves. 
Describing the capture of a pair of well-advanced young in 
the nest, Dr. Bennett states that when first seen, although 
there was plenty of growling, “there was no movement on the 
part of the animals to escape. On being taken out, they were 
found to be full-furred young ones, coiled up asleep, and they 
growled exceedingly at being exposed to the light of day. 
There were two of them, a male and female, of the dimensions 
of ten inches from the extremity of the beak to that of the tail. 
They had a most beautiful, sleek, and delicate appearance, and 
seemed never to have left the burrow. The nest, if it may be 
so termed, consisted of dry river-weeds, the epidermis of reeds, 
and small dry fibrous roots, strewed over the floor of the 
cavity, which was of sufficient size to contain the mother and 
her young.” 
As we have said, the food of the Duck-bill consists of 
various small water-animals, such as crustaceans, insects and 
their larvee, snails and worms, which are dug out of the soft 
mud by the tender muzzle, and are taken into the mouth 
accompanied by a considerable quantity of sand, which results 
in the rapid wearing away of the molar teeth of the young 
animal. Sleeping for the greater portion of the day comfort- 
ably rolled up in their burrows, the Duck-bills are mainly noc- 
turnal in their habits, not generally issuing forth to feed till the 
shades of evening proclaim the approach of night, although at 
times they may be seen abroad in full daylight. Except for 
the loud growling uttered when they are dug out of their 
burrows, it appears that they are for the most part silent 
creatures. 
