22 The Salmon 



smolt was wanted, the box was raised and the water ran through the 

 holes. One man caught the smolts and handed them to the one who 

 held them in position whilst they were being marked. They were 

 instantly dropped into the river again, and swam away at once. 

 The greatest care was taken to mark nothing but smolts of Salmo 

 sa/ar, all parr and yellow fins being rejected; so that so far as we could 

 judge nothing but smolts were marked. I intended all the smolts to 

 be marked in the same place in the gristly part in front of the dorsal 

 fin ; but after a time the markers began to take in two rays of the 



FIG. 19. Marked Grilse, 3^ Ibs., 3rd July 1906. Smolt marked May 1905. 



fin without my observing it. On discovering this, I decided to do 

 the marking again another year, as I was afraid the aperture would 

 grow upwards with the fin and the wire would fall out, thus making 

 our work go for nothing. We watched carefully during the whole 

 of the summer, but no marked fish were found. On the ist of June of 

 the following year we got the first wire in a grilse which weighed 

 2 Ibs. 15 oz. The mark and the fish are shown in Fig. 14. 

 The mark was slightly spoiled with the net. This grilse with 

 the mark on it (Fig. 14) we handed over to the Perthshire 

 Society of Natural Science. The capture of this grilse was the 

 means of making our manager, Mr. David Robb, our Secretary, 

 Mr. Harry Robb, Mr. W. M'Nicol, and Mr. John Robertson 



