and on the Ova of the Salmon, 109 



arrived behind the sluices of the salmon-cruive, and while they 

 yet remained in the water, the indistinct transverse markings of 

 the parr were still to be seen, especially when they happened to 

 be swimming in a particular light, and occasionally as their po- 

 sitions happened to change, the bars became again imperceptible. 

 I also examined a number of them in the hand, and by holding 

 them at a particular angle to the eye, the bar could be distinct- 

 ly perceived, but if the fish was viewed with the broad side pre- 

 sented directly to the eye, this peculiar appearance could not be 

 recognised. Should all those methods fail, in shewing the cha- 

 racteristic bars of the parr on the salmon fry, it is only neces- 

 sary to remove the scales from the sides, and the bars will be 

 distinctly visible on the skin beneath. The next opportunity 

 which I had of witnessing the salmon-fry in their progress to- 

 wards the sea, was on the 3d May 1833. These had in every 

 respect the same appearance as those I have already described. 

 They passed down the river in families or shoals, of from forty 

 to sixty and upwards, their rate of progress being about two 

 miles an hour. The caution which they observed in descend- 

 ing the several rapids they met with in their journey was very 

 amusing. They had no sooner come widiin the influence of 

 the rapid current than they in an instant turned their head up 

 the stream, and would again and again permit themselves to be 

 carried to the very brink of the fall, and as often retreat, till at 

 length one or two bolder than the others permitted themselves 

 to be carried over by the current, when the whole, one by one, 

 disappeared, and as soon as they had reached comparatively 

 slill water, they again turned their heads towards the sea and 

 resumed their journey. 



Qd, The third and last opportunity I had of witnessing them 

 migrating, was in May last (1836), when, as I have stated, 

 I compared a few of them with those which had assumed the 

 silvery dress of the salmon fry, after being in my possession 

 two years, in the character of the parr. The river, during this 

 month, being remarkably low, afforded me an opportunity of 

 ascertaining more accurately the time during which they have 

 continued to migrate, which has been nearly the whole of the 

 month, but more especially during the second week, in the 

 course of which the shoals were botli larger and more frequent 



