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ones. For short periods of time lacquered or tinned cans and drums may be 
used. Ordinary cans and drums may be used by lining them with plastic 
bags. Five-gallon cans with wide lids are a convenient size. Fibre-glass 
containers when made with an alcohol-proof base are excellent. New 
barrels of light-coloured wood may be used for temporary storage, except 
in hot countries. 
Shipping 
Only after fixing about a week, may specimens be shipped. Collections 
of small fishes may be wrapped with a label in gauze and tied lightly with 
string. Burlap or other coarse cloth is not suitable. Larger fishes should be 
wrapped with a label in gauze, individually. Or plastic bags with a 
small amount of fluid put in each bag may be substituted for gauze. These 
parcels are then lightly packed in a waterproof container with a small amount 
of fluid. Empty space is filled so that specimens do not knock about. 
Fill with cloth, w T hite paper, or white wood chips. The container should be 
sealed. If shipped for long distances metal containers should be soldered 
closed as a surprising amount of fluid may evaporate through a small hole. 
Small lots can be conveniently mailed in cans sealed with a home-canning 
machine, in sealed plastic bags (except for spiny specimens), inside boxes or 
mailing cartons. 
An address label should be included on the inside and the outside of each 
shipment. An outer label should also state “Scientific specimens of fishes, 
no commercial value, ” with the addition of “Replacement value I — ” in 
the case of rare or valuable specimens. 
Preservatives 
Two standard field preservatives are used, 10 per cent formalin and 
70 per cent ethyl alcohol. Alcohol is bulkier to take into the field and 
preserving in it requires more time and care; however it is more agreeable 
to work with and will not freeze in cold weather. Alcohol is also more 
expensive (unless the tax is rebated to the institution), and there may be 
legal problems. Formalin is less bulky to carry into the field, requires less 
trouble in preservation, gives greater certainty of preservation; but it is less 
agreeable to work with and freezes in cold weather. Most modern collectors 
use formalin. 
In the museum, specimens are stored permanently in 45 per cent iso- 
propyl alcohol or in 70 per cent ethyl alcohol (occasionally in 10 per cent 
buffered formalin). If the specimens have been in formalin, they are soaked 
24 hours or more in w r ater to wash it out before they are transferred to 
alcohol. Colours keep better when specimens are stored in the dark. 
Formalin (Formol) 
Commercial concentrated formalin usually consists of 37 per cent 
formaldehyde gas (CH 2 0) in w r ater plus some methyl alcohol to prevent 
polymerization. It is poisonous, irritating to inhale, and painful to abraided 
skin. A 10 per cent solution (of the concentrated form by volume) is made by 
adding 1 part of concentrated formalin to 9 parts of water. 
As formalin is acidic and decalcifies bones and scales, it should be 
buffered particularly when specimens are left in it for some time. This may 
be done (Miller, 1952) by adding: 
