Abstract
Four species of Gladiolus and one variety have been cytologically examined. The chromosome numbers of these species have been confirmed and of G. dracocephalus determined for the first time as 2n=80.
The behaviour of prochromosomes in G. tristis (2n=30) and G. primulinus (2n=60) has been fully examined. It is shown that the mitotic cycle in species with prochromosomes is essentially the same as in species with large chromosomes.
The nucleolus regularly persists to metaphase and sometimes until interphase. This is regarded as supporting the interpretation that the nucleolus, consisting of lipoids (fats), may partly act as a fuel substance.
The spindle appears to be compound in structure.
Cytomixis has been described in the genus for the first time.
The basic number is shown to be 10, not 15 as previously reported.
The causes and effects of vegetative reproduction in the genus are briefly discussed.