f
littoral birds. Amongst those of the first we may instance Limnoea
stagnalis, palustris, peregra, etc, Dreissena polymorpha, Planorbis
corneus, etc.; the various Unios, anodons, and many others.

Amongst the land shells very many of the Helices, such as the
gaily-coloured nemoralis, or its variety hortensis, caperata,
arbustorum, cantiana, etc, as well as many other specimens.

The preservation of most freshwater and land shells is exceedingly
easy, the greater number of specimens requiring only to be plunged
into boiling water, and the contents removed--an easy operation in the
case of the bivalves, and the contents of univalves or snail-like
shells being also easily wormed out with a pin or crooked awl.
[Footnote: Mr. R. B. Woodward, F.G.S, etc. in one of the very best and
most practical of those wonderful little penny "Handbooks" for young
collectors, advises a large spoonful of salt being added to the
boiling water, for two reasons, one, because it puts them out of pain
at once, and also makes their subsequent extraction more easy. "It is
a good plan (says he) to soak the smaller shells in cold water
(without salt), before killing them, as they swell out with the water,
and do not when dead retreat so far into their shells."]

For works on shells see "Manual of the Mollusca," by Dr. S. P.
Woodward, J. Gywn-Jeffreys' "British Conchology," Lovell Reeve's
"British Land and Freshwater Mollusks," and several clever articles in
Science Gossip and the Conchological Journal, by Mr. G. Sherriff Tye
and others.

Glue is sufficient to fix all these objects in their places on
rockwork, in cases; resins, such as mastic or shellac, or any of the
cements mentioned in Chapter IV, are, however, the best mediums to fix
such objects upon tablets for scientific purposes. For fixing shells
on labelled cards, Mr. Woodward recommends gum arabic, with one-sixth
of its bulk of pure glycerine added to it, which makes a semi-elastic
cement, with the advantage also of allowing the shells to be taken
from their tablets, at any time, by the intervention of hot water.

DRYING AND STORAGE OF SPECIMENS.--It is always a vexed question how to
keep newly-mounted specimens free from moths, and flies, and dust,
whilst drying. The difficulty is, that you cannot put them away at
once in boxes, cases, or shades, for if you do they do not dry at all,
but "sweat" and slowly rot, or else become mildewed. If you expose
them fully without any covering,