Stylostomum, [19], [22]

Sub-cuticle, [125], [175]

Submalleate, [210], [211]

Succinea putris, infested by larvae of Distomum macrostomum, [64], [66]

Sucker, of Leptoplana, [8], [16] n.;

of Triclads, [35], [36];

of Temnocephala, [53], [54];

of Monogenea, [53], [56], [57], [60];

of Digenea, [62], [64], [65], [69];

of Cestodes, [75], [79];