202 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 
The fish is ambicolorate, but its appearance when 
seen from the blind side is rather bizarre (fig. 1, Pl. III). 
The greater part of this side is as perfectly pigmented as 
is the left, ocular side. But part of the head is perfectly 
white. ‘The skin covering the cheeks, the anterior and 
dorsal part of the head, the pre-operculum and _ inter- 
operculum, is colourless, but that covering the operculum 
and sub-operculum is_ perfectly pigmented. The 
coloration stops very exactly at the suture between 
operculum, sub-operculum, and inter-operculum. So 
much of the hook-like process as can be seen from the 
blind side is pigmented; so is the dorsal fin to its tip; 
and so is part of the skin covering the maxilla. The 
pre-maxilla and lower jaw are pigmented. 
The specimen rather resembles that described by 
J. 'T. Cunningham,* but the unique conditions of reversal 
in the latter specimen are absent. The fish I deseribe is 
normal so far as its symmetry is concerned. It is an 
immature female, normal in every respect except for the 
features noted above. Cunningham points out that the 
arrested migration of the eye, and the consequent 
abnormality of the dorsal fin, occurs frequently in 
ambicolorate specimens of the turbot and, less frequently, 
in ambicolorate specimens of other Pleuronectidae. The 
ambicoloration in the brill described certainly corresponds 
with the abnormality in question. But I have seen more 
specimens showing these characters—ambicoloration and 
arrested metamorphosis—among flounders than among 
any other Irish Sea flat fishes. 
* «A peculiarly abnormal specimen of the turbot.” Jowrn, Mar, 
Biol. Assn., Vol. VIII, No, 1, p. 44, Pl.3, 1907, 
