Salmo Salar seems to think that almost all the ova deposited naturally come to life, and that very few of those deposited artificially do so.  This, however, is quite contrary to my experience, and I think that if Salmo Salar will listen to the evidence he will change his opinion.  It is well known that Salmon are very fond of particular streams, their instinct no doubt informing them which are suitable to their purpose; and when one pair of fish have finished spawning, another pair will come and occupy the same place.  Now, what takes place under such circumstances?  The ova which were deposited by the first pair are rooted up by the second, and their specific gravity is so near that of the water, that they roll down out of the loose gravel and are picked up by the Trouts, Par, and other fish that are always lying in wait just below for that purpose.  When Ramsbottom was in Galway he caught a large Trout, out of whose throat he squeezed a thousand ova, which were deposited in a spawning-box, many of which came to life notwithstanding the pit they had escaped from.  The extraordinary avidity with which Trout take Salmon roe as a bait is also a proof (if that were needed) of their preying upon it in the spawning beds.  Yet, in addition to them, are all the Par, Bullheads, Eels, Loaches, and aquatic larvae which may be found swarming in every spawning bed by any one who will look for them.  In addition to these enemies, millions of the ova are destroyed by being washed away by heavy floods, and as many more are destroyed by being choked with mud and sand in the spawning beds as well as by being left dry at low water owing to the Salmon spawning in places which frequently become quite dry in early spring.  No doubt many of the Salmon fry when they have reached the sea are destroyed by enemies there, of which we know nothing.  But still, if 500,000 are bred, in addition to all that are reared naturally, it will represent a larger proportion of the whole than Salmo Salar seems to suppose; otherwise, how is it that in rivers where Salmon are protected, or still more in unsettled countries, the Salmon are so numerous?  The Salmon in the Columbia river, on the north-west coast of America, are cast dead upon the shores by myriads after the spawning season, and these are merely the fish dying from exhaustion, as a small portion always do here.  How numerous, then, are those which ascend the river to spawn, and go down again to the sea afterwards!  No doubt the grand object to be attained is to make Salmon abundant, and the most important step towards the attainment of this object will be to give an efficient protection to the spawning fish, and the only way to do this effectually is to give the upper proprietors of rivers such an interest in the Salmon fisheries as will make them worth attention.  At present this is far from being the case.  Now the upper proprietors are merely considered as so many clucking hens, whose business and whose duty it is to hatch