BY T. HARVEY JOHNSTON. 127 



numbers at Lammermoor Station, on a tributary of the 

 Barcoo. This fish he believed to be identical with the 

 golden perch of the Murray River, Plectroplites ambiguus. 

 A thunderstorm brought down a freshet heavily charged 

 with silt and the fish mortality apparently ceased. The 

 cause was believed to be Saprolegnia, or some related fungus. 



Mr. C. E. Lord, Hobart, wrote stating that Saprolegnia 

 was well known in Tasmania, where it attacked fish, 

 particularly in dry seasons, and although the fungus could 

 be controlled in the hatcheries by immersing diseased fish 

 in a salt water bath, no method of treating the affected 

 lakes and rivers of the island had been discovered. 



As far as I have been able to ascertain. Saprolegnia 

 has not been as yet recorded as occurring in Queensland. 

 Bailey* does not mention it in his census of our plants, 

 nor do either McAlpinef or Cookef make any reference to 

 its presence in any of the Australian States. In L888, 

 however, Mr. J. D. Ogilby** reported that black bream 

 Chrysophrys australis ( = Sparus australis) and eels, Anguilla 

 australis were taken in the freshwater portion of the Port 

 Hacking River, N.S.W., dying from disease caused by 

 Saprolegnia sp. A concise description of the appearance 

 of affected fish was given. He believed that the prevalence 

 of the parasite was due to the long continued drought and 

 to the almost complete stagnation of the fresh water. Dr. 

 J. C. Cox in commenting on Mr. Ogilby's remarks, pointed 

 out that the epidemic was due to the unhealthy and 

 unnatural conditions under which the drought had com- 

 pelled these particular fish to live. In 1902 Dr. Greig 

 Smith? exhibited before the Linnean Society of N.S.W., a 

 salmon affected with Saprolegnia ferax, which was forwarded 

 to him from Tasmania. 



The specimen submitted to me presented the typical 

 appearance of a Saprolegnia infested fish. There were 



* F. M. B liley. Comprehensive Catalogue of Queensland Plants, 

 1912, Govt. Printer, Brisbane. 



t D. McAl])ine. Gystematic Arrangement of Australian Fungi, 1895. 



JN. C. Cooke. Handbook of Australian Fungi, 1892. 



** J. D. Ogilby. Note on the cause of death in fishes from the National 

 Park, N.S.W. P.L.S., N.S.W., 3 (n.s.), 1888, pp. 890-1. 



§ Greig Smith. Notes and Exhibits P.L.S. N.S.W., 27, 1902, p. 

 495. 



