n = 9. Figs. 9, 10.
Hypnodendron arcuatum is the type and only species in section Lindbergiodendron. Prior to Touw's (1971) revision, most Australian specimens were named as H. arcuatum. The chromosome number reported for H. arcuatum (Ramsay, 1967) in fact refers to H. vitiense suhspecies australe (see Ramsay, 1974). There are therefore no previous records for this species.
In these studies, for the one population examined from the North Island, New Zealand (Table I, Appendix I), the chromosome number was determined as « = 9 (Fig. 9) at meiosis. The nine bivalents aligned in Fig. 10 consist of four large, four intermediate and one small one. These were quite comparable with other species having the same chromosome number in the section Hypnodendron, particularly those of H. vitiense subspecies australe.