1. Structural, having reference to the form and structure of the various
parts, including (a) Morphology, the study of the general form of the
organs and their development--this will be treated in a series of
articles dealing with the great subdivisions of plants (see ANGIOSPERMS,
GYMNOSPERMS, PTERIDOPHYTA, BRYOPHYTA, ALGAE, LICHENS, FUNGI and
BACTERIOLOGY) and the more important organs (see STEM, LEAF, ROOT,
FLOWER, FRUIT); (b) Anatomy, the study of internal structure, including
minute anatomy or histology (see PLANTS: _Anatomy_).
2. Cytology (q.v.), the intimate structure and behaviour of the cell and
its contents--protoplasm, nucleus, &c.
3. Physiology, the study of the life-functions of the entire plant and
its organs (see PLANTS: _Physiology_).
4. Systematic, the arrangement and classification of plants (see PLANTS:
_Classification_).
5. Distribution or Geographical Botany, the consideration of the
distribution of plants on the earth's surface (see PLANTS:
_Distribution_).
6. Palaeontology, the study of the fossils found in the various strata
of which the earth is composed (see PALAEOBOTANY).
7. Ecology or Oecology, the study of plants in relation to each other
and to their environment (see PLANTS: _Ecology_).
Besides these departments which deal with Botany as a science, there are
various applications of botany, such as forestry (see FORESTS AND
FORESTRY), agriculture (q.v.), horticulture (q.v.), and materia medica
(for use in medicine; see the separate articles on each plant).
(A. B. R.)