550 MR SHAW'S EXPERIMENTAL OBSERVATIONS ON THE 



year, become bolder and more apparent, and now constitute the May and summer 

 parr of anglers. But their timid habits during the first few months of their ex- 

 istence, and their consequent concealment in the shingle, greatly screen them 

 from observation during that period, and have led to the erroneous belief, that the 

 silvery smolts were the actual produce of the season, and were only a few weeks 

 old. It certainly seems singular that it should never have occurred to any intel- 

 ligent angler to inquire what had become of the older generation of parr, that is 

 of the comparatively large individuals which he might have captured late in 

 autumn and in earliest spring, but none of which he can detect after the depar- 

 ture of the so-called smolts. If the two are not identical, how does it happen that 

 the one so constantly disappears simultaneously with the other ? Yet no one al- 

 leges that he has ever seen parr, as such, performing their migration towards the 

 sea. They cannot do so, because they have been previously converted into smolts. 

 I shall here allude briefly to three different occasions on which I have had 

 an opportunity of witnessing the first migration of smolts or converted parr, that 

 is, their descent in small shoals towards the sea. The first of these was in the 

 first week of May 183]. I was able dehberately to inspect them as the several 

 shoals arrived behind the sluices of a salmon cruive, and while they yet remained 

 in the water, and were swimming in a particular direction, indistinct transverse 

 lateral bars might stiU be seen, but as they changed their position, these became 

 as it were lost in the silvery lustre. I also examined many of them in the hand, 

 and could there also, by holding them at a certain angle in relation to the eye, 

 produce the barred appearance, but when the fish were held with their broad side 

 directly opposed to view, the character alluded to could not be seen. Its actual 

 existence, however, could be easily proved by removing the deciduous silvery 

 scales, when the barred markings became apparent, and, of course, continued so 

 to whatever light exposed. My next opportunity occurred on the 3d of May 

 1833. The appearance was exactly the same as that which I have just described. 

 They passed down the river in small family gi'oups or shoals of from forty to sixty 

 and upwards, their rate of progression being about two miles an hour. The cau- 

 tion which they exercised in descending the several rapids they met with in the 

 course of their journey was very amusing. They no sooner came within the in- 

 fluence of any rapid current than they in an instant turned their heads up the 

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

 brink, and as often retreat upwards, till at length one or two, bolder than the 

 others, permitted themselves to be carried over the current, when the entire flock, 

 one by one, disappeared, and then, so soon as they had reached comparatively 

 still water, they again turned their heads towards the sea, and resumed their 

 journey. The third opportunity to which I shall here refer occurred in May 1836, 

 at which time, as I have stated, I compared a few of the descending smolts with 

 those which (having been two years in my possession as parr) had, in the confine- 



