XXXll 
European Ferns. 
practical purposes. We may, if we please, either attach our specimen firmly to the paper 
by gumming it all over on the under side, as is done in the British Museum — the gum used 
being a mixture of tragacanth and gum arabic in equal proportions — or we may fasten it 
to the sheet by means of gummed strips of paper (which, by the way, will be needed in 
the former case for the ends of the stems) ; the advantage of this latter system is, of course, 
that the specimen so fastened can, when necessary, be transferred from one sheet to another 
without injury. Some have adopted the plan of sewing the fern to the paper ; the appearance 
of specimens so arranged is very neat, but the process is rather tedious, and not unattended 
with danger to the specimen, so that we do not recommend it for adoption. 
The sheets being thus duly prepared, the next question is — how to arrange them. First, 
however, the specimens must be labelled, each label supplying the name of the fern, with the 
locality where it was found and the date when it was collected, adding also the collector’s 
name and any other information relative to the specimen which may be of special interest. 
The plan which is adopted by many botanists of writing all necessary information upon the 
sheet itself is a very good one; some, however, prefer a uniform series of iabels, and the 
following form will be found simple and useful for the purpose : — 
Herb. John Smith. 
P ter is aquilina , L. 
Bracken. 
Loc. — Hampstead Heath, Middlesex. 
Date. — June 12, 1876. 
Coll. — John Smith. 
For purposes of ready reference the sheets should be arranged in stiff covers of somewhat 
stouter paper than that upon which the specimens arc mounted. The name of the genus 
may well be written in the bottom left-hand corner ; in the centre may be noted a reference 
to the manual or list by which the ferns are arranged, while the names of the species may 
be written in the right-hand corner. Should the ferns be represented by more than one sheet, 
it may be convenient to enclose each species in a cover of thinner paper, writing the name 
in the right-hand corner. The herbarium must, of course, be kept in a dry place, as damp 
favours the growth of mould. If there is any fear of the attacks of insects, it is well to wash 
the specimens over with a solution of corrosive sublimate ; the solution in use at the Kew 
Herbarium is composed of one pound of corrosive sublimate and the same quantity of 
carbolic acid to four gallons of methylated spirit ; this is found very efficacious, but its smell 
is somewhat unpleasant. At the British Museum it is found that camphor kept in each 
cabinet, and frequently renewed, is sufficient to prevent the appearance of insects in the 
herbarium. 
Last of all comes the question — Where and how shall we keep our ferns when they are 
in a condition to be consulted ; when collecting, and naming, and drying, and mounting are 
