AN AMBICOLORED TURBOT 147 



way between the lateral line and the anal fin. The under 

 side is of the same colour as the upper, but the dark portion, 

 which spreads as a continuous patch over the greater part of 

 the surface, is bordered by paler bands running close to the 

 bases of the dorsal and anal fins, and coming to an end 3 

 and 6 cms. respectively from their hinder terminations. 

 The posterior margin of the operculum also is distinguished 

 by a paler border stretching for a short distance above and 

 below the right pectoral fin ; and that fin itself, as in a 

 specimen described by Messrs. Cunningham and MacMunn, 1 

 has on its outer surface a narrow edging of white 5 mm. in 

 breadth. The inner surface, that turned towards the body, 

 is without pigment. Except for the pectoral fin no portion 

 of the fish is colourless, but we cannot affirm that the colour 

 on both sides is symmetrically distributed, unless, indeed, 

 the paler shades whose distribution has been noted above 

 are due to post-mortem changes. On both upper and under 

 surfaces dermal denticles are scattered with similar frequency, 

 but those on the under surface are much worn an evidence 

 that the fish had long adopted the mode of swimming 

 common to its kind. 



Only a slight notch separates the anterior portion of the 

 dorsal fin from the head, the free ray-bearing portion 

 measuring but i I mm. The dorsal eye, instead of lying on 

 the top of the head, has crossed over the ridge, its position 

 approaching that assumed in a normal specimen. The 

 interorbital distance, however, is greater than usual, for, 

 taking as a standard the transverse diameter of an eye, the 

 eyes are almost two diameters apart, while the normal space, 

 according to Day, 2 is only one diameter. Further, the 

 upper eye lies, not in line with the notch, but opposite the 

 attached portion of the fin, which is adnate for 6 mm. in 

 advance of the anterior border of the eye (see Fig.). 



Of those cases of which I have been able to see descrip- 

 tions, this resembles most closely that of a Brill recorded by 

 Cunningham and MacMunn 3 from notes supplied them by 



1 Cunningham, J. T., and MacMunn, C. A., "On the Coloration of the 

 Skins of Fishes" ; Phil. Trans. 1893 (London, 1894), p. 803. 



2 Day, F. , "Fishes of Great Britain and Ireland,'' vol. ii. p. 12. 



3 Cunningham and MacMunn, I.e., p. 80. 



