The setting board is put for two or three months in a very dry place
under cover from dust.
The spiders thus treated will scarcely have changed in appearance, the
abdomen of the largest Epeiras will have preserved its form, the hairs
will in nowise have become agglutinated, and a person would never
suspect that glycerine had performed the role.
The forms with a large abdomen require a special precaution; it is
necessary to pass the mounting pin through a piece of thin cardboard
or of gelatine prolonged behind under the abdomen, because the latter
is heavy, and the pedicel that connects it with the cephalothorax
easily breaks.
The specimens are mounted in boxes lined with cork, just as insects
are.
As there is nothing simpler than to have in one's laboratory three
bottles, two of them containing alcohol and the other containing
carbolated glycerine, and as it is easy to make setting boards capable
of holding from twenty to thirty individuals at once, it will be seen
that, with a little practice, the method is scarcely any more
complicated than the one daily employed for coleoptera and orthoptera,
which latter, too, must pass through alcohol, and be pinned, spread
out, and dried. There are but two additional elements, carbolated
glycerine and absorbent paper. I do not estimate the time necessary
for desiccation as being very long, since the zoologist can occupy
himself with other subjects while the specimens are drying. Let us add
that the process renders the preservation indefinite, and that
destructive insects are not to be feared. Some vertebrates, such as
monkeys, that I preserved in the flesh ten years ago, by a nearly
identical method, are still intact.--_F. Plateau, in Le Naturaliste._
* * * * *