crease of the species, (any more than we
could judge of the growth of a young English guardsman in the prisons of
Verdun,) after the period of their natural migration to the sea, and as
Mr Shaw's distance from the salt water--twenty-five miles, we believe,
windings included--debarred his carrying on his investigations much
further with advantage, he wisely turned his attention to a different,
though cognate subject, to which we shall afterwards refer. We are,
however, fortunately enabled to proceed with our history of the
adolescent salmon by means of another ingenious observer already named,
Mr Andrew Young of Invershin.

It had always been the prevailing belief that smolts grew rapidly into
grilse, and the latter into salmon. But as soon as we became assured of
the gross errors of naturalists, and all other observers, regarding the
progress of the fry in fresh water, and how a few weeks had been
substituted for a period of a couple of years, it was natural that
considerate people should suspect that equal errors might pervade the
subsequent history of this important species. It appears, however, that
_marine_ influence (in whatever way it works) does indeed exercise a
most extraordinary effect upon those migrants from our upland streams,
and that the extremely rapid transit of a smolt to a grilse, and of the
latter to an adult salmon, is strictly true. Although Mr Young's labours
in this department differ from Mr Shaw's, in being rather confirmatory
than original, we consider them of great value, as reducing the subject
to a systematic form, and impressing it with the force and clearness of
the most successful demonstration.

Mr Young's first experiments were commenced as far back as 1836, and
were originally undertaken with a view to show whether the salmon of
each particular river, after descending to the sea, returned again to
their original spawning-beds, or whether, as some supposed, the main
body, returning coastwards from their feeding grounds in more distant
parts of the ocean, and advancing along our island shores, were merely
thrown into, or induced to enter, estuaries and rivers by accidental
circumstances; and that the numbers obtained in these latter localities
thus depended mainly on wind and weather, or other physical conditions,
being suitable to their upward progress at the time of their nearing the
mouths of the fresher waters. To settle this point, he caught and marked
all the spawned fish which he