322 
Proceedings of Royal Society of Edinburgh. [sess. 
Tweed ( Tweed Salmon Reports , 1868). The marking was done in 
1854, 1855, and 1857, and in each case the recapture of the fish 
as a grilse was fully a year after the date of marking. 
In the spring of 1904 I commenced experiments in smolt- 
marking at the Cunninghaugh Ponds, near Fochabers, the property 
of the Duke of Richmond and Gordon. The method first used 
was the attachment of a small silver disc to the operculum by 
means of a split pin passed through the operculum from beneath ; 
but so many of the marks were torn out, by the yielding of the 
delicate bones of the gill cover, within a few weeks, that the 
method was abandoned. I next used, on the Tay, a simple piece 
of silver wire, which I passed through the skin of the back close 
to the adipose fin, and formed into a loop by twisting the ends 
together. The method seemed fairly satisfactory, but the wire 
used was rather heavy, and interfered somewhat with the balance 
of the little fishes as they swam away. Next year (1905) the 
Tay Salmon Fisheries Company, under Mr P. D. Malloch’s super- 
vision, took up the marking of smolts, and a wire was employed of 
lighter weight — so thin that it could be easily cut with scissors. 
The wire was passed through the dorsal fin close to the anterior 
border and a short distance above the base of the fin rays, and was 
formed into a loop or loose ring and the ends snipped off. Mr 
M‘Nicol had charge of the operations, and succeeded in marking 
6500 smolts in the spring of 1905. No recaptures were made 
in 1905. 
This summer (1906) a considerable number of those smolts 
have been recaptured as grilse. In each case the recapture has 
been made in the Tay estuary, wdiere the marking was originally 
conducted. The particulars of the first five are as follow : — 
1st June 1906, grilse weighing 
26th 
28th „ 
3rd July ,, 
5 5 
4th 
5 J 
2 lb. 15 oz. 
4 „ 8 „ 
4 „ 12 „ 
3 „ 4 „ 
5 8 „ 
The specimen exhibited is the second on the list, caught on 26th 
June, and weighing 4 lb. 8 oz. It is a male fish with rudimentary 
testes, and measures to the fork of the caudal fin 24 inches 
