rchil,
cudbear, litmus, and other lichen dyes. While investigating the
dyeing properties of the lichens, I made experiments, with a view to
test their colorific power, on as many species as I could obtain in
sufficient quantity, to render it at all useful to operate on--that
number, however, being very limited (between forty and fifty).

Dr. Lindley adds, many parties may be able to aid his
investigations, by furnishing information on their economic uses,
and on their special applications in dyeing and other
arts--(particularly on their employment, as dye agents, by the
natives of Britain and other countries)--with specimens of the
lichens so used, and their common names--specimens of fabrics dyed
therewith--notes of the processes employed for the elimination of
the dyes, &c. Parties resident in, or travelling through our western
Highlands and Islands, the northern Highlands, Ireland, Wales,
Norway, Iceland, and similar countries, are most likely to be able
to afford this description of information--many native lichens being
still used by the peasantry of these countries to dye their homespun
yarn, &c.

He proceeded to treat--1. The vast importance of this humble tribe
of plants in the grand economy of nature, as the pioneers and
founders of _all_ vegetation. 2. Their importance to man and the
lower animals, as furnishing various articles of food. 3. Their
importance in medicine, and especially in its past history, at home
and abroad. 4. Their importance in the useful and fine arts, and
especially in the art of dyeing. 5. Their affinities and analogies
to other cryptogamic families, and to the Phanerogamia. 6. Their
value as an element of the picturesque in nature; and, 7. Their
typical significance.

He then adverted more especially to the subject of his
communication, under the ten following heads:--

I. The colors of the Thallus and apothecia of Lichens--their causes, and
the circumstances which modify and alter them.

II. History of the application of their coloring matters to the art of dyeing.

III. Chemical nature and general properties of these coloring matters.

IV. Tests and processes for estimating qualitatively, and quantitatively the
colorific powers of individual species--with their practical applications.

V. Processes of manufacture of the Lichen-dyes, on