in Oligochaeta, [348], [379];

in Polyzoa, [471], [488]

Repetition of parts, [249]

Replacement of species, [300]

Reproduction (and Reproductive organs), of Leptoplana, [14] f.;

of Polyclads, [26], [30];

of Triclads, [31], [38], [39];

of Rhabdocoelida, [45], [47] f.;

of Temnocephala, [54];

of Polystomatidae, [57] f.;