Butterflies, when netted, can be easily killed by a prolonged sharp
pinch under the thorax before being taken from the net, and do not
need to be put into a poison-box. The pinch should be given between
the finger and thumb, the wings of the insect being kept in an upright
position.
Moths must be put into a poison-bottle or box, and left there from
twelve to twenty-four hours. Some varieties die much quicker than
others. Various kinds of poison are used for the boxes and bottles, but
cyanide of potassium seems most generally approved of by entomologists.
To catch moths, many people use the sugaring process. A mixture, made
of beer, rum, and coarse sugar or treacle, boiled till it becomes
thick like treacle is placed at night on the trunks of trees or on
flowers, and a lamp is placed near the sugared plants. True votaries
of “sweetness and light,” the moths alight on the sticky mixture, and,
becoming stupefied with the beer and rum, as a rule fall to the ground,
where they can easily be caught or netted.
Setting-boards are made of strips of wood about one foot or eighteen
inches in length, varying in width according to the size of the
specimen one wishes to pin out on it. These boards are covered with
sheet cork, having a groove down the middle to receive the body of the
insect. Some boards have a flat, others a slightly curved surface, and
these are covered with white paper. English entomologists generally use
curved boards, but foreign collectors prefer the flat setting-boards.
These latter seem somewhat preferable.
The good appearance and value of a collection greatly depend on the
setting, and for this reason much care and patience is required. The
butterfly should be taken between the thumb and finger of the left
hand, and an insect-pin inserted in the middle of the thorax, bringing
the point slightly sloping backwards and out at the legs. Then having
selected a board suitable in size to the specimen, it should be
pinned exactly in the middle of the groove, the body being kept quite
straight. Two narrow strips of paper, not more than ⅛th of an inch in
width, are now required to fasten down the two wings on each side of
the groove. Let each strip be pinned in front of the two fore-wings,
holding the end of a strip in the left hand; then very gently place the
wings, first the fore and then the hind-wing, in position, bringing
them forward with a long pin (the point being placed on the wings as
near the body as possible) in the right hand. At the same time the
strip of paper which is being held in the left hand is gently lowered
and fastened with a pin immediately below the hind-wing. Great care
must be taken not to injure the plumage by touching it. A second strip
of paper is now necessary on each side to pin down the outer edges of
the wings; but the first two strips are the most important ones, as
they keep the wings in position, and the latter may be very easily
added. The antennæ should be straightened and placed under the first
two strips of paper, or placed in position by two pins. The paper is
fastened along the boards, fixing as many specimens as its length will
permit.
Many persons use triangular pieces of card as braces for the butterfly,
fixing one or more on each wing, but the strips of paper seem somewhat
easier to arrange, and damage the plumage even less than the card,
though when either method is adopted the specimen ought not to be
damaged in the least. In making a perfect collection of butterflies
three specimens should be set up of every variety; the male, the
female, and one set with the underside uppermost. It is not usual to
set moths the reverse way.
Butterflies must be left on the board to stiffen for ten days or a
fortnight; after that they can be removed to the store-box. Moths with
large bodies take longer in drying, and must be left for three or four
weeks. By touching the end of the body of a specimen gently with a
pin it can easily be seen whether it is firm and stiff enough to be
removed to the case. If butterflies and moths are not set soon after
death they become stiff, and would be useless; but there are several
modes of relaxing them, and it may be useful to give a description
of the process which is generally adopted. Procure a marmalade-pot or
earthenware jar, into which put three inches of sand; pour on the sand
enough water to wet it thoroughly, without allowing the water to appear
on the surface. It is as well to put a small quantity of carbolic acid
with it. The insects to be relaxed should be pinned on to a thick
piece of cork, the cork resting on the top of the sand. Close the
mouth of the jar with a piece of glass, or something which will make
it air-tight. A few hours is often enough to relax specimens, but if
left longer they must be carefully watched, as they very soon become
mouldy. To keep the insects free from mites, napthaline must be freely
used in the store-boxes and cases. Camphor is used by some persons,
but napthaline is a far more efficacious preventive of the ravages of
parasites.
In packing specimens already set for England, store-boxes will hold a
great number if the specimens are judiciously placed one over the other
in a sloping manner, great care being taken that they do not touch each
other, as the slightest rubbing spoils the plumage.
Don Ramon Gomez, chemist, of Puerto Orotava, Teneriffe, has all
necessaries for the collector, such as setting-boards, store-boxes,
pins, etc., etc., and is most obliging in packing specimens for England
and giving any advice.
Many interesting objects for the naturalist and antiquarian may be seen
in his large collection, his Guanche remains being especially deserving
of notice.
Part I.