Swims by waves of contraction of longitudinal muscles. Some can ingest between 2 and 10 times their own weight in blood.
Water is removed from the blood and excreted through the nephridia.
Then digestion proceeds very very slowly. Medicinal leeches have been reported to go without food for 1.5 yrs. They may require 200 days to digest a meal. Pseudomonas hirudinicola, which lives in Hirudo medicinalis, breaks down high-molecular wt. Uses Return to Top Long history of use in medicine.