174 block's TOl'KNOT. 



there is some reason to suppose also that Bloch's Topknot 

 sometimes inhabits deeper water, as it has been taken from 

 the stomach of a Ling which was caught at a depth of more 

 than thirty fathoms. Mr. Thompson, of Weymouth, has informed 

 me of an example that was ornamented on the lateral line, 

 near the tail, with a black spot, which had an orange-coloured 

 spot in its centre; and it was also marked with several puce- 

 coloured spots along the base of the dorsal and anal fins. 



In regard to the relative dimensions of this species Dr. 

 Gunther says that the height of the body is nearly one half 

 of the total length without the caudal, and the length of the 

 head two parts out of seven; but in these proportions there 

 appears to be an occasional variety, unless we are to suppose 

 that a third species occurs on our coast. Mr. Thompson, of 

 Belfast, obtained a specimen which, with a length of six 

 inches and a half, was only two inches and seven lines in 

 breadth, and 1 possess the note of an example which was 

 brought to me that was six inches long, and two inches and 

 a fourth in width. Another also, which was mutilated when I 

 saw it, appeared to be of a length greater than the generality 

 of these fishes. It seemed much flatter in form, the colour 

 not dark, and the possessor, who had removed the lower 

 surface before I saw it, assured me that the dorsal and anal 

 fins ended in a line with the tail, without passing to the 

 lower surface. The number of the fin rays was, — dorsal 

 eighty-eight, anal sixty-eight, ventral six, pectoral ten, the 

 caudal fifteen. It remains yet to be seen whether either of 

 these was the Rhombus cardina of naturalists. 



