Bruce, Col. and Mrs., on Trypanosomic fever and sleeping sickness, [120]

Bubbles of carbon dioxide formed in Arcella, etc., [53]

Buccal sinus of Holothuria nigra, [566]

Buccal tentacle—see Buccal tube-foot

Buccal tube-foot (and tentacle), of Ophiothrix fragilis, [486];

of Echinus esculentus, [518];

of Echinocardium cordatum, [551], [561];

of Holothuria nigra, [561];

of Spatangoidea, [577];

development of, in Holothuroid pupa, [615]