Summary.1In the relatively unvarying climate of the northern New Hebrides (about 15oS. in the Pacific Ocean), most of the plants studied present seasonal reproductive phenomena.2There is a tendency for plants to flower and fruit from September to January or February and again in May and June.3The start of the longer flowering season coincides with the rise of temperature after the end of the cooler period of the year. The rainiest months of the year occur during this long flowering season.4Two of the plants studied–namely, the herbGeophila herbaceaand the shrubPiper meihysticum–reproduce throughout the year, and possibly the same applies to the treeFicus copiosa.5The natives rely upon the flowering and fruiting of certain wild trees to determine the time for planting certain crops (yams and sweet potatoes).6Of the cultivated perennial plants, the bread‐fruit and orange are seasonal, while the banana and papaw produce fruit throughout the year.7Seasonal phenomena in reproduction and leaf‐fall depend partly on an internal rhythm and partly on the environment, and in the interplay of these two controlling factors the one dominates in some species, the other in