92 IJFE-HISTORY OF CERATODUS (NEOCERATODUS) FORSTERI, 



Very few, however, sur\ived, and the last one died when 

 two years of age. Compared with the growth that obtains 

 in most fishes, that of Ceraiodus is very slow ; at birth, the 

 fish is about half an inch in length and in two years it had 

 hardly reached the length of five inches. 



Not being satisfied with the results obtained, I removed 

 the trough and set it up near m}- house in Eidsvold. For 

 two seasons I introduced over fifty young Ceratodus, several 

 weeks old, only to see them all disappear within a couple 

 of months, possibly having been devoured by dragon fly 

 larvae, of which there was abundance. Endeavours are 

 again being made, this time in the direction of excluding 

 water-beetles, dragon-fly larvae, frogs, and other animals^ 

 some or all of which attack the little fish. 



An}' one having read the descriptions of Ceratodus as 

 given in books would have learnt some erroneous ideas of 

 the fishes habits, amongst others, in the matter of the 

 frequencj- of coming to the surface of the water to take in 

 air. For instance, Dr. Bashford Green, from observations 

 made on two Ceratodus in captivity at the Zoological 

 Gardens, London,* writes : — '' At intervals of 40 to 60 

 minutes the fish shows uneasiness in the water, gasps- 

 several times, then rises to the surface, exhales and draws 

 in a mouthful of air somewhat spasmodically ; " then 

 again, Richard 8emon, in his book '" In the Australian 

 Bush "' p. 92, states : — ■" I kept Ceratodus alive in great 

 barrels and self-dug water holes ; I saw them appear at the 

 surface e\'ery thirty or forty minutes, etc."' At Eidsvold 

 I kept two large Ceratodus alive in a tank with water- weeds 

 under favourable conditions for two years, and during that 

 time I never once was fortunate enough to see one rise to 

 the surface to breathe ; one might remain quietly a whole 

 afternoon at a lagoon on the Burnett River, in which lagoon 

 there were numerous large Ceratodus, and never once see 

 or hear a fish rise ; at other times he might see several 

 rises in that time ; were the statements, as made in books, 

 true one would expect to see hundreds of rises. 



With regard to Semon's observations I can onl}' con- 

 clude that his fish were sick or dying. The fish at the 



* " The Animals of Australia," Lucas and Le Souef, p. 300. 



