PRESERVATION OF COLEOPTERA. 51 
give the required proficiency. The best kind of cardboard for 
the purpose is “ Bristol.” It should be cut into convenient slips, 
large enough for a row of six or seven insects. The beetles can 
be separated by a pair of small scissors as soon as the gum is 
quite dry, and the sides and ends having had all superfluous card- 
board cut away, each insect can be labelled and placed in the 
setting-house to dry. 
Many collectors mount their specimens with gum-arabic only. 
It is objectionable, because when dry it leaves a certain amount 
of gloss. A much better plan is to use a mixture of gum-traga- 
canth and gum-arabic. After a good deal of experience, I can 
recommend the following method for the preparation of the 
mixture. Take a small wide-mouthed bottle with glass stopper, 
put into it a small clear piece of gum-tragacanth about the size 
of the finger-nail, and just cover it with clear water; in a few 
hours add a teaspoonful of water, and next morning a similar 
quantity, do the same the following day; by that time the gum 
will have absorbed all the water and become much swollen and 
soft, but if it appear too dry a little more water may be poured 
on it, and then, but not till the third day, it may be well stirred. 
It should then be so thick that none would come out of the bottle 
when turned on its side, and in that state would be unsuitable 
for mounting insects ; but by adding two or three pieces of gum- 
arabic, and stirring them well, the mixture will become some- 
what liquified and just of the right consistency. If the two sorts 
of gum are put into the bottle at once, covered with water, and 
frequently stirred, the gum-tragacanth will only partially dissolve 
and form very minute lumps, which will appear unsightly and 
seriously interfere with the setting-out of small beetles. The 
mixture will keep in good condition for a month or more, but it 
is better to make a small quantity only and renew it before it can 
become mouldy. 
Before the specimens are placed in the cabinet or store-boxes, 
they should be cleaned with a camel-hair brush dipped into 
benzine, and if mould should appear subsequently they should 
be again treated in the same way. 
Enough I hope has been written to enable any intelligent in- 
dividual to find and preserve a sufficient number of beetles to 
form a tolerably good collection. I am well aware that many 
little details as to capture and manipulation have been omitted, 
but experience and perseverance will supply their place much 
better than written directions. If complete instructions for the 
finding of beetles had been written, a detailed history of the 
modes of life of every group, and indeed of very many genera 
and species must have been given, and in the case of setting-out 
a similar course must have been pursued with reference to struc- 
ture. 
