We do not clearly see, and should have been glad had the author stated, in what manner he ascertained that his St Boswell's fish had not escaped the sweeping semicircles of the lower nets some days previous. We admit that there is a great deal of Sabbath desecration committed by salmon, but we also know that they travel upwards, though in smaller number and with greater risk, during all the other days of the week; and we are curious to understand how any angler, however accomplished, can carry his skill in physiognomy to such perfection, as to be able to look a fish in the face on Monday morning, and decide that it had not left the sea till the clock struck twelve on the Saturday night preceding. "As salmon" our author continues, "are supposed to enter a river merely for the purposes of spawning, and as that process does not take place till September, one cannot well account for their appearing in the Tweed and elsewhere so early as February and March, seeing that they lose in weight and condition during their continuance in fresh water. Some think it is to get rid of the sea-louse; but this supposition must be set aside, when it is known that this insect adheres only to a portion of the newly-run fish which are in best condition. I think it more probable that they are driven from the coasts near the river by the numerous enemies they encounter there, such as porpoises and seals, which devour them in great quantities. However this may be, they remain in the fresh water till the spawning months commence."--P. 10. We cannot think that a great instinctive movement which seems, although with a widely extended range in respect to tine, to pervade the entire mass of salmon along our universal shores, should in any way depend upon so casual an occurrence as an onslaught by seals and porpoises, or that fear rather than love should force them to seek the "pastoral melancholy" of the upper streams and tributaries. That seals are destructive to salmon, and all other fishes which frequent our shores or enter our estuaries, is undoubted; but we have no proof beyond the general allegation, that porpoises pursue a corresponding prey. Our own researches certainly lead to an opposite conclusion. The ordinary food of the _cetacea_, notwithstanding their enormous bulk, is minute in size; and we have never been informed, on good authority--that is, on direct testimony--that even herrings have ever been detected in the stomach of a porpoise. Yet we have careful notes of the dissection of these creatures, taken from specimens slaughtered in the midst of millions of herrings; and these notes show that the minute food with which the sea was swarming, and which formed the sustenance for the time of the smaller fishes, also constituted the food of the _cetacea_, which were merely gamboling through the herring shoals.