viviparous species, [117]

Thalamoporella, [530]

Thalassema, [411], [435] f., [441], [443];

development, [439];

habits, [443]

Thelepus, [299], [329]

Theodisca, [321]

Thompson, J. V., on term Polyzoa, [475]

Thoracic membrane, [266], [305]

Thorax, of Polychaeta, [259], [306], [337]