HABITS OF CERATODUS 
in order to ascertain the facts. It is only in Queens- 
land that Cevatodus is met with. In the Mary and 
Burnett rivers it occurs in deep quiet pools, which are 
full of water in wet and dry seasons alike. Some per- 
sons, impressed doubtless with the real likeness which 
this “fish”? bears to the amphibia, have asserted that 
it basks in a crocodile-like fashion upon logs. The 
Ceratodus, however, cannot leave its native streams ; 
and instead of showing the least trace of an amphibious 
way of life, it dies with peculiar ease when removed 
from the water. It is probable, thinks Professor Bald- 
win Spencer, that a large water lizard, common in and 
along the banks of the same rivers, is responsible for 
the stories of the Cevatodus basking upon tree trunks. 
With the laudable view of preserving so far as possible 
this interesting survival from a bygone age, steps have 
been taken in Australia to transfer this fish to other 
rivers, where it apparently does well. Our descendants 
may find that if these experiments continue to be suc- 
cessful, the Cevatodus may lose some of its peculiarities. 
At present the rivers in which it swims are not quite 
ideal as fish reservoirs. During the hot weather ill 
weeds grow apace, and also decay : there results a foul- 
ing of the water and a concomitant lack of pure air, 
and an increased difficulty for the Barramundi to 
breathe. Nature, however, though a strict economist, 
invariably permits, or rather insists upon, the wind 
being tempered to the shorn lamb. The dyspnceic 
Ceratodus has, in consequence of these difficulties, 
acquired a swim bladder which performs the offices 
of a lung, instead of being merely, as in other fish, a 
hydrostatic apparatus. The lung has its own special 
artery and vein exactly as in other creatures with lungs, 
and the fish comes to the top of the water to inhale air, 
just as any land-frequenting but occasionally aquatic 
and diving animal does. In addition to this, it has the 
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