FIG. 2. — Leiopelma hochstetteri; A, Whole testicular spermatozoon shown by light microscopy; B-Q, transmission electron microscopy; B, longitudinal section (ls) of the nuclear rostrum region of a spermatid, showing what appears to be the remnant of a short endonuclear canal; C, ls of the apical region of the acrosome vesicles; D, E, ls's of the anterior acrosome, showing condensed "rod-like" subacrosomal material; F, ls of the mid region of the acrosome; G, ls of the base of the nuclear rostrum. Note the distinct nuclear shoulders (ns), the axially located lacunae (l) and that the subacrosomal material extend beyond the base of the acrosomal vesicle (arrow); H-O, successive transverse sections (ts's) through the acrosomal region indicated; P, ts through nucleus; Q, ls through the base of the acrosome surrounding the nuclear rostrum. Note the lacunae containing putative perforatorial material (see also N). Abbreviations: av, acrosome vesicle; f, flagellum; h, head (acrosome and nucleus); l, lacunae; mp, midpiece; n, nucleus; nr, nuclear rostrum; ns, nuclear shoulders; sc, subacrosomal cone. Scale bars: A, 10 µm; B-Q, 1 µm.