Table 3.

Total number of Fasciola hepatica metacercariae in relation to the position of the host plant in the watercress bed. The width of the drainage furrow is expressed here in sections of 15 cm each.

Type of watercress bed	Length of the macrophyte-free zone (m)	Number of metacercariae per 15-cm wide section			Total number of metacercariae
		0.1–15	15.1–30	30.1–45
With a slow-flow spring	0.13–0.24	29	23	37	89
	1.1–1.8	35	27	19	81
	3.1–3.5	23	11	16	50
With a faster-flow spring	0.15–0.29	45	12	36	93
	1.3–1.6	26	7	18	51
	3.0–3.2	3	0	1	4