distribution of, [48];

associated with Euglena viridis, [124];

formerly included under Infusoria, [136];

vibratile styles of, [141]

Rotula, [548], [549]

Rotula of Echinus esculentus, [526]

Rotula muscles of Aristotle's lantern, [526]

Roule, [408]

Royal Society, early publications on Protozoa, [45]

Ruminants, infested by Trypanosoma evansii, [119];