fission of, [147]
Heteroxenia, [333], [335], [348]
Hexactine (a triaxon in which all six actines are developed), [184]
Hexactinellida, [194], [195], [197] f., [228], [240]
Hexadella, [196]
Hexamitus, [115]
Hexaster (a hexactine with secondary or terminal rays = Carter's "rosette"), [203]
Hexasterophora, [203] f.
Hickson, on interchange of cytoplasm in conjugating Infusoria, [149] n.;
on conjugation in Suctoria, [161] f.;