| Author | Mann, K.H. & Watson, E.V. |
| Year | 1964 |
| Title | A Key to British Freshwater Leeches with Notes on their Ecology |
| Series | FBA Scientific Publication |
| Type | Book/Report |
| How Complete | Covers all UK species known at the time |
| Source | FBA Scientific Publication , No. 14, 2 edition, 50pp, Freshwater Biological Association |
| Illustrations | Copious line drawings and a single colour plate |
| Review (by Malcolm Storey) | A single colour plate, a dichotomous key to the species with line drawings, and chapters on biology, life history etc, plus 10 km distribution maps (although these are very old now). |
| Examine |  with x15 or x20 hand lens |
| Specimen Preparation | Living leeches may be anaesthetized in soda water and then examined while held between two microscope slides. Large black leeches may need to be killed and bleached for 20 mins in 5% KOH. |
| Identification difficulty | Adult leech identification uses the position of the eyes, and once these are seen it is straightforward. Coccoons are harder. |
