Fig. 4.

(A) Histological section of G. humilis exposed to H. americana miracidia, 8 days post exposure. Note presence of mother sporocyst developing in the head foot of the snail. Scale bar = 60 μm. (B) Histological section of G. humilis exposed to H. americana miracidia, 28 days post-exposure. Note presence of daughter sporocysts harboring developing cercariae in the digestive gland of the snail. Scale bar = 80 μm. (C) Live, unstained adult male of H. americana from experimental infection (101 days post-infection), dorsal view, with straight body conformation, testes (white spheres) visible at posterior end. (D) Live, unstained worms, adult male (left) harboring one female within its gynecophoric canal (note bulge containing folded female worm with dark gut and her protruding posterior end) and to the male's right, another female just released from its gynecophoric canal, from infected mouse, 77 days post-infection). Scale bar for adult worms = 500 μm.