Contributions to the anatomy of Freycinetia species from the Solomon Islands

Abstract

A preliminary investigation of six species of Freycinetia from the Solomon Islands indicates that the anatomy of this genus is relatively uniform, and differs only in degree rather than fundamental distinction from that of Pandanus. The complex elaboration of stomata found in some species of Pandanus is not seen in Freycinetia; in the latter genus the elaboration, if any, involves only a few simple outgrowths from cells bordering the stomata, or extensions of the cuticle, whereas in some species of Pandanus well-developed branched papillae occur. The vascular bundles of both leaves and stems are strongly sheathed by thickened cells and the phloem is in two distinctive strands. The ovules of species of Freycinetia may provide characters useful taxonomically; the presence or absence, and orientation, of raphide bundles in the long funicles and the presence or absence and character of the strophiole appear to vary from species to species. Current work involving more species of Freycinetia from a wider area, together with Sararanga, may throw further light on the possible use of anatomical features as diagnostic aids.