The large, extranuclear centrioles of Pseudotrichonympha are more elongate than in any known cell. Their distal portions degenerate in the late telophase and are resorbed, but are renewed in the early prophase of the next cell division. The distal portion of each centriole is surrounded by a hyaline centrosome through which the fibres of the achromatic figure arising from the centrioles pass. The achromatic figure is composed of 3 types of fibres: those of the central spindle, which is formed by astral rays meeting and overlapping ; the extranuclear chromosomal fibres, which are astral rays that connect with the intranuclear chromosomal fibres lying in the nuclear membrane; and astral rays. Each chromosome has a fibrillar connection with a centriole, half of the chromosomes being connected to one centriole and half to the other. These connections function in the poleward movement of the chromosomes.