X 
THE COLOURS OF FISHES 
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with spots and stripes of brilliant blue, while the 
female, often classed as a separate species under the 
name of 0. aurita , is of a pale yellow or flesh-colour, 
with brown markings; a so-called hermaphrodite 
specimen was obtained by Mr. Saville Kent in 
which the two sides displayed respectively the two 
types of coloration. One of the parrot - fishes 
also, Pseudoscarus rivulatus, displays marked sexual 
coloration, the female being blue and yellow and the 
male green and red, the prevailing tints during life 
being respectively blue and green—an interesting 
case because it recalls the conditions seen in some 
parrots. In connection with the coloration of the 
parrot-fishes there has been noticed a case of so- 
called “ mimetic ” resemblance in the case of a goby 
('Gobius douglasi ), which is green banded with red, 
the usual colours of the parrot-fish. The giant 
anemones already mentioned have frequently small 
commensal fishes living in their central cavities ; thus 
Discosoma kenti is inhabited by Amphiprion percula , 
a small red fish with broad white bands, the bands 
being separated from the red ground colour by a 
black margin ; Discosoma haddoni , on the other 
hand, is inhabited by Amphiprion bicinctus , which is 
closely similar in colouring but is without the black 
margins to the white bands. Both sea-anemones 
show great colour variation, but in all cases their 
colours are sharply contrasted with those of their 
commensals. 
It is interesting to note that the brilliancy of tint 
is entirely confined to the fishes which actually live 
among the brightly coloured corals. Those living 
in the lagoons which are floored with coral sand and 
