A simple generalization may make this clear.  The ordinary stock foliage of the Ornamentist was evolved in connection with: 

(In the West)         (In the East)
ARCHITECTURE,          TEXTILES,
as in Greece.          as in Persia.

Hence the primary Elements of decoration were derived from: 

(In the West)                     (In the East)
GEOMETRICAL LINES,                NATURAL FLOWERS and LEAVES,
e.g. the meander, spiral, etc.    e.g. the pine, pomegranate, etc.

Further, it may be observed that the Method of treating these Elements has been different: 

(In the West) (In the East) The Geometrical lines The natural foliage was were enriched by the introduction codified by the introduction of the details of of Geometrical arrangement; Natural vegetation; thus thus becoming becoming gradually more gradually more naturalesque. artificial.

An APPROXIMATION between the two treatments, sometimes appears; but the two kinds—­Artificial, and Natural—­are essentially different in origin; and should be kept distinct in their application.

This approximation may be shown, in a tabular arrangement, thus: 

GEOMETRY...............................................

............NATURE

The patterns are merely The plants are copied as straight lines, dots, and accurately as possible.
  portions of circles.

The lines become stems.  The plant is applied
without repetition.

Leaves are added to the             Repetition is used with the
stems.                            plants.

Serration is added to the       Weaving economy induces
leaf-edge.                    symmetry.

Similarity of serrated Symmetry induces Geometrical leaf-edge to the Akanthos Severity, and the Omission plant, is observed; of all details of the Imitation becomes more original plant which are not direct; and this artificial easily worked in connection foliage becomes termed with geometrical “Acanthus.” arrangement.

Flowers generally circular The Flowers and Leaves in mass-shape, are added (only) survive; the growth at the ends of the spiral of the stems is forgotten; stems. and tradition does the rest.

Sec. 3.—­APPLICATION OF THE TWO KINDS.

Each of these two kinds of foliage has its own proper use.  Artificial foliage is appropriate to the enrichment of Architecture; and Natural foliage to those objects which are not architectural, but are termed “movables,” including under this term, Furniture, and more especially Hangings and other applications of the Textile art.