298 APPENDIX. 



He marked many small grilse after they had spawned in 

 winter and were about to re-descend into the sea. He had re- 

 captured them in the course of the ensuing summer as finely 

 formed salmon, ranging in weight from nine to fourteen 

 pounds, the difference still depending on the length of their 

 sojourn in the sea. He has tried these experiments for many 

 seasons, but never twice with the same mark. A specimen 

 marked as a grilse of four pounds in January, 1842, and re- 

 captured as a salmon of nine pounds in July, was exhibited 

 to the Society ; it bore a peculiarly twisted piece of copper 

 wire in the upper lobe of the caudal fin. Those marked and 

 retaken in 1841 were marked with brass wire in the dorsal 

 fin. With these and other precautions, Mr. Young debarred 

 the possibility of any mistake as to the lapse of time. Both 

 grilse and salmon return uniformly to their native streams ; 

 at least it very rarely happens that a fish bearing a particular 

 mark is found except in a river where it was so marked. 

 Salmon in the perfect state, as to form and aspect, also increase 

 rapidly in their dimensions on again reaching the sea. A 

 spawned salmon weighing twelve pounds was marked on the 

 4th of March, and was recaptured on its return from the sea 

 on the 10th of July, weighing eighteen pounds. 



Mr. Young is of opinion that salmon rather diminish than 

 increase during their sojourn in rivers, and he illustrates this 

 and other points of his subject by numerous experiments and 

 observations. 



THE END. 



Printed by A. Spottiswoodb, 

 New-Street-Square. 



