86 
which shortly afterwards appears, represents the vital 
organs of the embryo fish, 
At the end of about 80 to 100 days from the deposition 
of the egg the fish has so increased in size that it bursts 
the “shell” and makes its débu¢ in the form represented 
at Fig. 3. The sac or umbilical vesicle attached to the 
under part of the fish contains a secretion resembling 
albumen, which affords nourishment to the infant fish for 
the first six weeks or so of its existence. By that time it 
is quite absorbed, and for the first time we see a perfect 
Fic, x. Fic. 2. 
Fig, r=New-laid Salmon Egg. Fig, 2.—Egg after about 35 days. 
fish, Fig. 4, with its fins, gills, and scales, which have 
hitherto been present, but imperceptible except under the 
microscope, fully formed: and now the young salmon 
begins to feed. His growth is not very rapid for some 
months, the lines a 4 ¢ representing the average length 
of a salmon at 2, 3, and 4 months old. At 2 years old 
the fish is about 9 to 12 inches long. 
As soon as they are large enough and strong enough, 
the “ smolts,” as they are now called, descend to the sea ; 
here they are lost sight of until they return up the river as 
 srilse.” The actual duration of their stay in the sea is 
not yet known, from one to three years being variously 
estimated as the probable length of time. The object of 
this migration to the sea is to find the food which is 
necessary for the secretion of the fat of the fish, who lives 
on the Znfusoria, smaller fish and crustaceans, and the 
spawn of sea-fish which abound in our seas, The 
length of their stay in salt-water is regulated, no doubt, 
by various circumstances, and is not the same in every 
case. When the salmon has laid up a sufficient supply 
of fat in its body and on its pyloric appendages, which 
are a wonderful provision of Nature for the secretion of 
an amount of fat sufficient to supply it during its sojourn 
in fresh waters, it ascends the river, its roe or spawn 
developing as it ascends; till, about Christmas-time, or 
sometimes earlier, it reaches the shallow headstreams of 
the river, in the gravelly beds of which it deposits its 
eggs, returning immediately afterwards to the sea, no 
Fic. 3.—Fish coming out or egg. 
longer in the bright, plump, muscular condition in which 
it ascended, but a lean, lank, ugly, wounded beast, which 
one would hardly recognise as Salmo salar. Fig. 5 
represents the head of a “ kelt,” as those salmon are called 
which haye newly spawned. The curved projection, or 
hook, on the lower jaw, is a cartilaginous membrane, the use 
of which nobody knows. The fish is in a very weakly con- 
dition, as his fat is gone, and he perhaps assumes this 
appearance, to frighten other animals, which might 
otherwise be tempted to attack him. The drawing 
is taken from the photograph of a salmon, weighing 
20lb., which was found dead on the banks of one off our 
Welsh rivers, al & Lo sertol Of 
NATURE 
v 
Toe AS pol ee ee eter 
, ‘ 7 
[Axug. 7, 1873 
This fish, had it survived, would have returned to sea, 
recovered its fat, and presently come back worth 2/. or 
3/., whereas, by dying in this condition, it was worth 
nothing. It had, however, done its duty by depositing 
perhaps 16,000 eggs. Only a very small percentage, 
however, of the eggs laid ever become adult fish. Floods 
wash them out of their gravel nests; ducks, and other 
birds, eat them; beetles and ‘warious insects attack 
them ; they are smothered with mud, or left high and 
dry on the shore; the young fish are poisoned by pollu- 
«1 P 
Fic, 4.—Young Salmon six weeks old. a, 2, c, size of salmon at two, three, 
and four months respectively. 
tions, or diverted into mill leats and canals, and so lost ; 
trout eat them wholesale; in fact the whole of their 
earliest existence is a very living death, and it is a wonder, 
with all the ordeals they have to pass through, that we 
have any salmonleft. To kill them legitimately for food for 
ourselves is bad enough, and we ought to do all we can 
to protect them when young. 
In the artificial system of breeding salmon the adult 
fish are caught just as they are on the spawning beds, and 
the eggs taken from them ; the ova and milt are properly 
mixed together, and the eggs placed in troughs of water 
so arranged as to imitate as closely as possible the natural 
conditions necessary for the development and growth of 
the fish, Properly managed, go per cent. of the eggs will 
hatch out ; the young fish are turned into the river when 
they are about a year old; if they can be kept two years 
in tanks large enough, with plenty of running water, so 
Fic. 5.—Head of a Kelt. 
much the better for the prospect of their reaching the 
sea in safety. 
When we can make up our minds to keep all our pollu- 
tions out of our rivers, and build ‘salmon ladders” over 
all the weirs, so as to give the fish a fair field, and enable 
them to run up stream unimpeded, then, and then only, 
shall we see salmon as plentiful throughout the country 
as it is said to have been in the North a century ago, 
when apprentices are reputed to have stipulated in their 
indentures that they should be fed on salmon not more 
than three days a week. Without this all our efforts to 
stock our barren rivers with artificially bred fry will prove 
comparatively unavailing. C, E, FRYER 
