n his _Flore Francaise_ appeared. It was not
preceded, as in the case of most botanical works, by any preliminary
papers containing descriptions of new or unknown species, and the three
stout octavo volumes appeared together at the same date.

The first volume opens with a report on the work made by MM. Duhamel and
Guettard. Then follows the _Discours Preliminaire_, comprising over a
hundred pages, while the main body of the work opens with the _Principes
Elementaires de Botanique_, occupying 223 pages. The work was a general
elementary botany and written in French. Before this time botanists had
departed from the artificial system of Linne, though it was convenient
for amateurs in naming their plants. Jussieu had proposed his system of
natural families, founded on a scientific basis, but naturally more
difficult for the use of beginners. To obviate the matter Lamarck
conceived and proposed the dichotomic method for the easy determination
of species. No new species were described, and the work, written in the
vernacular, was simply a guide to the indigenous plants of France,
beginning with the cryptogams and ending with the flowering plants. A
second edition appeared in 1780, and a third, edited and remodelled by
A. P. De Candolle, and forming six volumes, appeared in 1805-1815. This
was until within a comparatively few years the standard French botany.

Soon after the publication of his _Flore Francaise_ he projected two
other works which gave him a still higher position among botanists. His
_Dictionnaire de Botanique_ was published in 1783-1817, forming eight
volumes and five supplementary ones. The first two and part of the third
volume were written by Lamarck, the remainder by other botanists, who
completed it after Lamarck had abandoned botanical studies and taken up
his zooelogical work. His second great undertaking was _L'Illustration
des Genres_ (1791-1800), with a supplement by Poiret (1823).

Cuvier speaks thus of these works:

"_L'Illustration des Genres_ is a work especially fitted to enable
one to acquire readily an almost complete idea of this beautiful
science. The precision of the descriptions and of the definitions of
Linnaeus is maintained, as in the institutions of Tournefort, with
figures adapted to give body to these abstractions, and to appeal
both to the eye and to the mind, and not only are the flowers and
fruits represented, but often the entire plant. More than two
thousand g