The terrestrial leech, Haemopis terrestris

Includes bibliographical references.Includes illustrations.A study of the autecology of the terrestrial leech Haemopis terrestris was conducted. The research involved field and laboratory studies to determine some of the. environmental conditions which favor or limit the distribution of the leech. Parameters investigated were soil chemistry, moisture, temperature and food. The soil chemistry investigation failed to show statistically, except for nitrates, any significant differences between distribution of Haemopis terrestris and chemistry factors studied. When evaluated statistically, the leeches in their natural habitat were found to be distributed evenly in the temperature gradient of 13.0 to 17.5° C and moisture gradient of 28.9 to 45.0% water by weight. Under laboratory conditions the same statistical treatment showed them to be unevenly distributed along a temperature gradient of 13.5 to 17.5° C. Experimentally, an uneven distribution was also detected along the moisture gradient of 43.2 to 74.9l. These results indicate that the leech prefers soils with relatively low temperatures but has a wide toleration range for moisture content. Experimental as well as laboratory observations indicate that the chief foods of the leech are earthworms and the smaller of its own kind.M.S. (Master of Science