ying such
an iron, as some persons do, with great labor and perseverance, till the
plants are quite dry, and all their parts incorporated into a smooth
flat mass is not approved of. This renders them unfit for subsequent
examination, and destroys their natural habit, the most important thing
to be preserved. Even in spreading plants between papers, we should
refrain from that practice and artificial disposition of their branches,
leaves, and other parts, which takes away from their natural aspect,
except for the purpose of displaying the internal parts of some one or
two of their flowers, for ready observation. The most approved method of
pressing is by a box or frame, with a bottom of cloth or leather, like a
square sieve. In this, coarse sand or small shot may be placed; in any
quantity very little pressing is required in drying specimens; what is
found necessary should be applied equally to every part of the bundle
under the operation.

Hot-pressing, by means of steel net-work heated, and placed in alternate
layers with the papers, in the manner of hot pressing paper, and the
whole covered with the equalizing press, above described, would probably
be an improvement, but we have not heard of its being tried. At all
events, pressing by screw presses, or weighty non-elastic bodies, must
be avoided, as tending to bruise the stalks and other protuberant parts
of plants.

"After all we can do," Sir J.E. Smith observes, "plants dry very
variously. The blue colours of their flowers generally fade, nor are
reds always permanent. Yellows are much more so, but very few white
flowers retain their natural aspect. The snowdrop and parnassia, if well
dried, continue white. Some greens are much more permanent than others;
for there are some natural families whose leaves, as well as flowers,
turn almost black by drying, as melampyrum, bartsia, and their allies,
several willows, and most of the orchideae. The heaths and firs in
general cast off their leaves between papers, which appears to be an
effort of the living principle, for it is prevented by immersion of the
fresh specimen in boiling water."

The specimens being dried, are sometimes kept loose between leaves of
paper; at other times wholly gummed or glued to paper, but most
generally attached by one or more transverse slips of paper, glued on
one end and pinned at the other, so that such specimens can readily be
taken out, examined, and replaced. On account of the aptitude