48 Aquatic Lite 
The Bitterling 
About friend Bitterling. 
this fish, as you know, is readily deter- 
mined during the breeding season, when 
the female protrudes her oviduct and the 
male changes to gorgeous colors. I have 
come to the conclusion that the sexes can 
be distinguished at all times. You will 
notice that some individuals have a cer- 
The sex of 
interesting species. The bitterling is not 
a new fish to American aquarians, though 
it is now extinct in our collections. Other 
than in sex discrimination, the species 
presents another suggestion for observa- 
tion. ‘The eggs are deposited by the fe- 
male in the syphon of a mussel. Here 
incubation takes place and the fry leave 
the foster mother ten to fifteen days after 
EVEN NNN VENI NEN NEN NEN NESE NNN ENN NNN NNN NEN 
Rhodeus amarus (Bitterling ) 
RRS ASG NS ASA SASS AS SE 
Photograph by Dr. E. Bade 
SS SS Ss 
BUNNIES NENG ENENEN NEN Se NEN NNN NENG NNN 
tain amount of red in the eye, whilst in 
others it is entirely absent. I believe, as 
a result of my personal observations, that 
it is the males which possess the “red 
eye.” I shall be glad to know if this is 
so, or 1f you will personally attempt to 
confirm my opinion.—John R. Shattock, 
in a letter to the editor. 
The activities of the submarines (de- 
spite Mr. Shattock’s efforts as a member 
of the British Royal Flying Corps) made 
it advisable to postpone a shipment of this 
the insertion of the eggs. It will be inter- 
esting to determine if the fish will accept 
an American mollusc, and if the mussel 
will concur in the interrelationship. If 
the bitterling has been bred here, using 
an American species, the fact has appar- 
ently not been published.—E ditor. 
meee 
When arranging the plants in an 
aquarium, leave the centre clear. The 
light will be better diffused and the 
fishes more readily observed. 
