PARR AND SMOLTS 95 



insert here a plate indicating in colour the general appearance and 

 markings of (i) a trout, (2) a Loch Leven trout, (3) a sea-trout, and (4) a 

 salmon, when at the " two year old " stage of growth (Plate V). 



Young salmon and trout are both freely speckled with dark and 

 crimson spots, and as to these something may be said. The dark spots 

 of the salmon parr are small and occur only above the lateral line, 

 while those of the young trout are generally bolder and are often 

 numerous below the lateral line as well as on the back and shoulders. 

 Each spot of the trout, too, as I have noted elsewhere, is usually 

 surrounded by a ring or halo paler in hue than the general body colour. 

 But a very distinctive feature of the salmon parr which one clearly 

 recognises when attention is drawn to it is the intense black of the spots, 

 generally one, two or three in number, on the operculum, that is, on the 

 cheek. It may be noted too that the dorsal fin of the salmon parr is 

 never very boldly spotted, while that of the trout almost invariably is. 



Dealing with the colouring of the fins, never a very certain feature, 

 it may be stated that the pectoral fins of the salmon parr appear of a 

 watery paleness compared with the rich yellowish-brown of those of the 

 trout. So too the adipose fin of the young trout has nearly always, but 

 I think not always, a reddish fringe, that of the salmon parr being in 

 colour merely a dark continuation of the dark blue back. 



Again viewing both fish broadly, but now in regard to shape, it will 

 be seen that the salmon parr has a more graceful outline and a general 

 air of greater delicacy than the young trout. Coming to details, its 

 head is neater and its mouth relatively smaller than that of the trout, 

 for, while the jaw of the salmon parr reaches back to a level with the 

 middle of the eye, that of the trout extends as far as, or even beyond, 

 the posterior margin of the fish's eyeball. The eye of the salmon parr 

 is also relatively larger than that of the trout, and, as already noted, is 

 set more nearly in the middle line of the head when viewed in profile, 

 that of the trout being set rather above the middle line. 



