Leeches lead a parasitic mode of life, by sucking the blood of vertebrates.
The adaptations are :
- Blood is sucked by the pharynx.
- Anterior and Posterior Suckers are provided, by which the animal attaches itself to the body of the host.
- The three Jaws, inside the mouth, causes a painless Y – shaped wound in the skin of the host,
- The salivary glands produce Hirudin, which does not allow the blood to coagulate. So, the continuous supply of blood is maintained
- Parapodia and Setae are absent.
- Blood is stored in the crop. It gives nourishment to the leech for several months. So there is no elaborate secretion of the digestive juices and enzymes.
