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hindmost pari of the operculum, 3 — 6 spines on the under side of the lower jaw, and 

 two large groups "f spines at the upper cud of the elavicuhc (M'Tntosh's otocytic 

 spines*). 



Of all these spines with which the turbot is thus accoutred, particularly on 

 the left side of its head, there arc but slight suggestions in the In-ill*); certainly, 

 there are little spines at several of the same places where we find them in the 

 turbot, hut, partly, they are so smal that they scarcely protrude from the skin, 

 partly the angular crest over the eye is quite missing as such, though a very incon- 

 siderable row of spines may replace it. 



The whole spiny equipment is subject to some variation in both species; but 

 the projecting crest over the left eye is so distinct that it may easily be seen with 

 a weak magnifying lens, and it is always characteristic of the turbot; — it is to 

 he found also over the right eye. 



In a turbot of 21""" (plate I, fig. 2), which had true rays in all its fins, and 

 evidently also the full or nearly the full number of rays, 62 in the dorsal lin ami 

 c. 47 in the anal fin, and which by its round form and short snout**) clearly 

 proved to be a turbot in transition between the pelagic stage and the bottom 

 stage, there were still traces left of the strong crest over the left eye, spines on the 

 shoulder ami a few scattered ones on the operculum, but the whole spiny equip- 

 ment as well as the crest was now fast disappearing. — The right eye was just 

 situated on the frontal edge. — The right side of the fish had still traces left of 

 the spines, but the pigmenting was very slight. — 



1 have not got any brill at a stage exactly corresponding to this in size, but 

 in a young one, c. 20 nnB long (plate I, tig. fi) whose right side was only slightly 

 pigmented, and whose right eye is situated on the frontal edge, the spiny equip- 

 ment is quite disappeared with the exception of a few spines at the hind-edge of 

 the operculum. This young brill hail still embryonic fin rays in the pectorals. 



The pectoral gets its true rays last of all the tins; when they have appeared 

 the pelagic stage is at an end, and the tish goes to live on the bottom. Before I 

 mention the bottom stage, however, I must make some observations on the pelagic 

 young ones, which are smaller than the above-mentioned c. 1 •">""" long young tur- 

 bots and brills. 



Already with a length of 7 — 8""", the smallest young ones 1 have collected 

 plate I, tig, 4 & 8), the turbot has got the peculiar spiny equipment of its head> 

 while I have seen no such thing in brills of the same length. On the frontal-edge 

 of the brill, on the other hand, a peculiar soft hump appears, just before the 

 foremost rays of the dorsal tin; it disappears later on during the wandering of the 

 eye, and it seems as if the turbots never get anything quite corresponding to this. 



s ) See :ils.. 8cM0dte's picture of it. 



*) This is on the whole, an excellent mark to distinguish also between larger turbot? 

 and brills. — In young ones under Sunn, this difference is not so conspicuous. 



