520 T. H. JOHNSTON AND M. J. BANCROFT, 
SOME NEW SPOROZOON PARASITES OF QUEENS- 
LAND FRESHWATER FISH. 
By Prof. T. HARVEY JOHNSTON, M.A., D.Sc, etc., and M. J. 
BANCROFT, B.Sc. 
With Plates XLIII- XLVII. 
[Read before the Royal Society of N. S. Wales, December 4, 1918. | 
THE material for this paper was collected during an investi- 
gation of the recent epidemic amongst freshwater fish in 
Central Queensland. We are indebted to several of the 
officers of the Longreach Shire Council for some of the 
specimens obtained. All the fish examined were taken in 
the Thomson River at Longreach, with the exception of 
one, Scicena australis, which was captured in the Brisbane 
River in the vicinity of Ipswich. All the specimens have 
been kindly identified for us by Mr. J. Douglas Ogilby of 
the Queensland Museum. We have used the classification 
given by Auerbach (‘‘Die Cnidosporidien eine monograp- 
hische Studie,’’ Leipzig, 1910). 
MYXOSPORIDIA. 
Family MYXIDIIDA. 
MYXIDIUM THERAPON D. sp. 
Migs, 15 97 12: 
Hosts:—Therapon carbo Ogilby and McCulloch; and 
Therapon hilliit Castelnau. 
This parasite was found infesting the gall bladder of both 
these Therapons. Only one specimen of T. carbo was 
secured. Of thirteen examples of T. hillii, the common 
‘‘black bream”’ or “‘ grunter’’ of the Thomson River, nine 
were infected. It apparently has no harmful effect upon 
its host. When the gall bladder of a parasitised individual 
