348 THE FLOUNDER FAMILY. 



dorsally and ventrally, and in the progress of the right eye 

 towards the left. The marked notch behind the angle of the 

 mandible, and the elevation of the head behind the right eye, 

 are also noteworthy features. When the right eye mounts the 

 dorsum, the dorsal fin forms a high arch behind it. The body, 

 moreover, has considerably increased in depth in comparison 

 with its length, a specimen about 9 mm. in total length having 

 a depth of 6 mm. Besides the "touches" of pigment on the 

 fins, a few minute black points are scattered over the left 

 surface- — the right being covered with minute dots almost as 

 densely as before. In Holt's examples from the Irish Sea, a 

 reduction of pigment took place from about 7"25 mm., just 

 before the arrangement in " touches " occurred. Holt in his 

 oldest stages counted from 70 to 80 rays in the dorsal, and 

 from 60 to 65 rays in the anal fin. He carefully discusses 

 the question to which species of topknot his examples most 

 probably belong, and concludes that it is Bloch's topknot 

 (Rhombus unimaculatus). In regard to the form described in 

 the preceding pages, however, the post-larval stages probably 

 belong to MuUer's topknot, the most common species ; indeed 

 Bloch's topknot is unknown in the neighbourhood, though the 

 Norwegian topknot is occasionally found. 



Dr Petersen mentions a specimen of 13 mm. captured by 

 Prof Sars in August, in which the characters were nearly those 

 of the adult, except that the pectorals had only traces of true 

 rays. " The distribution of the colours is peculiar, the left side 

 being dotted with round dark spots of about the same size, 

 evenly distributed over the whole fish, head, body and fins, and 

 amongst these spots are pointed, soft warts like those which are 

 found in somewhat older animals\" 



Of the subsequent stages of Miiller's topknot, a specimen of 

 41'5 mm. was tossed on shore after a storm on January 16, 1895 

 (Plate XIV, fig. 9). The greatest diameter (across fins) was 

 24'5 mm. The left side is dappled with distinct black spots — 

 one of which runs obliquely from each eye. They are inde- 

 pendent of the dark touches which mark the dorsal and anal 

 fins. A series of small pale specks are also dotted over the 



1 Op. cit. p. 135. 



