Abstract
Single and concurrent infections of cecal trematodes, Z. lunata and Notocotylus spp., were studied in controlled, laboratory infections in the domestic chick. The recovery of Notocotylus sp. from the chick cecum was reduced significantly in the presence of Z. lunata. Neither size nor distribution of either helminth was affected by presence of the other. The ventral surface of Notocotylus sp. was associated intimately with the cecal villus, and this fluke fed on host blood.