Oswald Tippo published a plant classification system in 1942 that was derived from Gilbert Smith's earlier system. Tippo's system divided plants into two subkingdoms: Thallophyta, which do not form embryos; and Embryophyta, which do form embryos. Embryophyta are further divided into non-vascular plants like mosses and liverworts, and vascular plants divided into four subphyla based on their conducting tissues and other features. Tippo's system was popular among American writers.

1. Classification System
Of
Oswald Tippo
Prepared By:
Nasir Abbas
Zoo-19-48
2nd Semester

2.  Oswald Tippo published outline of the classification of the
plant in 1942.
 This classification was derived from classification of Gilbert
Smith.
 This system popularly used by American writers.
Common Features

3. Oswald Tippo
Classification
Thallophyta
Thallus like plant Body
Do not form embryo
EmbryoPhyta
Form Embryo

4. The scheme of classification of Tippo is:
 Subkingdom Thallophyta
These plant do not form embryo. It is further
divided into following phyla.
i. Cyanophyta (Blue green algae)
ii. Euglenophyta( Flagellate like Euglena
iii. Chlorophta ( Green Algae)
iv. Chrysophyta (Diatoms)
v. Phaeophyta ( Brown Algae)
vi. Rhodophyta ( Red Algae)
vii.Pyrrophyta ( Dinoflagellate)
viii.Schizomycophyta
ix. Myxomycophyta
x. Eumycophyta

5.  Subkingdom Embryophyta
They are embryo forming plants. They are further divided into:
Non-vascular Plants; For Example; Mosses,
Liverworts and hornworts
Vascular plant:
i. Subphlum psilopsida are leafless and rootless plant;
Psilotum
ii. Subphylum Lycopsida have simple vascular tissue and
small leaves ; Selaginella
iii. Subphylum Sphenopsida commonly called horse tail,
jointed stem and reduced scale like leaves; Equistum
iv. Subphylum pteropsida have complex conducting tissues,
large leaves and all advance characters;
a. Ferns
b. Gymnosperms
c. Angiosperms
}1.Bryophyta
2. Tracheophyta