42 
THE PRESERVATION OF SEA FISH 
Begin near the gills, and insert the blade carefully under a 
scale and plunge it in till it meets the backbone or a rib. Do 
not move it laterally nor raise or depress the blade, as this 
will break up the edges of the scales ; simply raise the scale 
with the point, plunge in the blade and then withdraw it. 
Do this at, say, the four corners of every square inch of skin 
surface, being careful not to puncture the intestinal area. 
Then rinse this specimen in water and immerse in the 
formalin solution. 
The second method is used when treating fish of deep 
girth or round-shaped tropical fish weighing from four to 
ten pounds. 
Make a line of three or more incisions two and a half inches 
long, and the same distance apart, right along the middle of the 
fish between the gill cover and the tail on the top of the back- 
bone; then insert the knife and free all the flesh as before 
explained ; make a one-inch opening in the vent, turn the fish 
over, and puncture it under the scales deeply as mentioned 
above. 
The third method is simply to puncture the fish under the 
scales on both sides and make the ventral incision. This 
practice is quite reliable for fish up to five pounds and produces 
unblemished specimens, but when it comes to handling heavy 
fish I much prefer the second method of free incisions. 
Many fish show a decided tendency to float in the solution 
and some refuse to sink at all. With all fish the air should 
be expressed by hand-pressure on their being placed in the 
solution. If after that they do not remain below the surface, 
place a small flat piece of stone in one of the incisions, never 
employ any metal or coins. It is essential that the specimens 
remain completely submerged, as the portion remaining out 
of the solution will inevitably lose all its colour very shortly, 
though complete preservation will most probably take place. 
If the fish are overcrowded in a tank and freshly caught 
specimens are introduced, there is also a danger of partial and 
local loss of colour, through some portion of the fresh specimen 
being kept in close contact with an old specimen in the tank 
I have seen specimens ruined, as regards colouration, in twenty- 
four hours by overcrowding. 
