Classification:

• Phylum- Platyhelminthes
• Class- Turbellaria
• Order- Tricladida
• Genus- Planaria (Dugesia)

Comments:

1. 1.It is found in the freshwater streams, springs, ponds and lakes under the stones throughout the temperate zones.
2. 2. Planaria is found in India, Myanmar, U.K., U.S.A. and U.S.S.R.
3. 3. Body of Planaria or Dugesia is elongated, bilaterally symmetrical and dorsoventrally flattened.
4. 4. They are 2-15 mm in length and brown to black in color
5. 5. Head is triangular with conspicuous auricles and two eyes.
6. 6. Digestive system consists of the mouth, proboscis, pharynx and branched intestine.
7. 7. Mouth is situated on the ventral surface behind the middle of the worm
8. 8. Proboscis is enclosed in the proboscis sheath.
9. 9. Intestine forks into three diverticulated branches, one anterior and two posterior.
10. 10. Genital pore is situated a little posterior to the mouth
11. 11. Reproduction sexual, asexual and by regeneration.
12. 12. Planarians are extensively used for experimental purposes, e.g., regeneration and grafting etc.

Source:

1. Practical Zoology Invertebrates by S.S.Lal. 2. A Manual of Practical Zoology Chordates by Dr. P.S. Verma.