of Haemosporidae, [102] f.;

of Sarcocystis tenella, [108] n.;

of Volvocaceae, [128] f.;

of Eudorina, [129];

of Peritrichaceae, [151] f.

Sex, ternary, of Pandorina, [128] f.

Sexual fusion of Halteridium, [103], [105]

Sheath, tentacular, of Suctoria, [159]

Sheep, host of Sarcocystis tenella, [108] n.

Shell, of Diatomaceae, [84];