Dr. Vikas Meashi summarized Fritsch's 1945 book that classified algae into 11 classes based on pigments, food storage, reproduction type, motility, and flagella. The classes included Chlorophyceae, Xanthophyceae, Chrysophyceae, Bacillariophyceae, Cryptophyceae, Dinophyceae, Chloromonadineae, Euglenineae, Phaeophyceae, Rhodophyceae, and Myxophyceae. Examples were provided for each class.

1. Dr. Vikas Meashi

2. Algae Classification by Fritsch
F.E. Fritsch (1945) published in his book “The
Structure and Reproduction of the Algae”, New
system of Classification.
Fritsch divided the algae into 11 different Classes.

3. 11 classes of Algae
1. Chlorophyceae
2. Xanthophyceae
3. Chrysophyceae
4. Bacillariophyceae
5. Cryptophyceae
6. Dinophyceae
7. Chloromonadineae
8. Euglenineae
9. Phaeophyceae
10. Rhodophyceae
11. Myxophyceae

4. Criteria taken for Classification
• Pigments
• Nature of reserve food material
• Mode of Reproduction
• Motility
• Photosynthetic products
• Type of flagella

5. • Generally algae are fresh water and chlorophyllous
thallophytes.
• Chlorophyll b and carotenoides are present in
chloroplasts.
• The cell wall is made up of cellulose and food is
synthesized in the form of starch.
• Motile spores and cilia are found. The sexual
reproduction is isogamous, anisogamous and oogamous
types.
• Eg. Volvox, Chlamydomonas, Chlorella, Scenedesmus,
Ulothrix, and Spirogyra

6. 1. Desmotetra, 2. Stigeoclonium, 3. Desmodesmus. 4. Chlamydomonas, 5. Pediastrum, 6.
Volvox

7. • These are green-yellow in colour due to the
presence of xanthophyll.
• The pyrenoids are absent and food is in the
form of fat.
• Chlorophyll e is found in place of chlorophyll
b.
• The sexual reproduction occurs by fission of
two gametes having cilia of different length.
• Eg. Microspora, Vaucheria,

8. Vaucheria

9. • Mainly found in Cold Fresh water but some are
marine also
• Phycochrysin, Chl A and C
• In these organisms, besides chlorophyll, yellow-
green pigments are present.
• Phycocyanin is the colouring material.
• These are unicellular, multicellular or colonial.
• The cell wall is present in the form of two
overlapping halves and stored food is in the form
of oil or insoluble carbohydrates, leuosin.
• Eg. Chrysosphaera

10. 1. Dinobryon 2. Chrysospeara

11. • These are yellow-green-brown or olive green in colour.
• Diatomin is the colouring material which is found in
chloroplast.
• Chromatophores are yellow or golden brown.
• Pyrenoids are also present.
• Reserve food material: Fat or Volutin
• These are unicellular and non- motile.
• Chlorophyll c is present in place of chlorophyll b.
Eg. Pinularia, Navicula, Fragilaria

12. 1. Pinullaria 2. Fragilaria

13. • Found both in fresh and marine water
• Chromatophores show diverse pigmentation
• These are red, green-blue, olive-green or green
coloured algae.
• Each cell consists of two large chloroplasts in
which pyrenoids are present.
• Motile and coccoid, Flagella are slightly unequal .
• Example: Cryptomonas, Chroomonas

14. 1. Chroomonas 2. Cryptomonas

15. 6. Dinophyceae
• These are dark yellow or brown or red coloured
algae.
• Occurs widely as sea water plankton.
• Unicellular motile to branched filamentous
• Stored food is oil or starch.
• Large nucleus and many discs like
chromatophores are present.
• Example: Peridinium, Ceratium, Dinoflagellate

16. Ceratium

17. • These algae are bright green or olive green
colour.
• Xanthophyll is in abundance.
• Fatty compounds acts as food.
• Reproduction takes place by longitudinal division.
• Motile flagellate with two almost equal flagella.
• Example: Vacuolaria.

19. • Only Fresh water forms are reported.
• They resemble microscopic animal due to
presence of naked ciliated reproductive organs.
• Flagella may be one or two arise from the base of
canal.
• Storage material: Polysacharides, Paramylon
• Chromatophores are pure green in color.
• Chlorophyll is present.
• Example:Euglena.

20. Euglena sp.

21. • These are yellow-brown coloured marine algae.
• Fucoxanthin pigment is the main colouring
material, chlorophyll a and carotene are also
found and chlorophyll c is found in place of
Chlorophyll b.
• Storage food materials are laminarian, mannitol
and fats.
• Zoospores are bi-ciliated and one cilium is larger.
There is no resting period in zygote.
• Examples: Fucus, Sargassum.

22. 1. Sargassum 2. Fucus

23. • These are commonly found in sea water.
• These are red in colour due to phycoerythrin pigment.
• Phycocyanin, chlorophyll a, carotene and xanthophyll
are also present in small quantities.
• Storage food is floridean starch.
• Non-motile cells are found during reproduction.
• Sexual reproduction is oogamous type. Carpospores
are produced after reproduction.
• Chlorophyll d is present in place of chlorophyll b.
• Examples:
• Polysiphonia and Batrachospermum.

24. 1. Batrachospermum 2. Polysiphonia

25. • The nucleus is of prokaryotic type.
• Reserved Food: Starch & Glycogen
• Storage food is myxophycean starch and protein granules
• The blue colour is due to the presence of phycocyanin pigment
but phycoerythrin, chlorophyll b and carotene are also present in
small quantity.
• The accessory pigment (i.e., phycocyanin, phycoerythrin and
allophycocyanin) contains structure is called phycobilisomes.
• The chlorophylls are found in thylakoids.
• There is no motile stage in these algae. Sexual reproduction is
absent. Mainly these algae are unicellular or filamentous.
• Examples: Nostoc, Oscillatoria, Anahaena, Lyngbya, Plectonema.

26. 1. Osillatoria 2. Nostoc