of Holothuria nigra, [562];

of Antedon rosacea, [583];

of Dipleurula, [605]

Ogilvie, M., [401] n.

Oikomonadidae, [111]

Oikomonas, [111], [112]

Oil-drops, of Radiolaria, [79] f.;

luminous, [80]

Oil-globules, [37];

of Ciliata, [144]